Busy. Please wait.

Forgot Password?

Don't have an account?  Sign up 

show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.

By signing up, I agree to StudyStack's Terms of Service and Privacy Policy.

Already a StudyStack user? Log In

Reset Password
Enter the email address associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know (0)
Know (0)
remaining cards (0)
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

FirstAid Microbio

First Aid Microbiology

What Structure gives rigid support and protects agains osmotic pressure Peptidoglycan
Peptidoglycan - composition Sugar backbone with cross-linked peptide side chains
Peptidoglycan - function Gives rigid support, protects against osmotic pressure
Cell wall/Cell membrane found in which type of bacteria? gram positive
Major surface antigen of gram positive bacteria Cell Wall/Cell membrane (Teichoic acid induces TNF and IL-1)
Teichoic acid is found in cell wall/cell membrane of gram positive bacteria - is major surface antigen, and induces TNF and IL-1
Outer membrane found in which type of bacteria? Gram negative
Major surface antigen of gram negative Outer membrane - contains the endotoxin (lipopolysaccharide). Lipid A induces TNF and IL-1
Composition of endotoxin Lipopolysaccharide
Site of oxidative and transport enzymes in bacteria Plasma membrane
Site of protein synthesis in bacteria Ribosome (50S and 30S)
Periplasm the space between the cytoplasmic membrane and outer membrane in gram-negative bacteria
Where are beta-lactamases in bacteria? In periplasm of gram negative bacteria
What bacterial structure protects agains phagocytosis? Capsule
What are bacterial capsules composed of? Polysaccharide (except for Bacillus anthracis, which contains D-glutamase)
The function of the pilus/fimbrai in bacteria mediates adherence of bacteria to cell surface. sex pilus forms attachment between 2 bacteria during conjugation.
Composition of bacterial pilus/fimbria Glycoprotein
Function of Flagellum in bacteria motility
Composition of bacterial flagellum protein
Significance of bacterial spores Provide resistance to dehydration, heat, and chemicals. Contain dipicolinic acid
What gives bacteria resistance to dehydration, heat, and chemicals the keratin-like coat, containing dipicolinic acid of SPORES
Contains a variety of genes for antibiotic resistance, enzymes, and toxins Bacterial Plasmid (made of DNA)
Glycocalyx - function mediates adherence to surfaces, especially foreign surfaces (eg: indwelling catheters)
Glycocalyx - composition polysaccharide
IgA proteases - function Allow some organisms to colonize mucosal surfaces (S.pneumo, N.meningitidis, N.gonorrhoeae, H.influenza)
Organisms that contain IgA proteases S. pneumo, N. meningitidis, N. gonorrhoeae, H. influenza
The only test that allows visualization of organisms in a sample from a patient: Direct Flourescant Antibody
Indirect Fluorescant Antibody Test Used to see if patient has antibodies agains a certain pathogen
Direct Fluorescant Antibody Test Used to directly see if an organism is present within a patient
Structures within bacterial cell walls that are common to both gram positive and gram negative bacteria Flagellum, Pilus, Capsule, Peptidoglycan, Cytoplasmic membrane
Structures in cell wall unique to gram positive organisms Teichoic acid, Cell wall
Structures in cell wall unique to gram negative organisms Endotoxin/LPS (outer membrane), Periplasm
Mnemonic to remember bugs that do not gram stain well These Rascals May Microscopically Lack Color (Treponema, Rickettsia, Mycobacteria, Mycoplasma, Legionella pneumophila, Chlamydia)
Stain for Treponema Is too thin to be visualized using traditional gram stain. Use darkfield microscopy and fluorescent antibody staining
Stain for Rickettsia Is an Intracellular parasite - so does NOT stain well.
Stain for Mycobacteria B/c wall has a high lipid content - it requires Acid-Fast stain
Stain for mycoplasma Does not have a cell wall so does NOT gram stain well
Stain for Legionell pneumophilia Is primarily intracellular so does NOT gram stain well. Need silver stain
Stain for Chlamydia Is an intracellular parasite so does NOT gram stain well. Also Lacks muramic acid in cell wall
Bacteria that lacks muramic acid in cell wall Chlamydia
During the Lag phase of bacterial growth curve There is metabolic activity without division
Phases of Bacterial growth curve Lag phase, Log phase, Stationary phase, Death phase
During the Log phase of the bacterial growth curve there is Rapid cell division
During the Stationary phase of the bacterial growth curve Nutrient depletion slows growth
During the Death phase of the bacterial growth curve Prolonged nutrient depletion and buildup of waste products lead to death
Exotoxins - source Certain species of some gram-positive and gram-negative bacteria
Endotoxins - source cell wall of most gram-negative bacteria
Are exotoxins secreted from cell? Endotoxins? Exotoxins = Yes. Endotoxins = No.
Chemical composition of exotoxins Polypeptides
Composition of endotoxins Lipopolysaccharide
Location of genes for exotoxins Plasmid or bacteriophage
Location of genes for endotoxins Bacterial chromosome
The toxicity of exotoxins is high or low? High (fatal dose is on the order of 1 mcg)
The toxicity of endotoxins is high or low? Low (compared to exotoxins) - fatal dose is on order of hundreds of mcg
General clinical effects of endotoxins Fever and shock
General mode of action of endotoxins TNF and IL-1
Antigenicity of exotoxins Induces high-titer antibodies called antitoxins
Antigenicity of endotoxins Poorly antigenic
What types of vaccines are used to protect agains exotoxins? Toxoids
What types of vaccines are used to protect against endotoxins? NO vaccine available! No toxoids formed
Heat stability of exotoxins Destroyed rapidly at 60C (except staphylococcal enterotoxin)
Heat stability of endotoxins Stable at 100C for 1 hour
Typical diseases caused by exotoxins Tetanus, Botulism, Diphtheria
Typical diseases caused by endotoxins Meningococcemia, sepsis by gram negative rods
Mnemonic to remember Bugs that secrete exotoxins Some Stinking Bugs Are Very Deadly Because They Secrete PolyPeptide Exotoxins (S.aureus, S.pyogenes, B.pertussis, Anthracis, Vibrio cholerae, Diphtheriae, Botulinum, Tetani, Shigella, Perfringens, Pseudomonas, E.coli)
Bugs that make superantigens S.aureus, and S.pyogenes
TSST-1 From S.aureus. Causes toxic shock syndrome. Causes fever, rash, and shock.
Enterotoxins S.aureus. Causes food poisoning.
Scarlet-fever erythrogenic toxin S.pyogenes. Is a Toxic-Shock-Like toxin (fever, rash, shock)
Bind directly to MHC II and T-cell receptor, activating large number of T cells to stimulate release of IFN-gamma, and IL-2. Superantigens (S.aureus, S.pyogenes)
AB Toxins - Are ADP ribosylating toxins that interfere with host cell function. B is binding component. A is active component which alters protein function. (Diptheria, Vibrio cholera, E.coli, Bordetella pertussis)
What does B component of AB toxin do? B = Binding. Binds to a receptor on the surface of host cell enabling endocytosis (ADP ribosylating toxins)
What does the A component of AB toxin do? A = Active. Component attaches an ADP-ribosyl to a host cell protein (ADP ribosylation) altering protein function.
ADP ribosylating Toxins - Organisms (5) Corynebacterium diphtheriae, Vibrio cholerae, E.coli, Pseudomonas, Bordetella pertussis
Toxins that inactivate EF-2 Corynebacterium diphtheriae, Pseudomonas (exotoxin A)
Inactivates elongation facto (EF-2) causing pharyngitis and "pseudomembrane" in throat Corynebacterium diphtheriae
ADP ribosylation of G protein stimulates adenylyl cyclase; increasing pumping of Cl- H20 into gut Vibrio cholerae
Mechanism of rice-water stools Vibrio cholerae: ADP ribosylation of G protein stimulates adenylyl cyclase increaseing the pumping of Cl- and H20 into the gut
Heat-labile vs. Heat-stabile toxin E.coli. Heat labile toxin stimulates Adenylate Cyclase. Heat-stable toxin stimulates guanylate cyclase. "Labile like the air, Stable like the ground."
Mechanism of Bordetella pertussis Stimulates adenylate cyclase; causes whooping cough; inhibits chemokine receptor causing lymphocytosis
Alpha Toxin Clostridium perfringens. Causes gas gangrene; gets double zone of hemolysis on blood agar
C. tetani inhibits? inhibitory neurotransmitter glycine. causes lockjaw
C.botulinum inhibits? Acetylcholine, causing anticholinergic symptoms and CNS paralysis
Floppy baby C. botulinum toxin. Found in canned food and honey.
Shiga toxin Produced by Shigella and also E.coli O157:H7. Cleaves host cell rRNA and enhances cytokine release causing HUS.
Streptolysin O A hemolysin made by S.pyogenes
ASO antibody Rheumatic fever (against streptolysin O)
Lipopolysaccharide found in cell wall of gram negative bacteria Endotoxins
Are endotoxins heat stabile or labile? Stabile
Endotoxins mode of Action Activate macrophages (IL-1, TNF, NO), Activate Complement (C3a, C5a), Activate Hageman factor (causing coagulation cascade which can lead to DIC)
Fermentation Patterns of Neisseria MeninGococci ferment Maltose and Glucose, Gonocci ferment Glucos
Pigment producing bacteria S.aureus (yellow), Pseudomonas aeruginosa (blue-green), Serratia marcescens (Red)
Gram +, Cocci, Clusters, Catalase +, Coagulase + S.aureus
Gram +, Cocci, Clusters, Catalase +, Coagulase -, Novobiocin Sensitive S.epidermidis (SEnsitive = S.Epidermis)
Gram +, Cocci, Clusters, Catalase +, Coagulase -, Novobiocin resistant S.saprophyticus (Resistant = Strong = Saphrophyticus)
Gram +, Cocci, Chains, Catalase -, Alpha (green) hemolysis, Capsule, Optochin sensitive, Bile soluble S.pneumoniae
Gram +, Cocci, Chains, Catalase -, Alpha (green) hemolysis, No capsule, Optochin resistant, Not bile soluble Viridans streptococci (S.mutans)
Alpha (green) hemolytic streptococci S. pneumoniae, or S. mutans (viridans)
How to tell between Alpha (green) hemolytic streptococci Capsule, +Quelling, Optochin sensitive, Bile soluble = S. pneumo. No capsule, Optochin resistant, not bile soluble = S.mutans
Gram +, Cocci, Chains, Catalase -, Beta (clear) hemolysis, Bacitracin sensitive Group A Strep (S.pyogenes)
Gram +, Cocci, Chains, Catalase -, Beta (clear) hemolysis, Bacitracin resistant Group B Strep (S.agalactiae)
How to tell between different Beta (clear) hemolytic streptococci Bacitracin sensitive = Group A Strep (S.pyogenes). Bacitracin resistant = Group B Strep (S.agalactiae)
Gram +, Cocci, Chains, Catalase -, Gamma (no) hemolysis Enterococcus (E.faecalis and Peptostreptococcus)
Gram -, Cocci, Maltose fermenter N.meningitidis
Gram -, Cocci, Maltose non-fermenter N.gonorrhoeae
Gram -, "Coccoid" rods H.influenza, Pasteurella, Brucella, Bordetella
Gram +, Bacilli, Spore Forming, ANerobic Clostridium (Tetani, Botulinum, Difficile, Perfringens)
How to distinguish between Clostridium species All are Catalse and Dismutase -. C.tetani = motile. C perfringens has two zones of hemolysis, and non-motile.
Gram +, Bacilli, Spore Forming, Aerobic Bacillus spp. (Anthracis, and Cereus)
Gram +, Bacilli, Non-spore forming, Anaerobic Actinomyces, Propionibacterium, Lactobacillus, and Bifidobacterium
Gram +, Bacilli, Non-spore forming, Aerobic Corynebacterium diptheriae, Listeria monocytogenes, Tropheryma whipplei, Erysipelothrix rhusiopathiae
Gram +, Cocci, Chains, Catalase -, Strict Anaerobe Peptostreptococcus
Gram -, Bacilli, Lactose fermenter, Fast fermenter Klebsiella, E.coli, Enterobacter
Gram -, Bacilli, Lactose fermenter, Slow fermenter Citrobacter, Serratia
Gram -, Bacilli, Lactos Non-fermenter, Oxidase - Shigella, Salmonella, Proteus
Gram -, Bacilli, Lactose non-fermenter, Oxidase + Pseudomonas
Chocolate agar with factors V (NAD) and X (hematin) H.influenza
Thayer-Martin media N.gonorrhoeae
Bordet-Gengou (potato) agar B. pertussis
Tellurite plate C.diphtheriae
Loffler's medium C.diptheriae
Blood agar C.diptheriae
Lowenstein-Jensen agar M.tuberculosis
Pink colonies on MacConkey's agar Lactose-fermenting enterics
CHarcoal yeast extract agar buffered with increased iron and cysteine Legionella
Sabouraud's agar Fungi
Congo red Amyloid; apple-green birefringence in polarized light (b/c of Beta-pleated sheets)
Giemsa stain Borrelia, Plasmodium, Trypanosomes, Chlamydia
PAS stain Stains glycogen, mucopolysaccharides. Is used to diagnose Whipple's disease
Ziehl-Neelsen Acid fast bacteria
India ink Cryptococcus neoformans
Silver stain Fungi, PCP, Legionella
Bacterial Genetics: Direct cell-to-cell transfer Conjugation
What type of DNA is transferred during conjugation Chromosomal or plasmid
Bacterial genetics: Phage-mediated cell to cell DNA transfer Transduction
Transduction Phage-mediated cell to cell DNA transfer
What type of DNA is transferred in Transduction Any gene in generalized transduction. Only certain genes in specialized transduction
Bacterial Genetics: Purified DNA taken up by a cell Transformation
Transformation is? When purified DNA is taken up by a cell. Can occur in prokaryotic or eukaryotic cells.
What type of DNA is transferred in Transformation Any DNA
Bacterial Genetics: DNA transfer to same or another chromosome or plasmid within a cell Transposition
Transposition is? DNA transfer to same or another chromosome or plasmid within a cell. Can occur in prokaryotes or eukaryotes
Nature of DNA transferred in Transposition DNA sequences "jumping genes"
What types of transfer procedure can eukaryotes undergo? Transformation or Transposition
What type of transfer procedure (bacterial genetics) can prokaryotes undergo? Conjugation, Transduction, Transformation, and Transposition.
Which bacteria have the genetic code for their toxin encoded in a lysogenic phage? Lysogeny: Botulinum toxin, Cholera toxin, Diphtheria toxin, Erythrogenic toxin of Strepcococcus pyogenes
Mnemonic to remember obligate aerobes Nagging Pests Must Breathe (Nocardia, Pseudomonas, Mycobacterium tb, Bacillus)
Which bacteria use an O2 dependent system to generate ATP? Obligate Aerobes (Nocardia, Pseudomonas, Mycobacterium TB, Bacillus)
What part of lungs is Mycobacterium TB found? Apices of the lung (b/c it is an obligate aerobe, and the apices of the lung have the highest PO2)
Obligate anerobe organisms Clostridium, Bacteriodes, Peptostreptococcus, Actinomyces
How do Obligate aerobes work? Use an O2-dependent system to generate ATP
Which organisms lack catalase and/or superoxide dismutase? Obligate anaerobes. The lack of catalase and/or superoxide dismutase makes them susceptible to oxidative damage
Characteristics of Obligate anaerobes Generally foul smelling (short-chain fatty acids), are difficult to culture, and produce gas in tissue (CO2, and H2O). Are generally normal flora in GI tract
Mnemonic to remember Obligate Intracellular bugs stay inside (cells) when it is Really Cold (Rickettsia, Chlamydia)
What is important about Obligate Intracellular bugs? They cannot make their own ATP (Rickettsia, Chlamydia)
Mnemonic to remember Facultative Intracellular bugs Some Nasty Bugs May Live FacultativeLY (Salmonella, Neisseria, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia)
Encapsulated Bacterial Organisms Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Klebsiella pneumonia. "Some Have Nice Kapsule"
Quelling reaction positive in bacteria who have capsules. Qwelling = Swelling
Bacterial capsule component Made of Polysaccharide.
Function of Bacterial Capsule An antiphagocytic virulence factor
What do Pneumovax, HiB, and Meningococcal vaccines have in common? All are encapsulated bacteria. Capsule serves as antigen in vaccines.
Who forms spores? Only certain gram-positive organisms form spores when nutrients are limited
Spore-forming organisms Aerobic: Bacillus anthracis, B.cereus. Anaerobic: Clostridium spp.
Do spores have metabolic activity? NO
Special component of spores Dipicolinic acid in core. Helps protect against destruction by heat and chemicals
How kill spores? Autoclave
Alpha-hemolytic bacteria 1. Streptococcus pneumoniae (catalase -, optochin sensitive) 2. Viridans streptococci (catalse -, optochin resistant)
Beta-hemolytic bacteria 1. Staphylococcus aureus (catalase/coagulase +) 2.Streptococcus pyogenes (catalase -, bacitracin sensitive) 3.Steptococcus agalactiae (catalase -, bacitracin resistant) 4.Listeria monocytogenes (tumbling motility, meningitis newborns, unpasteurized milk)
Only gram positive organism with endotoxin Listeria monocytogenes (found in soft cheese, deli meats, refrigerated). Tumbling motility
Function of catalase Degrades H202, an antimicrobial product of PMNs. H202 is a substrate for myeloperoxidase.
Protein A Staph aureus. Protein A is a virulence factor. It binds Fc-IgG, inhibiting complement fixation and phagocytosis
What type of immune response is elicited to TSST? TSST is a super antigen that binds MHC II and T-cell receptor, resulting in polyclonal T-cell activation. Will have a HIGH level of T cell cytokines.
Food poisoning from S.aureus Is due to ingestion of preformed enterotoxin. Is rapid-onset food poisoning.
Scalded skin syndrome Due to exfoliative toxin (s.aureus)
Acute bacterial endocarditis Staph aureus (IV drug user)
Streptococcus pyogenes causes: 1. PYOGENIC: pharyngitis, cellulitis, impetigo. 2. TOXIGENIC: scarlet fever, toxic shock syndrome. 3. IMMUNOLOGIC: rheumatic fever, acute glomerulonephritis.
Consequences of untreated Strep pyogenes PHaryngitis gives you rheumatic PHever and glomerulonePHritis
Jones Criteria for Rheumatic Fever No "RHEUM for SPECCulation" (Subcutaneous nodules, Polyarthritis, Erythema marginatum, Chorea, Carditis)
How increase host defenses against Step pyogenes? Antibody to M protein enhances host defenses against S.pyogenes
How detect recet S.pyogenes infection? ASO titer
Strep pneumo is the most common cause of? MOPS - Meningitis, Otitis Media, Pneumonia, Sinusitis
Sepsis in sickle cell anemia or post splenectomy Streptococcus pneumoniae
Rusty sputum pneumonia Streptococcus pneumonia
How does strep pneumo protect itself? It is encapsulated. Acts by inactivating complement to protect itself from opsonization.
What helps prevent bacteria from being immediately shed from mucosal surfaces? IgA protease. Found on Strep pneumo, H.influenza, N.meningitidis, N.gonorrhoeae
Group B streptococci Strep agalactiae (bacitracin resistant, Beta-hemolytic)
Pneumonia, meningitis, and sepsis in babies Streptococcus agalactiae
Enterococci Enterococcus faecalis, and E.faecium
Common cause of UTI and subacute endocarditis Enterococci (Enterococcus faecalis and E.faecium)
Lancefield grouping of enterococci is based on? C carbohydrate on the bacterial cell wall
Commonly affects prosthetic devices and catheters Staphylococcus epidermidis
Commonly contaminates blood cultures Staphylococcus epidermidis
How do biofilms form? By altering the surface tension of liquids (staph epidermidis)
Common cause of dental caries Strep mutans (viridans)
Common cause of subacte bacterial endocarditis Strep sanguis (viridans)
How remember optochin differentiation b/t alpha-hemolytic strep S.pneumon is optochin sensitive. Viridans strep "live in the mouth becase they are not afraid OF-THE-CHIN" (optochin resistant)
Clostridia categorization Gram-positive, spore-forming, obligate anaerobic bacilli that make exotoxins
Blocks glycine release from Renshaw cells in the spinal cord Tetanus toxin
Flaccid paralysis From Botulinum toxin blocking ACh release
Lecithinase Alpha-toxin of Clostridium perfringens
Cytotoxin An exotoxin that kills enterocytes. C.difficile. Commonly secondary to clindamycin or ampicillin use
ABCDEFG of Corynebacterium diptheriae ADP ribosylation, Beta-prophage, Corynebacterium, Diptheriae, Elongation Factor 2, Granules (metachromic)
Pseudomembranous pharyngitis Corynebacterium diphtheriae
Beta-prophage exotoxin Corynebacterium diptheriae. Exotoxin inhibits protein synthesis via ADP ribosylation of EF-2.
Looks like chinese letters on culture Corynebacterium diptheriae
The only bacterium with a protein capsule Bacillus anthracis
If come in contact with Anthrax Get Malignant pustule (painless ulcer); can progress to bacteremia and death
If inhale Anthrax Get flulike symptoms that rapidly progress to fever, pulmonary hemorrhage, and shock.
Wollsorter's disease Inhalation of Anthrax spores from contaminated wool
Black skin lesions Bacillus anthracis - vesicular papules covered by black eschar
Anthrax toxin 1) Lethal factor (releases TNF-beta, and IL-1). 2) Edema factor
Bacterial Rods forming long branching filaments resembling fungi Actinomyces and Nocardia
Gram + aerobe that causes oral/facial abscesses with "sulfur granules" that may drain through sinus tracts in skin Actinomyces
Gram-positive, weakly acid fast aerobe in soil causing pulmonary infection in ICH Nocardia asteroides
Txt for Nocardia vs. Txt for Actinomyces SNAP: Sulfa for Nocardia, Actinomyces use Penicillin
Facial abscesses draining through sinus tracts after bar brawl Actinomyces
Mycetoma in ICH Nocardia (mycetoma = brain and kidney abscesses)
Why are gram-negative bugs resistant to penicillin? Gram-negative outer membrane layer inhibits entry of penicillin G and vancomycin. Gram-negatives are susceptible to penicillin derivatives such as ampicillin
Lipooligosaccharide endotoxin N.meningitidis
N.gonorrhea vs. N.meningitidis GONOCOCCI (No polysaccharide capsule, No maltose fermentation, No vaccine). MENINGOCOCCI (Yes polysaccharide capsule, Yes maltose fermentation, Yes vaccine)
Causes gonorrhea, septic arthritis, neonatal conjunctivitis, PID N.gonorrhoeae
Causes meningococcemia and meningitis. Waterhouse-Friderichsen syndrome N.meningitidis
Mnemonic to remember clinical manifestations of Haemophilus influenza HaEMOP - Epiglottitis, Meningitis, Otitis media, and Pneumonia
Culture medium for H.influenza Chocolate agar with factors V (NAD) and X (hematin). Mnemonic: When a child has "flu," mom goes to five (V) and dime (X) store to buy some chocolate
Most invasive type of H.influnza Capsular type B (Vaccine contains type B capsular polysaccharide conjugated to diphtheria toxoid or other protein)
DOC of H.influenza meningitis Ceftriaxone. Use Rifampin prophylaxis in close contacts.
H.influenza vaccine Given between 2 and 18 months. Contains type B polysaccharide conjugated to diptheria toxoid or other protein
Mnemonic to remember the Enterobacteriaceae "Citizens Eat Kitkats Every Seventh daY. Some People May Prefer Salad." (Citrobacter, E.coli, Klebsiella, Enterobacter, Serratia, Yersinia, Shigella, Proteus, Morganella, Providencia, Salmonella)
Mnemonic to remember characteristics of Enterobacteriaceae "COFFEE" (Capsular, O antigen/Oxidase -, Flagellar antigen, Ferment glucose, Electron reducers of nitrate-nitrite, Enterobacteriaceae)
Somatic O antigen Polysaccharide of endotoxin, found in enterobacteriaceae
Virulence of Enterobacteriaceae the capsular K antigen is related to the virulence of the bug
Presents as pneumonia in alcoholics and diabetics. Red currant jelly sputum Klebsiella. Note it also is a common cause of nosocomia UTIs
The 3A's of Klebsiella Aspiration pneumonia, Abscess in lungs, Alcoholics
Pink colonies on MacConkey's agar Lactose-fermenting enteric bacteria
Mnemonic to remember which enterobacteriaceae ferment lactose "laCtose is KEE" (Klebsiella, E.coli, Enterobacter, and Citrobacter)
Salmonella vs. Shigella Both are non-lactose fermenters, both invade intestinal mucosa and cause dysentery. Salmonella is motile (Salmon swim) and has animal reservoir. Shigella is non motile and is transferred via Food, Fingers, Feces, and Flies. Shigella is much more virulent.
Symptoms of what bacterium can be prolonged with antibiotic txt Salmonella
What bacterium is commonly transmitted from pet feces (puppies), contaminated milk, or pork? Yersinia enterocolitica. (outbreaks are very common in day-care centers)
What bacterium can mimic Crohn's disease or appendicitis? Yersinia enterocolitica
Food poisoning from seafood Vibrio parahaemolyticus and Vibrio vulnificus
Food poisoning from reheated rice Bacillus cereus
Food poisoning from meats, mayonnaise, custard Staph aureus
Food poisoning from reheated meat dishes Clostridium perfringens
Food poising due to improperly canned foods (bulging cans) Clostridium botulinum
Food poisoning from undercooked meat (cheeseburger) E.coli 0157:H7
Food poisoning from poultry, meat, and eggs. Salmonella
What organisms cause bloody diarrhea? Campylobacter, Salmonella, Shigella, Enterohemorrhagic E.coli, Enteroinvasive E.coli, Yersinia enterocolitica, C.difficile, Entamoeba histolytica
Bloody diarrhea from a comma- or S-shaped organism growing at 42C and oxidase positive Campylobacter
Bloody diarrhea from gram -, motile, lactose negative bacteria Salmonella
Gram -, non-motile, lactose negative, low ID50 organism causing bloody diarrhea Shigella
Shiga-like toxin Enterohemorrhagic E.coli (bloody diarrhea)
Organism causing bloody diarrhea. Picked up at daycare. Presents as pseudoappendicitis Yersinia enterocolitica
Bloody diarrhea after clindamycin administration C.difficile (pseudomembranous colitis)
Causes of Watery Diarrhea Enterotoxigenic E.coli, Vibrio cholerae, C.perfringens, Protozoa (Giardia, Cryptosporidium), Viruses (Rota, Adeno, Norwalk)
Classic traveler's diarrhea Enterotoxigenic E.coli (no preformed toxin)
Rice-water diarrhea Vibrio cholerae (comma shaped organism)
cAMP inducing bacteria Vibrio cholera, Pertussis, E.coli, Bacillus antracis
Mechanism of Vibrio cholera toxin Is a cAMP inducer. It permanently activates Gs. "turns the 'on' on."
Mechanism of Pertussis toxin A cAMP inducer. Permanently disables Gi. "turns the 'off' off.
Mechanism of E.coli heat labile toxin A cAMP inducer. Ribosylates Gs protein to permanently activate AC thus increasing cAMP.
Mechanism of Bacillus anthracis toxin The edema factor is a cAMP inducer. Acts as a bacterial Adenylate cyclase increasing cAMP.
Culture for Legionella pneumophila Charcoal yeast extract culture with iron and cysteine. (Think of a French leegionnaire (soldier) with his silver helmet, sitting around a campfire (charcoal) with his iron dagger - he is no sissy (cysteine)
Stain for Legionella pneumophilia Silver stain. (Think of a French leegionnaire (soldier) with his silver helmet, sitting around a campfire (charcoal) with his iron dagger - he is no sissy (cysteine)
DOC for Legionnaires' disease Erythromycin
Transmission of Legionella Aerosol transmission from environmental water source habitat
Mnemonic to remember clinical manifestations of Pseudomonas PSEUDOmonas: Pneumonia (especially in CF), Sepsis (black lesions on skin), External otitis (swimmer's ear), UTI, Drug use and Diabetic Osteomyelitis. Also associated with wound and burn infections and hot tub folliculitis.
Aerobic gram-negative rod. Non-lactose fermenting. Oxidase + Pseudomonas aeruginosa
Pyocyanin A blue-green pigment produced by Pseudomonas aeruginosa.
Produces both an endotoxin and exotoxin A. Pseudomonas. Endotoxin (fever, shock). Exotoxin A (inactivates EF-2)
Txt of Pseudomonas aeruginosa Aminoglycoside plus extended-spectrum penicillin (eg: piperacillin and ticarcillin)
Common cause of gastritis and up to 90% of duodenal ulcers Helicobacter pylori
Urease positive organisms H.pylori and Proteus
Gram negative curved-rod with polar flagella. Urease positive H.pylori
Does H.pylori cause an acidic or alkaline environment? Alkaline
Txt of H.pylori Triple therapy: 1) bismuth, metronidazole, and either tetracycline or amoxicillin. or 2) (more expensive) metronidazole, omeprazole, and clarithromycin
Mnemonic to remember Zoonotic bacteria "Bad Bugs From Your Pet" (Borrelia burgdorferi, Brucella spp, Francisella tularensis, Yersinia pestis, Pasteurella multocida)
Undulant fever Brucella spp. "Unpasteurized dairy products give you Undulant fever"
Prarie dog vector Yersinia pestis (also caused by flea bites, or rodents)
Cellulitis post animal bite Pasteurella multocida
What could give one fever, chills, malaise, and an ulceroglandular (eschar) A rabbit bite. Francisella tularensis. Remember b/c St. Francis loved rabbits.
Infection as site of tongue piercing Fusobacterium spp
Positive whiff test Gardnerella vaginalis
Greenish vaginal discharge with fishy smell Gardnerella vaginalis
DOC for Gardnerella vaginalis Metronidazole
If suspect Pasteurella multocida, what do you do with the wound? Make sure to NOT suture.
A pleomorphic, gram-variable rod causing vaginosis Gardnerella vaginalis
Clue cells Gardnerella vaginalis
Positive PPD Current TB infection, Past exposure to TB, BCG vaccination
Negative PPD No TB infection, or immunocompromised (steroids, malnutrition, AIDS)
Primary TB localizes where Ghon complex focus usually in lower lobes. Also affects the hilar nodes
Possible results of Primary TB infection 1) Heals by fibrosis - have immunity and hypersensitivity. 2) Progressive lung disease - HIV and malnuorished pts. 3) Severe bacteremia - miliary tb. 4) Preallergic lymphatic or hematogenous dissemination - dorman tb bacilli in several organs - 2ndary TB
Secondary TB infection location Usually in apex of lung. Causes a fibrocaseous cavitary lesion. Caused by reinfection.
What are the signs of extrapulmonary TB? CNS (parenchymal tb or meningitis), VERTEBRAL BODY (Pott's dz). LYMPHADENITIS, RENAL, GI
What is a Ghon complex? Primary TB. Lobar and perihilar lymph node involvement
Types of Mycobacteria 1) Mycobacteria TB 2) Myocobacteria kansasii 3) M.scrofulaceum 4) M.avium-intracellulare 5) M.leprae 6) M.marinum
PPD is what type of hypersensitivity Type IV
Acid-fast organism causing disseminated disease in HIV Mycobacteria avium-intracellulare
Hot-tub lung Mycobacterium avium-intracellulare
Armadillo reservoir Mycobacterium leprae (Leprosy)
Classic TB sx Night sweats, weight loss, hemoptysis
Which type of Hansen's disease is worse? Two types of Leprosy: Lepromatous and Tuberculoid. Lepromatous is worse
Why is lepromatous leprosy worse than tuberculoid leprosy Lepromatous has failed cell-mediated immunity. Tuberculoid is self-limited
Chronic disease with hypopigmented skin and loss of sensation that prefers cooler areas of skin Hanson's dz (leprosy)
Txt for Leprosy Dapsone, Rifampin, Clofazamine
Toxicity of dapsone Hemolysis and methemoglobinemia
Leonine facies Lepromatous leprosy (LEpromatous = LEthal)
Gram -, obligate intracellular organisms that infect vascular endothelium Rickettsiae
Classic Triad of Rickettsiae Headache, fever, rash
Transmission of Rickettsiae All except Coxiella are transmitted by an arthropod vector and cause headache, fever, and rash. Coxiella is an atypical rickettsia because it is transmitted by aerosol and causes penumonia.
DOC for Rickettsial infections Tetracycline
Rat flea vector Endemic typhus (R.typhi)
Centrifugal rash (outward) Endemic typhus (R.typhi) - "TyPHus has centriPHugal rash"
Centripetal rash (inward) Rocky mountain spotted fever (R.rickettsii). "sPotted fever is centriPetal"
Human body louse Epidemic typhus (R.prowazekii)
Positive Weil-Felix Rickettsial diseases (except Q fever)
Rash on palms and soles migrating to wrists, ankles, and trunk. Headache and fever. Rocky Mountain spotted fever (R.rickettsii)
Palm and Sole Rash Rocky Mountain spotted fever, Syphilis, and Coxsackievirus A infection
Reaction that assays for antirickettsial antibodies which cross react with Proteus antigen Weil-Felix reaction (negative for Q fever)
Insidious onset of headache, non-productive cough, with X-ray showing diffuse interstitial infiltrate Mycoplasma pneumoniae
Eaton's agar Mycoplasma pneumoniae
Only bacterial membrane containing cholesterol Mycoplasma pneumoniae (no cell wall)
DOC for mycoplasma pneumoniae Tetracycline or erythromycin (bugs are penicillin resistant because they have to cell wall)
Small, non-motile, obligate intracellular (need ATP/NAD from host) bacteria/parasites that cause mucosal infections Chlamydiae
Two forms of Chlamydiae 1. Elementary body (small and dense) which Enters cell via Endocytosis. 2) Initial or Reticulate body, which Replicates in cell by fusion
Reactive arthritis, conjunctivitis, and nongonococcal urethritis Chlamydia trachomatis
Peptidoglycan wall that lacks muramic acid Chlamydia
Parrot fever Chlamydia psittaci
Atypical pneumonia with positive Giemsa Chlamydia pneumonia or C.psittaci
What type of hypersensitivity is caused by Chlamydia salpingitis? Type IV hypersensitivity (TH1 lymphocyte response)
Types A, B, C of Chlamydia trachomatis ABC = Africa/Blindness/Chronic infection (common cause of blindness in Africa)
Types D-K of Chlamydia trachomatis Urethritis/PID, ectopic pregnancy, neonatal pneumonia, or neonatal conjunctivitis. (remember that ABC causes African Blindess/Chronic infections, and L causes Lymphogranuloma venereum. D-K causes everything else)
Types L1, L2, and L3 of Chlamydia Trachomatis Lymphogranuloma venereum (L=L)
How txt neonatal chlamydial conjunctivitis Erythromycin eye drops
Positive Frei test Lymphogranuloma venereum (acute lymphadenitis) of Chlamydia trachomatic (type L)
Bacterial BLT Spirochetes (BLT = Borrelia, Leptospira, and Treponema)
Dark-field microscopy Treponema
Looks like ice-hooks on electron microscopy Leptospira interrogans (a spirochete)
Rat-bite fever Streptobacillus monilliformis (erythematous rash with discrete 1-4mm macules on extremities (including palms, soles and face)
bull's eye rash Borrelia burgdoferi (Lyme dz)
3 stages of Lyme dz 1) Erythema chronicum migrans, flulike sx. 2) Neurologic and cardia manifestations. 3) autoimmune migratory polyarthritis
Erythema chronicum migrans Lyme disease
Mnemonic for manifestations of Lyme dz BAKE a key Lyme pie: Bell's palsy, Arthritis, Kardiac block, Erythema chronicum migrans
DOC for lyme disease Tetracycline, Doxycycline, or penicillins
Painless bumps on arm of tropical population Yaws = Treponema pertenue
Primary syphilis Presents with painless chancre
Secondary syphilis Disseminated disease with constituitional symptoms, maculopapular rash (palms and soles), condylomata lata
Tertiary syphilis Gummas, aortitis, neurosyphilis (tabes dorsalis), Argyll Robertson pupil
Broad based ataxia, positive Romberg, Charcot joints, stroke w/o hypertension Neurosyphilis (tabes dorsalis)
Saber shins, saddle nose, deafness Congenital syphilis
FTA-ABS vs. VDRL FTA-ABS: more specific, earliest positive, remains positive the longest. VDRL: cheapest, titer will fall late in disease
Nonspecific antibody that reacts with beef cardiolipin VDRL
Mnemonic to remember false positives of VDRL VDRL: Viruses (mono, hepatitis), Drugs, Rheumatic fever and rheumatic arthritis, Lupus and leprosy
Eukaryotes with cell wall Fungi
Budding yeast with pseudohyphae in culture at 20C; germ tube formation at 37C Candida albicans
DOC for Candida albicans Nystatin for superficial infections. Amphotericin B for serious systemic infection
Systemic mycoses from Southwestern United States, California Coccidioidomycosis
Only systemic myocosis w/no yeast form Coccidiodes immitis (forms mold and spherules
Rounded spherules filled with endospores Coccidiodes immitis
Found in sand of arid environment. Dust storms Coccidiodes immitis
Systemic mycosis found in Mississippi and Ohio river valleys Histoplasmosis
Systemic mycosis found east of Mississippi River and Central America Blastomycoses
Systemic mycosis transmitted by bird or bat droppings Histoplasmosis
Tiny yeast inside macrophages. "Captain's wheel" appearance Histoplasmosis
Broad-based, budding yeast Blastomycosis
Characterizations of dimorphic fungi Mold in soil at lower temperatures. Yeast in tissue at higher temperatures (except coccidiomycosis which is a spherule in tissue)
DOC for Systemic mycoses Local infection: Ketoconazole or Fluconazole. Systemic: Amphotericin B
Sabouraud's agar Fungi
Cutaneous mycoses Tinea versicolor, Tinea nigra, Tinea pedis/cruris/corporis/capitis.
Hypopigmented skin lesions in hot, humid weather Malassezia furfur (tinea versicolor)
DOC for Tinea versicolor (Malassezia furfur) Topical miconazole, selenium sulfide
Brownish spot infecting keratinized layer of skin Cladosporium werneckii (Tinea nigra)
DOC for Tinea nigra (Cladosporium werneckii) Salicylic acid
Dermatophytes Microsporum, Trichophyton, and Epidermophyton
Epidermophyton Infects skin and nails
Microsporum Infects hair and skin
Trichophyton Infects hair, skin, and nails
Mnemonic to remember types of Ringworm "3C's at the PUB" (Cruris, Corporis, Capitis, Pedis, Unguium, Barbae)
Characteristics of Ringworm Itchy, red, raised, scaly patches that may blister and ooze. Patches have sharply defined edges. Are often redder around the outside with normal skin tone in the center creating the appearance of a ring.
How diagnose Ringworm KOH, Sabouraud's agar, Wood's lamp
Germ tubes at 37C Candida
45 degree angle branching septate hyphae Aspergillus
Rare fruiting bodies Aspergillus
5-10 um yeasts with wide capsular halo Cryptococcus
Narrow-based unequal budding Crytococcus
Irregular broad (empty-looking) nonseptate hyphae, wide-angle branching Mucor
Opportunistic fungal infections Candida albicans, Aspergillus funigatus, Cryptococcus neoformans, Mucor and Rhizopus
Mold with irregular nonseptate hyphae branching at wide angles (>90) Mucor and Rhizopus
Frontal lobe abscess in ketoacidotic diabetic Mucormycosis
Causes pneumonia in ICH due to over-replication of type II pneumocytes and over-production of surfactant Pneumocystis carinii
Diffuse interstitial pneumonia in AIDS patients PCP
Is PCP a protozoa or yeast? Yeast
Cysts and intracystic bodies on methenamine silver stain of lung tissue PCP
DOC of PCP TMP-SMX, Pentamidine, Dapsone
When start prophylaxis for PCP in AIDS pt? When CD4 drops <200 cells/mL
Manifestations of Aspergillus infection 1) Allergic bronchopulmonary mucus plugs 2) Fungus balls (aspergilloma) 3) Invasive Aspergillosis
Urease positive, pigment production on niger seed agar Cryptococcus neoformans
Latex agglutination test detects polysaccharide capsular antigen Cryptococcus neoformans.
A heavily encapsulated, non-dimorphic yeast found in soil and pigeon droppings Cryptococcus neoformans
India Ink Cryptococcus neoformans
Subcutaneous fungal infections Sporothrix schenckii and Pseudallescheria boydii
Dimorphic fungus that lives on vegetation and is traumatically introduced into skin, typically by a thorn Sporothrix schenckii (rose gardener's disease)
Local pustule or ulcer with nodules along draining lymphatics (ascending lymphangitis) Sporothrix schenckii
Cigar-shapped budding yeast Sporothrix schenckii
DOC for Sporothrix schenckii Itraconazole or Potassium iodide
Clinical manifestations of Entamoeba histolytica Amebiasis: bloody diarrhea (dysentery), liver abscess, RUQ pain
DOC for Entamoeba Histolytica Metronidazole and Iodoquinol
How is entamoeba histolytica transmitted Fecal-oral (or anal-oral sexual contact). Cysts in water
How do you diagnose Entamoeba histolytica Serology and/or trophozoites or cysts in stool
Bloating, flatulence, and foul-smelling diarrhea after a camping/hiking trip Giardia lamblia
How is Giardia lamblia transitted? Cysts in water
How do you diagnose Giardia lamblia? Look for the Trophozoites or cysts in the stool
What will a colonic biopsy of a patient with Entamoeba histolytica show? Ulcers in the colon w/o inflammatory response. Flask-like ulcers in the submucosa.
DOC in Giardia lamblia Metronidazole
Severe diarrhea in AIDS pts. Mild watery diarrhea in non-HIV pts. Cryptosporidium
How do you diagnose Cryptosporidium Cysts on acid-fast stain
How is Cryptosporidium transmitted? Cysts in water (fecal oral)
Presents with prolonged realapsing watery diarrhea, abdominal cramps, and fever after eating rasberries Cyclospora cayetanensis
Commonly contaminates berries (rasberries, and strawberries) Cyclospora cayetanensis
How do you diagnose Cyclospora cayetanensis Acid fast cysts in stool (not as acid fast as Cryptosporidium parvum). Also it causes UV epifluorescence.
How txt Cryptosporidium? No txt
Commonly causes brain abscesses in HIV patients Toxoplasma (ring enhancing brain lesions)
How is toxoplasma transmitted? Oocysts in cat feces, or tissue cysts in undercooked meat. Also transplacentally
What is DOC for toxoplasma TMP-SMX
What is the vector for malaria? the Anopheles mosquito
What are the types of Malaria? Plasmodium Vivax, P.ovale, P.malariae, P.falciparum
Classic presentation of malaria Cyclic fever, headache, anemia, splenomegaly
Which type of malaria can cause severe cerebral infection? Plasmodium falciparum
How is relapse of malaria prevented? Primaquine (relapse occurs in P.vivax, and P.ovale)
What is recrudescence? Relapse of malaria, but not from liver. Seen in P.falciparum
Which type of malaria requires Duffy factor? P.vivax
Which type of malari infects reticulocytes? P.vivax and P.ovale. Falciparum infects RBCs in all stages of maturation. Malariae infects only mature RBCs
Which type of malaria infects mature RBCs? P.malariae
Which type of malaria infects RBCs in all stages of maturation? P.falciparum
In malaria life cycle: Mosquitos inject what type of cells into blood? Sporozoites
Hypnozoites are present in which types of malaria? P.vivax, P.ovale
Which type of malaria cells are released from the liver? Merozoites
Schizonts are present in what part of the malaria life cycle? Schizonts are part of the erythrocyte cycle. Merozoites are released from liver into blood. Schizonts are in RBCs - cause RBC rupture releasing gametocytes which are taken up by another mosquito.
Gametocytes of malaria are matured and fertilized into sporozoites where? Maturation and fertilization occur in the mosquito. Released sporozoites migrate to the salivary gland of the mosquito.
Foul-smelling, greenish vaginal discharge, causing itching and burning Trichomonas vaginalis.
How diagnose Trichomonas vaginalis? Trophozoites (motile) on wet mount. Vaginal discharge pH > 4.5
Risks of Trichomonas vaginalis Increases risk of preterm birth and HIV infection
"Strawberry cervix" Trichomonas vaginalis.
How txt Trichomonas vaginalis? Metronidazole
Vector is the Reduviid bug (kissing bug) Trpanosoma cruzi (Chagas' disease)
Characteristics of Chagas' disease Dilated cardiomyopathy, megacolon, megaesophagus
Romano's sign Periorbital edema in Chagas' disease
How diagnose Chagas' disease? Trypomastigotes in smooth muscle, GI tract, and blood smear
How does Trypansoma cruzi avoid immunity? Antigenic variation (VSG - variant surface glycoprotein) surface Ag
Tsete fly Vector of Trypanosoma gambiense and T.rhodesiense (African Sleeping Sickness)
DOC in Trypanosoma cruzi Nifurtimox
Winterbottom's sign Posterior cervical adenopathy in Afrcan Sleeping Sickness
DOC in treating Typanosoma gambiense or T.rhodesiense Suramin for blood born disease or Melarsopro for CNS penetration
Sandfly Vector for Leishmania donovani (Visceral leishmaniasis or kala-azar)
Where do the promastigotes of Leishmaniasis reproduce? Macrophages (this is how diagnose - look for amastigotes in the macrophages)
Kala-azar Visceral Leishmaniasis: fever, pancytopenia, hepatosplenomegaly
How diagnoses Leishmaniasis Look for macrophages containing amastigotes
What is DOC for Leishmaniasis? Sodium stibogluconate
Iodes nymph vector for Lyme disease and Babesia microti
Babesiosis Fever and anemia
Maltese cross of blood smear Babesiosis
How txt Babesia? Quinine, clindamycin
Rapidly fatal meningoencephalitis common acquired through the cribriform plate when diving into a freshwater lake Naegleria
How diagnose Naegleria? Amebas in spinal fluid
Sudden onset of sever fatal Praimary Amebic Meningoencephalitis (PAM) Naegleria fowleri
How txt Naegleria fowleri? No txt
Cestodes Tapeworms (have long flattened body, proglottid body segments (self-contained hermaphroditic reporduction units), no gut
Species of tapeworms (cestodes) Taenia saginata, Diphyllobothrium latum, Taenia solium, Echinococcus granulosus
Undercooked pork tapeworm; larvae cause mass lesion in the brain, cysticercosis Taenia solium
Calcified cysticerci on CT or MRI Taenia solium
Beef tapeworm Taenia saginata
Txt of choice for Taenia solium Praziquantel/niclosamide. Albendazole for cysticercosis
Hydatid cysts "Cysts w/in cysts" - common in Echinococcus granulosus
Cystic rupture causing anaphylaxis Echinococcus granulosus
Shepard with multiple cysts Echinococcus granulosis
Dog/sheep life cycle. Echinococcus granulosis
Treatment of choice for Echinococcus granulosus Albendazole
In treating echinococcus granulosus cysts, is aspiration a good method? Aspiration contraindicated because of risk of cystic rupture
Trematodes Flukes. Have a blind alimentary canal, and dorsal and ventral suckers
Species of Trematodes (Flukes) Schistosoma, Clonorchis sinensis
Diphyllobothrium latum Fish tapeworm
Helminth cause of Vit B12 deficiency Diphyllobothrium latum (b/c fish tapeworm eats it in jejunum)
Host of schistosoma spp Snails in water
How is schistosoma transmitted Through skin of humans
Intense pruritic rash at entry site followed by granulomas, fibrosis, and inflammation of the liver and spleen Schistosoma spp
Common cause of bladder cancer in Japan Schistosoma spp
DOC for Schistosoma Praziquantel
Chinese liver fluke Clonorchis sinensis
Cholangitis leading to cholangiocarcinoma Clonorchis sinensis
Transmission of clonorchis sinensis Eating undercooked fish
DOC in Clonorchis sinensis Praziquantel
Transmitted by undercooked crab meat Paragonimus wetermani (Lung fluke)
Lung Fluke Paragonimus westermani
Trematode mimicking TB Paragonimus westermani (lung mass - leading to 2ndary bacterial infection)
Treatment of choice for Paragonismus westermani Praziquantel
Nematodes Roundworms (wormlike, tubular alimentary tracts)
Hookworm Necator americanus and Ancylostoma duodenale
Ancylostoma duodenale Hookworm
Transmission of Ancylostoma duodenale Commonly known as Hookworm. Larvae penetrate skin of feet.
Clinical manifestations of Ancylostoma duodenale Commonly known as hookworm. Intestinal infections can cause anemia (in intestine)
DOC in Ancylostoma duodenale Mebendazole/pyrantel pamoate
Giant Nematode (roundworm) Ascaris lumbricoides
Most common helminth in the world Ascaris lumbricoides
Nematode presenting with distended abdomen, or intestinal obstruction Ascaris lumbricoides
DOC in Ascaris lumbricoides Mebendazole/pyrantel pamoate
Pinworm Enterobius Vermicularis
Enterobius vermicularis Pinworm
Nocturnal pruritic ani/vulvae Pinworm (Enterobius vermicularis)
DOC in Enterobius vermicularis Mebendazole/pyrantel pamoate
What is only Nematode that has larvae present in feces? Strongyloides stercoralis (allows for autoinfection)
How are Strongyloides stercoralis transmitted Larvae in soil penetrate the skin
Clinical manifestations of Strongyloides stercoralis Cause intestinal infection. Red, raised, serpiginous lesions on buttock and lower back. Can cause hyperinfection (entercolitis, and widespread dissemination)
DOC in treating Strongyloides stercoralis Ivermectin/thiabendazole
Helminth infection resulting in periorbital edema, muscle pain and weakness Trichinella spiralis
DOC in Trichinella spiralis Thiabendazole
How diagnose Trichinella spiralis? Muscle biopsy
Roundworm (nematode) found in drinking water causing skin inflammation and ulceration Dracunculus medinensis
DOC in Dracunculus medinensis Niridazole
Deer (crysops) fly Vector for Loa Loa
Also known as Eye worm (b/c can see worm crawling in conjunctiva) Loa loa
DOC in Loa loa Diethylcarbamazine
Female blackfly Vector of Onchocerca volvulus (African River blindness)
River Blindness Onchocerca volvulus
DOC in Onchocerca volvulus Ivermectin (I=Eye)
Night-biting female mosquito Wuchereria bancrofti (Elephantiasis)
Elephatiasis Wuchereria bancrofti
Causes blockage of lymphatic vessels resulting in lymph node scarring Wucheria bancrofti (Elephantiasis)
Causes rectal prolapse Trichuris trichiura (Whipworm)
Visceral larva migrans Toxocara canis (eggs passed in dog feces)
Ocular larva migrans Toxocara canis (granulomas - if in retina = blindness)
DOC in Toxocara canis Diethylcarbamazine
DOC in Wuchereria bancrofti Diethylcarbamazine
Parasite Hints: Brain cysts, seizures Taenia solium (cysticercosis)
Parasite Hints: Liver cysts Echinococcus granulosus
Parasite Hints: B12 deficiency Diphyllobothrium latum
Parasite Hints: Biliary tract disease Clonorchis sinesis
Parasite Hints: Hemoptysis Paragonismus westermani
Parasite Hints: Portal hypertension Schistosoma mansoni
Parasite Hints: Hematuria, bladder cancer Schistosoma haematobium
Parasite Hints: Microcytic anemia Ancylostoma, Necator
Parasite Hints: Perianal pruritis Enterobius
Only single-stranded DNA virus Parvoviridae (Parvovirus B19)
All DNA viruses are linear except: Papovavirus (HPV, JC, BK), and Hepadnaviruses (HepB) - both are circular
Only RNA virus that is double-stranded Reoviridae (Rotavirus). "Repeatovirus = Reovirus"
Naked (non-enveloped) DNA viruses "PAP" (as in you have to be naked for a PAP smear): Parvoviridae (remember ssDNA), Adenovridae, and Papovaoviridae (BK, JC, HPV)
Enveloped DNA viruses HPH: Hepadnaviridae (HepB), Poxviridae, and Herpesviridae
Naked viral genome infectivity: Infectious naked viruses Nake nucleic acids of most dsDNA (except Poxviruses and HBV) and (+) sense ssRNA viruses are infectious
Naked viral genome infectivity: Non infectious naked viruses Naked nucleic acids of (-) strand ssRNA and dsRNA viruses are not infectious
How do viruses acquire their envelope? Generally, enveloped viruses acquire their envelopes from plasma membrane when they exit from cell. Exceptions are herpesviruses, which acquire envelopes from nuclear membrane
Virus ploidy: All viruses are: Haploid (1 copy of DNA or RNA). Exception are retroviruses which have 2 identical ssRNA molecules (diploid)
Only diploid virus Retroviruses (HIV) - have 2 identical ssRNA molecules
All DNA viruses replicate where? In the nucleus (except poxvirus - replicates in cytoplasm)
All RNA viruse replicate where? In the cytoplasm (except influenza virus and retroviruses (nucleus)
Mnemonic to remember DNA viruses HHAPPPy viruses: Hepadna, Herpes, Adeno, Pox, Parvo, Papova
All DNA viruses are icosahedral except: Pox viridae (complex - brick shaped). "Pox in a Box"
All DNA viruses replicated in the nucleus except: Pox viridae (carries its own DNA-dependent RNA polymerase)
Categorization of Hepadnavirus Enveloped, dsDNA, partial circular
Medical importance of Hepadnavirus Hepatitis B: can be acute or chronic hepatitis, there is a vaccine available, is not a retrovirus but does have a reverse transcriptase.
Categorization of Herpesviruses dsDNA, linear, enveloped (note: only enveloped viruse to acquire envelope from nuclear membrane - remember, most get from plasma membrane)
Types of Herpesviruses HSV1 (oral lesions, keratoconjunctivitis), HSV2 (genital lesions), VZV (chickenpox, zoster, shingles), EBV (mono, burkitt), CMV (ICH, congenital dfts), HHV6 (roseola - exanthem subitum), HHV8 (kaposi's sarcoma)
Which type of Herpesvirus generally presents with oral lesions? HHV-1 usually is the culprit of cold-sores. HSV1 can sometimes also cause genital lesions. HSV2 generally presents as genital lesions (with some oral lesions)
Which Herpesvirus presents with genital lesions? HSV2 (sometimes also causes oral lesions). HSV1 is usally oral (and some genital) lesions
A herpetic lesion on nurses finger Herpetic whitlow (from physical exam of person's mouth with herpes)
What is most common type of congenital herpes? HSV2 (75%)
Categorization of Adenovirus dsDNA virus, linear, naked (part of PAP - other nakeds are Parvo and Papova)
Common clinical manifestations of Adenovirus Febrile pharyngitis (sore throat), Pneumonia, Conjunctivitis - "pink eye"
What causes "pink eye"? Adenovirus
Categorization of Parvovirus ssDNA (the only one!), linear, negative sense, naked
Why does a physician have to closely monitor a fetus of a mom exposed to Parvovirus B19? Can cause hydrops fetalis!
Can cause an aplastic crises in patients with sickle cell disease Parvovirus B19
"Slapped cheek" Parvovirus B19
Parvovirus B19 is aka? Erythema infectiosum (fifth disease)
Categorization of Papovavirus dsDNA, circular, naked
Types of Papovavirus HPV, JC, BK
Which types of HPV can lead to cancer? HPV 16, 18, 31, 45 can predispose to cervical, penile, and anal cancer
How is HPV transmitted? Direct contact (sexual and non-sexual, minor trauma, and maternal-fetal
Condyloma acuminata from? HPV 6-11. most common viral STD.
What regulatory genes does HPV inactivate? Rb, and p53
Progressive multifocal leukoencephalopathy is caused by? JC virus (a Papovavirus). Presents as demyelination of CNS, hemiparesis, cognitive problems, visual field defects.
How does PML present? Demyelination of CNS, hemiparesis, cognitive problems, and visual field defects in ICH. Is a subcortical lesion that doesn't enhance with contrast on MRI
How does BK virus present Asymptomatic in immunocompetent hosts. In ICH can have hemorrhagic cystitis, and renal transplant rejection
What is the smallest DNA virus? Parvovirus (also is ssDNA!)
What is the largest DNA virus? Poxvirus
Categorization of Poxvirus dsDNA, linear, brick-shaped, enveloped
Types of Poxvirus Smallpox, Vaccinia, Molluscum contagiosum
What is the only DNA virus that replicated in the cytoplasm? Poxvirus
How tell between smallpox and chicken pox? SMALLPOX: prodrome fever 2-4 day b/f rash, all pocks at same stage, pocks are deep seated, firm pustules, lesions on face, palms, and soles. CHICKENPOX: no prodrome, pocks at different stages, "dew drops on rose petal", mostly on trunk (few palms/soles)
Molluscum Contagiosum A pox viruse. Have umbilicated skin lesions with eosinophilic cytoplasmic inclusion bodies
Positive vs. Negative Sense Positive sense RNA produces a negative sense intermeidate to produce a genomic duplictate. Negative sense RNA produces a positive sense intermediate to produce a genomic duplicate
Categorization of Picornaviruses non-enveloped, ssRNA, positive sense, linear, icosahedral
Which RNA viruses are naked? Reoviruses, Picornaviruses, Calciviruses, Herpeviridae. "Rachel Plays Her Clarinet naked"
What is the only double-stranded RNA virus Reovirus - of which Rotavirus is most famous
Salk/Sabin vaccines for Polio virus (a Picornavirus)
Echovirus can cause? Aseptic meningitis
Types of Picornaviruses Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, Hepatitis A virus (PERCH)
Most common cause of the common cold Rhinovirus (a Picronavirus - ssRNA, +, linear, icosahedral)
Coxsackie A16 Hand, foot, and mouth disease
Coxsackie B myocarditis
Common cause of summer meningitis Coxsackie virus (aseptic)
Sudden onset of RUQ pain, fever, dark urine, and light stool after an international trip Hepatitis A (picornaviridae, ssRNA non-enveloped)
Causes of Chronic Hepatitis HBV, HCV, HDV
Categorization of Calciviruses Non-enveloped, ssRNA, +, linear, Icosahedral
Star of David appearance on EM Norwalk virus (a Calcivirus) - common cause of gastroenteritis
Outbreak on cruise ship Norwalk viruse (a Calcivirus - ssRNA, naked) - found on any type of food (common on shellfish). very infectious
Categorization of Reovirus Non-enveloped, dsRNA, linear segmented, double icosahedral (only dsRNA virus!)
Colorado Tick Fever A Reovirus (dsRNA), presents similar to Rocky Mountain spotted fever
#1 cause of fatal diarrhea in children Rotavirus (a Reovirus - dsDNA).
How diagnose Rotavirus? Look for VP6 antigen in stool. Also know that is dsRNA
How remember enveloped, ssRNA, + sense viruses? "Cons Rob From Tourists" (Coronaviruses, Retroviruses, Flaviviruses, Togaviruses)
Categorization of Flaviviruses Enveloped, ssRNA, + sense, linear
Types of Flaviviruses HCV, Yellow fever, Dengue fever, St. Louis encephalitis, West Nile Virus
Fever with jaundice Yellow fever (flavivirus). Transmitted by aedis aegypti mosquito
Break bone fever Dengue fever (a flavivirus)
Dengue virus has tropism for which type of cells? Striated muscle - causing break bone fever
Culex mosquito/Birds in life cycle St. Louis encephalitis, and West Nile virus
Older individual bitten by a mosquito causing encephalitis West Nile virus
Categorization of Togaviruses Enveloped, ssRNA, positive sense, linear (part of 'Cons Rob From Tourists')
Types of Togavirus Rubella (German measles), Eastern equine encephalitis, Western equine encephalitis
What is the only Togavirus that is not transmitted via arthropod? Rubella (German measles)
Which is more severe WEE or EEE? EEE is more severe (mortality approx 30% in those who develop encephalitis). Both are Togaviruses
Congenital Rubella Purpura (blueberry muffin rash), Deafness, Cataracts, Heart defects (PDA), Retardation, Retinopathy
Latino pregnant women comes in with 3 day rash that began at her face and descended. What do you worry about? Rubella (German measles) - can cause congenital rubella!!!
Categorization of Retroviruses Enveloped, ssRNA, positive sense, linear. Have reverse transcriptase (HIV)
Categorization of Coronaviruses Enveloped, ssRNA, positive sense, linear. Have Helical capsid (all others in this group of Cons Rob From Tourists are Icosahedral)
Types of Coronaviruses SARS and Common cold
SARS Triphasic course. 1) Fever, myalgia 2) Cough, dyspnea 3) Recurrent fever, progressive infiltrates
How to remember the Enveloped, ssRNA, negative sense viruses Real Foes Are Better Paralyzed Or Dead (Rhabdoviruses, Filoviruses, Arenaviruses, Bunyaviruses, Paramyxoviruses, Orthomyxoviruses, Deltavirus)
Categorization of Orthomyxoviruses Enveloped, ssRNA, negative sense
Only clinically important Orthomyxoviruses Influenza virus
Influenza virus An orthomyxovirus (ssRNA, -, enveloped)
What are the major antigens of the influenza virus? H and N
How does influnza virus evade the immune system? 1) Antigenic drift (gradual alteration of H and/or N w/in subtype which occurs in both A and B viruses). 2) Antigenic shift (appearance in human population of new subtype of A virus from animal reservoir like swine)
Antigenic drift Gradual alteration (point mutations) of H and/or N w/in subtype which occurs in both A and B viruses
Antigenic shift Appearance in human population of new subtype of A virus (from animal reservoir like swine)
Categorization of Parmyxoviruses Enveloped, ssRNA, negative sense, linear.
Types of Paramyxoviruses PaRaMyxovirus: Parainfluenza, RSV, Measles, Mumps
Parainfluenza virus A Paramyxovirus (ssRNA, enveloped, negative sense). Commonly causes croup (PIV1). PIV3 is second leading cause of bronchiolitis and pneumonia in infancy. PIV4 is asymptomatic or mild cold.
Croup Parainfluenza virus 1 (a Paramyxovirus). Presents with a barking cough, and respiratory stridor
How does Parainfluenza virus type 3 present? Second leading cause of bronchiolitis and pneumonia in infancy
Bronchiolitis in babies RSV
DOC for RSV Ribavirin
Which Paramyxovirus carries an RNA dependent RNA polymerase? RSV
Antigeninc derterminants of RSV F (fusion), G (attachment)
Measles A Paramyxovirus (ssRNA, enveloped, negative sense, linear). Aka: Rubeola. 3C's: Cough, Coryza, Conjunctivitis. Also Koplick spots. Maculopapular rash which starts head, and spreads downward
Cough, Coryza, Conjunctivitis Measles
Rash that spreads like a paintcan poured on someone Measles
Slowly progressive central nervous system disease with mental deterioration and incoordination many years after measles SSPE (Subacute Sclerosing Panencephalitis)
Parotid gland swelling Mumps
Orchitis Mumps
Categorization of Rhabdoviruses Enveloped, ssRNA, negative sense, linear. Only one is Rabies
Rabies Rhabdovirus (ssRNA, enveloped, negative sense)
Negri bodies Rabies
Bullet-shaped, linear genome Rabies (ssRNA, negative sense, Rhabdovirus)
Virus begins in striated muscle, ascends neurons to CNS where it spreads peripherally from CNS along neurons Rabies
Concentrates in salivary glands Rabies
How does Rabies present? 1) FURIOUS: hydrophobia, hallucinations, agitation, biting. 2) DUMB: ascending flaccid paralysis
What is mortality of Rabies? 100% (if not treated)
How treat Rabies? Rabies immunoglobulin and vaccine within 48-72 hours
Categorization of Filoviruses Enveloped, ssRNA, negative sense, linear. (part of Real Foes Are Better Paralyzed Or Dead)
Types of Filoviruses Ebola virus, Marburg virus
Hemorrhagic fevers resulting in DIC and Death Ebola and Marburg virus (Filoviruses)
Categorization of Arenaviruses Enveloped, ssRNA, negative sense, circular.
Types of Arenaviruses LCV (lymphocytic choriomeningitis), Lassa Virus
Lymphocytic Choriomeningitis Virus Arenavirus. Has "sand" granuels due to ribosomes. Causes meningitis from aerosolization of murine feces/urine.
Lassa Virus Arenavirus. Has "sand" granuels due to ribosomes. Classic presentation is bleeding, neck/face swelling, and shock
How is Lassa virus transmitted Rodent to human or human to human.
Meningitis spread by mice LCV (Arena virus)
Categorization of Bunyaviruses Enveloped, ssRNA, negative sense, circular.
Types of Bunyaviruses California encephalitis, Sandfly/Rift Valley Fevers, Crimean-Congo hemorrhagic fever, Hantavirus
Pulmonary syndrome after exposure to deer mouse Hanta virus
Hepatitis D virus Deltavirus. Enveloped, ssRNA, negative sense, circular.
Live attenuated vaccines induce what type of immunity? Humoral and cell-mediated immunity
Killed vaccines induces what type of immunity? Humoral
What vaccines are Live attenuated? Measles, Mumps, Rubella. Sabin, VZV, Yellow Fever, Smallpox, Adenovirus
What vaccines are killed Rabies, Influenza, Salk (polio), and HAV. Mnemonic: RIP Always. SalK=Killed
Egg based vaccines Flu, MMR, Yellow fever (FRY an egg)
Recombinant vaccines HBV (antige = recombinant HBsAg)
What is Recombination Exchange of genes between 2 chromosomes by crossing over within regions of significant base sequence homology
Exchange of genes between 2 chromosomes by crossing over within regions of significant base sequence homology Recombination
What is Reassortment? When viruses with segmented genomes (eg influenza virus) exchange segments. High frequency recombination. Cause of worldwide pandemics.
When viruses with segmented genomes (eg: influenza virus) exchange segments. High frequency recombination. Cause of worldwide pandemics. Reassortment
What is Complementation? When 1 of 2 viruses that infect the cell has a mutation that results in a nonfunctional protein. The nonmutated virus "complements" the mutated one by making a functional protein that serves both viruses
When 1 of 2 viruses that infect the cell has a mutation that results in a nonfunctional protein. The nonmutated virus makes a functional protein that serves both viruses. Complementation
What is Phenotypic mixing? Genome of virus A can be coated with surface proteins of virus B. Type B protein coat determines the infectivity of the phenotypically mixed virus. However, the progency from this infection has a type A coat and is encoded by its type A genetic material.
Genome of virus A can be coated with surface proteins of virus B. Type B protein coat determines the infectivity of the phenotypically mixed virus. However, the progeny form this infection has a type A coat and is encoded by its type A genetic material. Phenotypic mixing
Negative stranded viruses Rhabdovirus, Filovirus, Arenavirus, Bunyavirus, Paramyxovirus, Orthomyxovirus, Deltavirus. "Real Foes Are Better Paralyzed Or Dead"
Segmented viruses Bunyavirus, Orthomyxovirus, Arenavirus, Reovirus. "BOAR"
Picornavirus types Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, HAV. "PEARCH on a peak"
Are Picornaviruses large or small? Small. PicoRNAvirus = small RNA virus
How are Picornaviruses manufactured? RNA is translated into 1 large polypeptide that is cleaved by proteases into functional viral proteins
Important facts about Rhinovirus Nonenveloped RNA virus (Picornavirus). Cause of common cold. >100 serotypes
Most important cause of infantile gastroenteritis Rotavirus (segmented dsRNA virus)
Major cause of acute diarrhea in the US during winter Rotavirus (segmented dsRNA)
Virus causing villous destruction with atrophy leading to decreased absorption of Na+ and water Rotavirus (dsRNA, segmented, Reovirus)
Mnemonic to remember clinical consequences of Mumps Mumps makes your parotid glands and testes as big as POM-poms. (P=parotitis, O=orchitis, M=meningitis)
Virus containing hemagglutinin and neuraminidase antigens Influenza virus
What type of vaccine is the influenza vaccine? Killed
Genetic shift (Pandemic) Reassortment of viral genome (such as when human flu A virus recombines with swine flu A virus)
Genetic drift (Epidemic) Minor changes based on random mutation
Which is more deadly Genetic shift, or Genetic drift? Sudden Shift is more deadly than graDual Drift
Txt of choice for Influenza virus Amantadine and Remantadine useful for influenza A. Zanamivir and Oseltamivir are useful for both influenza A and B
How does Rubella cause deafness? Deafness is due to failure of cochlea and spiral ganglion to develop
Travels to the CNS by migrating in a retrograde fashion up nerve axons Rabies virus
Arboviruses Viruses transmitted by ARthropods. Flavivirus, Togavirus, and Bunyavirus. "Fever Transmitted by Bites"
What is the reservoir for Yellow Fever? Monkey or human reservoir
High fever, black vomitus, and jaundice Yellow fever
Councilman bodies in the liver Yellow fever
Mnemonic to remember the types of Herpes Get herpes in a CHEVrolet: CMV, HSV, EBV, VZV
Clinical manifestations of HSV-1 Gingivostomatitis, keratoconjunctivits, temporal lobe encephalitis, herpes labialis
How is HSV-1 transmitted? Respiratory secretions, saliva
Clinical manifestations of HSV-2 Herpes genitalis, neomatal herpes
How is HSV-2 transmitted? Sexual contact, perinatal
Clinical manifestations of VZV Varicella-zoster (shingles), encephalitis, pneumonia
How is VZV transmitted? Respiratory secretions
What are the clinical manifestations of EBV? Infectious mononucleosis, Burkitt's lymphoma
How is EBV transmitted? Respiratory secretions, saliva
What are the clinical manifestations of CMV? Congenital infection, mononucleosis (negative monospot), pneumonia
How is CMV transmitted? Congenital, transfusion, sexual contact, saliva, urine, transplant
What are the clinical manifestations of HHV-8 Kaposi's sarcoma in HIV patients
How is HHV-8 transmitted? Sexual contact
Monospot test heterophile antibodies detected by agglutination of sheep RBCs
Abnormal circulating cytotoxic T cells (atypical lymphocytes). Reacting against infected B cells Mononucleosis
A smear of an opened skin vesicle to detect multinucleated giant cells Tzank test (looking for HSV1,HSV2, and VZV). "Tzanck heavens I do not have herpes"
HAV (RNA picornavirus) transmitted primarily by fecal oral route. Short incubation (3 weeks). No carriers
Mnemonic to remember Hep A Hep A: Asymptomatic (usually), Acute, Alone (no carriers, and naked ssRNA)
HBV DNA hepadnavirus. Transmitted primarily by parenteral, sexual, and maternal-fetal routes. Long incubation (3 months). Carriers. Reverse transcription occurs, however, the virion enzyme is a DNA-dependent DNA polymerase
Which Hepatitis virus can undergo reverse transcription? HBV (however, the virion enzyme is a DNA-dependent DNA polymerase)
HCV RNA flavivirus. Transmitted primarily via blood and resembles HBV in its course and severity. Carriers. Common cause if IV drug use hepatitis in the US.
Common cause of IV drug use Hepatitis in the US HCV (RNA flavivirus)
Mnemonic to remember importance of Hep C Hep C: Chronic, Carriers, Cirrhosis, Carcinoma.
HDV Deltavirus. A defective virus that requires HBsAG as its envelope. Carriers
HEV (RNA Calcivirus). Transmitted enterically and causes water-borne epidemics. High mortality rate in pregnant women.
Hepatitis to worry about in pregnant women HEV (high mortality!)
Which hepatitis viruses are transmitted fecal-orally? A and E. "The vowels hit your bowels"
Mnemonic to remember importance of Hep D Hep D: Defective, Dependent on HBV
Mnemonic to remember importance of Hep E Hep E: Enteric, Expectant mothers, Epidemics.
Which hepatitis viruses predispose a patient to chronic active hepatitis, cirrhosis, and hepatocellular carcinoma? HBV and HCV
Best test to detect active hepatitis A? IgM HAVAb. (IgM antibody to HAV)
Antigen found on surface of HBV HBsAg (continued presence of antigen indicates carrier state)
The presence of this antigen indicates continued carrier state of Hepatitis B HBsAg
Which antibody indicates immunity to Hepatitis B HBsAb (antibody to HBsAg)
Antigen associated with core of HBV HBcAg
Hepatitis B test that is positive during window period HBcAb (antibody to Hepatitis B core antigen)
IgM HBcAb is indicative of what? an indicator of recent disease
What is an important indicator of HBV transmissibility? HBeAg. "BEware"
What indicates low HBV transmissibility? HBeAb
HBeAb Indicates low transmissibility of HBV
HBeAg Indicates high transmissibility of HBV
HBcAb Antibody to HBcAg. indicates during window period.
HBsAb Indicates immunity to HBV
HBsAg indicates carrier state of HBV, or early incubation period of HBV.
During the incubation period of HBV what will be positive? HBsAg
During the Prodrome, or Acute disease phase of HBV what will be positive? HBsAg, HBcAb
What is only serologic marker during window period? HBcAb
What serologic markers indicate complete recovery from HBV HBsAb, HBcAb (IgG)
What serologic markers indicate acute HBV? HBsAg, HBcAb (IgM)
What serologic markers indicate the chronic carrier state of HBV? HBcAb (IgG), HBsAg
What does the gp41 protein do in HIV? It is an envelope protein (other is gp120). More specifically it acts during fusion of the viral envelope and cell membrane
What does gp120 protein do in HIV? It is an envelope protein (other is gp41). More specifically it is the envelope protein which binds to CD4.
What does the p24 protein do in HIV? is a rectangular neuclocapsid protein
Is the HIV genome haploid or diploid? Diploid (2 molecules of RNA)
What does the p17 protein do in HIV? It is a matrix protein
An RNA dependent DNA polymerase HIV
Presumptive diagnosis of HIV is made with? ELISA (sensitive, high false-positive rate, and low threshold) - can RULE out test. Positive results are then confirmed with Western blot assay (specific, high false-negative rate and high threshold) - Rule IN diagnosis
Which test has a high sensitivity for HIV? ELISA (can rule out) - usually is inital test
Which test has a high specificity for HIV? Western blot assay (can rule in HIV) - usually used to confirm a positive ELISA
What tests allow physicians to monitor the viral load of HIV? HIV PCR
AIDS diagnosis = < 200 CD4+, HIV positive with AIDS indicatior contition (eg: PCP), or CD4/CD8 ratio <1.5
CCR5 mutation If homozygous allows immunity to HIV. If heterozygous, have a slower HIV course. (1% Americans homozygous, 20% heterozygous)
CXCR1 mutation Rapid progression in AIDS
Reservoirs of HIV during latent phase of infection Follicular dendritic cells in germinal centers of lymph nodes
Serologic markers of Acute HIV infection Virus p24 antigen, High CD4 cells, Increasing number of Anti-p24, and Anti-gp120 antibodies
Serologic markers of latent HIV infection Anti-p24 antibodies, Anti-gp120 antibodies, Still have high number of CD4 cells
Serologic markers of Progressive HIV infection Decreasing number of CD4 lymphocytes, Decreasing amt of anti-p24 antibodies, and anti-gp120 antibodies, increasing amount of viral p24 antigen
What are opportunistic infections of the Brain in AIDS? Cryptococcal meningitis, toxoplasmosis, CMV encephalopathy, AIDS dementia, PML (JC virus)
Opportunistic infections affecting the eyes of AIDS patients CMV retinitis
Opportunistic infections affect the mouth and throat of AIDS patients Thrush, HSV, SMV, oral hariy leukoplakia (EBV)
Opportunistic infections affecting the Lungs of AIDS patients PCP, TB, Histoplasmosis
Opportunistic infections affecting the GI tract of AIDS patients Cryptosporidiosis, MAC complex, CMV colitis, non-Hodgkin's lymphoma (EVB)
Opportunistic infections affecting the Skin of AIDS patients Shingles (VZV), Kaposi's sarcoma (HHV-8)
Opportunistic infections affecting the Genitals of AIDS patients Genital herpes, warts, and cervical cancer (HPV)
Primary CNS lymphoma An intermediate to hight grade B cell lymphoma associated with EBV affecting AIDS patients. Presents with seizures, HA, cranial nerve deficits, and multicentric lesions sometimes involving the meninges.
Infectious agents that do not contain RNA or DNA Prions (consist only of proteins)
Spongiform encephalopathy Prion disease
Types of Prion disease Creutzfeldt-Jakob disease, Kuru, Scrapie, and Mad Cow disease
Conformation of prions Normal prions have alpha-helix conformation. Pathologic prions (like CJC) are beta-pleated sheets
Dominant normal flora of the Skin Staphylococcus epidermidis
Dominant normal flora of the Nose Staphylococcus aureus
Dominant normal flora of the Oropharynx Viridans streptococci
Dominant normal flora of a dental plaque Streptococcus mutans
Dominant normal flora of the colon Bacteriodes fragilis > E.coli
Dominant normal flora of the vagina Lactobacillus, colinized by E.coli and group B strep
Common causes of pneumonia in Children 6wks - 18 yrs Viruses (RSV), Mycoplasma, Chlamydia pneumoniae, Strep pneumoniae
Common causes of pneumonia in Adults (18-40yrs) Mycoplasm, Chlamydia pneumoniae, Strep pneumo
Common causes of pneumonia in Adults (40-65yrs) S.pneumo, H.influenza, Anaerobes, Viruses, Mycoplasma
Common causes of pneumonia in Elderly S.pneumo, Viruses, Anaerobes, H.influenza, Gram-negative rods
Pneumonia (hospital acquired) Staphylococcus, gram-negative rods
Pneumonia in immunocompromised Staphylococcus, gram-negative rods, fungi, viruses
Aspiration pneumonia Anaerobes
Pneumonia in alcoholic/IV drug user S.pneumoniae, Klebsiella, Staphylococcus
Post-viral pneumonia Staphylococcus, H.influenza
Neonatal pneumonia Group B streptococci, E.coli
Atypical pneumonias Mycoplasma, Legionella, Chlamydia
MCC meningitis newborns Group B streptococci
MCC meningitis Children (6mo-6yrs) Streptococcus pneumoniae
MCC meningitis Adults (6yrs-60yrs) N.meningitidis
MCC meningitis Elderly (60+) S.pneumoniae
Causes of meningitis in HIV positive individuals Cryptococcus, CMV, toxoplasmosis, JC virus
What type of meningitis has Increased opening pressure, Increased PMNs, Increased protein, and Decreased glucose Bacterial
What type of meningitis has Increased opening pressure, Increased lymphocytes, Increased protein, and decreased glucose Fungal/TB
What type of meningitis has Normal to Increased opening pressure, Increased number of lymphocytes, Normal protein, and Normal glucose Viral
Bacterial Meningitis CSF findings Increased opening pressure, Increased number of PMNs, Increased amt of protein, Decreased glucose
Fungal/TB meningitis CSF findings Increased opening pressure, Increased number of lymphocytes, Increased amt of Protein, Decreased glucose
Viral meningitis CSF findings Normal or increased opening pressure, Increased number of lymphocytes, Normal amt of protein, Normal glucose
MCC of Osteomyelitis S.aureus
Osteomyelitis in sexually active individual N.gonorrhoeae (rare), septic arthritis is more common
Osteomyelitis in diabetics and drug addicts Pseudomonas aeruginosa
Osteomyelitis in Sickle cell disease Salmonella
Osteomyelitis in persons with prosthetic replacement S.aureus and S.epidermidis
Vertebral Osteomyelitis Mycobacterium tuberculosis (Pott's disease)
UTIs in ambulatory pts E.coli (50-80%), S.saprophyticus (10-30%), Klebsiella (8-10%)
UTIs in hospital pts E.coli, Proteus, Klebsiella, Serratia, Pseudomonas
Predisposing factors to UTIs Flow obstruction, kidney surgery, catherterization, gynecologic abnormalities, diabetes, pregnancy
Fever, chills, flank pain, and CVA tenderness Pyelonephritis
Dysuria, frequency, urgency, suprapubic pain Urinary tract infection
UTI bug producing a red pigment. Is often nosocomial and drug resistant Serratia marcescens
UTI bug is 2nd leading cause of community-acquired UTI in sexually active women Staphylococcus saprophyticus
UTI bug showing metallic sheen on EMB agar E.coli (is the leading cause of UTI)
UTI bug that is often nosocomial and drug resistant Enterobacter cloacae
UTI bug that has a large mucoid capsule and viscous colonies Klebsiella pneumoniae
UTI bug that is motile, causing "swarming" on agar. also produces urease and is associated with struvite stones Proteus mirabilis
UTI bug producing a blue green pigment and fruity odor. is usually nosocomial and drug resistant Pseudomonas aeruginosa
Mnemonic to remember UTI bugs SSEEKPP (Serratia marcescens, S.saprophyticus, E.coli, Enterobacet cloacae, Klebsiella, Proteus, Psedomonas)
Leukocyte esterase positive Indicates bacterial
Nitrite test positive Indicated gram-negative
Urethritis, cervicitis, PID, prostatitis, epididymitis, arthritis, creamy purulent discharge N.gonnorrhoeae
Painless chancre primary syphilis
Fever, lymphadenopathy, skin rashes, codylomata lata secondary syphilis
Gummas, tabes dorsalis, general paresis, aortitis, argyll robertson pupil tertiary syphilis
Painful penile, vulvar, or cervical ulcers Genital herpes (HSV2)
Urethritis, cervicitis, conjunctivitis, Reiter's syndrome, PID Chlamydia Trachomatis (D-K)
Ulcers, lympadenopathy, rectal strictures Lymphogranuloma venereum (Chlamydia trachomatis L1-L3)
Vaginitis, strawberry-colored mucosa Trichomonas vaginalis
Genital warts, koilocytes Condylomata acuminata (HPV 6 and 11)
Painful genital ulcer, inguinal adenopathy Chancroid (Haemophilus ducreyi)
Noninflammatory, malodorous vaginal discharge (fishy smell), positive whiff test, clue cells Bacterial vaginosis (Gardnerella vaginalis)
Chandelier sign Cervical motion tenderness in Pelvic inflammatory disease
Top causes of PID Chlamydia trachomatis (subacute, often undiagnosed), Neisseria gonorrhoeae (acute, high fever)
Cervical motion tenderness, purulent cervical discharge PID
Salpingitis is a risk factor for: Ectopic pregnancy, infertility, chronic pelvic pain, and adhesions
Nosocomial infections: Newborn nursery CMV, RSV
Nosocomial infections: Urinary catherterization E.coli, Proteus mirabilis
Nosocomial infections: Respiratory therapy equipment Pseudomonas aeruginosa
Nosocomial infections: Work in renal dialysis unit HBV
Nosocomial infections: Hyperalimentation Candida albicans
Nosocomial infections: Water aerosols Legionella
Highest yield hints: Pus, empyema, abscess S.aureus
Highest yield hints: Pediatric infection H.influenza (including epiglottitis)
Highest yield hints: Pneumonia in cystic fibrosis, burn infection Pseudomonas
Highest yield hints: Branching rods in oral infection Actinomyces israelii
Highest yield hints: Traumatic open wound Clostridium perfringens
Highest yield hints: Surgical wound S.aureus
Highest yield hints: Dog or cat bite Pasteurella multocida
Highest yield hints: Currant jelly sputum Klebsiella
Highest yield hints: Sepsis/meningitis in newborm Group B strep
Created by: tommyparisi