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IDR study party 3
Question | Answer |
---|---|
What three things make up the Hemolytic uremic syndrome (HUS) | •Acute renal failure •Thrombocytopenia •Micro-angiopathichemolytic anemia |
What do the B-units of Shiga Toxin 1 and 2 bind to? | 1-intestinal epithelial cells 2-glomerular endothelial cells |
why do antibodies make E_EC worse? | H; because shiga toxins are in the operon that is turned on by Ab. |
________leading cause of septicemia caused by Gram-negative bacteria but is always the result of intestinal leakage due to trauma | E. coli |
treatment for S.typhi? | quinolones |
A bacteria that shows growth in APCs in lymph nodes can lead to very swollen “buboes” which can burst; septicemia. | Y.pestis |
In Y.pestis fleas express __________ at 25 degrees and rats express __________ at 37 degress. What is the function of each virulence factor | hemagglutinin: clots blood plasminogen activator: lyses clots and spreads disease |
treatment for Yersinia's? | macrolides or quinolones |
US outbreaks of _________________ are mainly associated with consumption of raw oysters | V. parahaemolyticus |
4 Things that cause necrotizing fasciitis: | 1.Streptococcus pyogenes (Gram-positive coccus) 2.Clostridium perfringens (spore-forming, strictly anaerobic bacillus) 3.Acinetobacter baumannii (Gram-negative coccobacillus; extremely antibiotic resistant) 4.Vibrio vulnificius-Gram-negative curved rod |
drug treatment for Vibrio's | Macrolides and tetracyclines most commonly used to treat infections |
Toxin in Vibrio that allows bacteria to adhere to intestinal epithelial surface | toxin-coregulated pilus |
What are the two bad strains of V. Cholerae | 01, 0139 |
Why are the 01 and 0139 strains of V.cholerae more virlulent? | becasue they have dubplications of the A/B toxin genes which means more expression of the toxins |
3-6 liters of rice water diarrhea per day can lead to these sxm's in people with v.cholerae | severe dehydration, possibly hypovolemic shock |
is V. parahaemolyticus an infection or intoxication? | infection |
__________________ requires high salt concentrations to grow and so can’t grow on standard media. Virulent strains make a hemolysin that’s effective against human blood cells but not other mammalian blood cells | V. parahaemolyticus |
two ways a person can get necrotizing fasciitis from v. vulnificius | traumatic inoculation or as a sequela of a gastroenteritis |
_________________ are very fastidious, and can only be cultured in a “campy jar” that creates a 5% O2, 10% CO2 environment. samples found in gram stained stool. | Campylobacters |
B. burgdorferi 2 key virulence factors and their function | OspA leads to the colonization of tick guts, expressed at 25 C OspC leads to the spread from tick to mammals, expressed at 37 C |
Acrodermatitis chronica atrophicans is associated with what disease? | Lyme disease (more often seen in Europe) |
Laboratory Criteria for Diagnosis of lyme disease | Isolation of Borrelia burgdorferi OR Demonstration of diagnostic levels of immunoglobulin M (IgM) or IgG antibodies to the spirochetes OR Significant increase in antibody titer between acute and convalescent serum samples |
Clinical Case Definition of Lyme disease | Erythema migrans (≈5 cm in diameter) AND/OR At least one late manifestation (i.e., musculoskeletal, nervous system, or cardiovascular involvement) and laboratory confirmation of infection. |
what are the treatment of primary, secondary, tertiary lyme disease? | Primary and secondary: penicillin and doxycycline tertiary: Ab not useful, manage sxm's |
what is Weil's Disease | A severe leptospirosis infection with liver, kidney, and meningeal involvement |
_______________ is acquired by skin exposure to water containing urine from infected animals. | Leptospirosis |
treatment for leptospirosis | Penicillin or penicillin + doxycycline |
you get in a bar fight and pop the fucker in the teeth, what are you gonna get | Eikenella corrodens |
two bacteria you can get from a cat or dog bite that have similar sxm's | Pasteurella multocida , Capnocytophaga |
are very small, irregularly-shaped Gram-negative bacteria that can replicate inside of macrophages (Intracellular pathogen) | Francisella tularensis |
Brucella _________: Most severe symptoms in humans, found in sheep and goats | melitensis |
Brucella that is most likely to cause pneumonia and urdulant fevers. Most likely to disseminate to different body sites: joints, hearts | Brucella melitensis |
____________ can replicate in alveolar macrophages’ cytoplasm because they can escape the phagosome | Legionella |
_______________is a mild disease that is the most common consequence of a Legionella infection | Pontiac fever |
Gram - pleomorphic coccibacilli that can cause Bi-lateral inflammation with little to no sputum produced from cough | Legionnaires’ Disease |
Who gets Legionella infections and why? | Especially older people with a history of smoking (Reduced ciliary beating) and alcohol consumption (Reduced liver function) |
treatment of legionella? | Treat with a macrolide or a quinolone, NOT a beta-lactam |
are small, Gram-negative bacteria that are normal oral flora in humans, and very inflamed infection if traumatically inoculated under skin (like from a bite) | Eikenella corrodens |
see this in little kids where they bite each other to resolve conflict | Eikenella corrodens |
normal oral flora in carnivorous domestic animals, like cats and dogs | Pasteurella multocida |
most common symptom of Pasteurella multocida | cellulitis and swollen lymph node closest to bite site |
Pasteurella cultured best on what kind of media | blood or chocolate agar |
intracellular bacteria that must have CO2 to grow in culture; contracted from cat/dogs with symptoms similar to Pasteurella | Capnocytophaga |
causative agent of cat scratch fever; swollen, warty-like lesion at site of cat scratch or bite (or broken skin infected by cat flea feces) progresses to lymphadenopathy of region lymph node, slight fever | Bartonella henselae |
abrupt onset of fever, headache, mylagias and joint pain 2-10 days following bite, and ~3-4 days after these symptoms, petechial progressing to purulent papular rash develops on hands and feet (even if distant from original bite site) | Streptobacillus monoliformis |
criteria to diagnose Streptobacillus monoliformis | rodent bite + rash + arthralgias |
gram stain of Streptobacillus monoliformis looks like what | plemorphic - lots of different shapes |
treatment for Streptobacillus monoliformis? | treat with any drug (no resistance reported) ASAP |
very small, irregularly-shaped Gram-negative bacteria that can replicate inside of macrophages | Francisella tularensis |
which 2 bacteria escapes from the phagosome, replication in cytoplasm, and cause lots of NOD-protein activated inflammation & death of cells | Francisella, Brucella |
3 key symptoms of Francisella tularemia | ulceroglandular tularemia, oculoglandular tularemia, pulmonary tularemia |
what animals does Francisella infect? | infects rabbits, cats, and Ixodes ticks |
where is Francisella most common | Southern Midwest |
intracellular bacteria that grow in reproductive tissues of non-human mammals, can be aersolized from those body fluids, and then infect humans who inhale them | Brucella |
can transition from “rough” strains that lack the O-polysaccharide of LPS to “smooth” strains that have lots of O-polysaccharide | Brucella |
Undulant fever” of __________ due to immune responses to O-chain of smooth strain switch to rough switch to new O-chain new immune response….and the cycle repeats | Brucella |
can’t survive outside of amoeba so you have to be able to inhale this as an infected amoeba | Legionella |
create a double-layer phagosome, that never fuses with a lysosome (Wrapped up in layers of RER) | Legionella |
mild disease that is the most common consequence of a Legionella infection | Pontiac Fever |
a much more serious condition experienced by some Legionella-infected patients following their initial “Pontiac fever” symptoms | Legionnaire's Disease |
Who gets Legionella infections? | older people with a history of smoking and alcohol consumption. |
how do I get a legionella infection? | Anything that aerosolizes standing cool fresh (not chlorinated) water can inhalation of Legionella-infected amoebae |
how to visualize/detect legionella | Fluorescent stains or “silver staining” used to visualize bacteria in sputum or BAL samples. Legionella-specific antigens passed in urine of infected patients for 1 month – 1 year. PCR for Legionella-specific genes in sputum or BAL sample also works. |
how to grow legionella | Grow on buffered-charcoal yeast extract (BCYE) agar with antifungal additives. Legionella is very fastidious, and takes >1 week to grow into glossy white “ground glass” colonies. |
causes Rocky Mountain Spotted Fever, spread by American dog tick. Symptoms = high fever, classic rash, myalgias, headaches (possibly with photophobia) | Rickettsia rickettsii |
what causes High fever, severe headache, mylagias + “rose spots” rash because of vasculitis from growth in endothelial cells High fever lasts ~2 weeks, mylagias can persist for 2 – 3 months | Rickettsia prowazekii |
Spread by human body lice, (humans main host); also in squirrels in eastern US/Canada | Rickettsia prowazekii |
which bacteria causes symptoms that can recur years after initial infection because of declining immune response, but are much milder on recurrence (=Brill-Zinsser disease) | R. prowazekii |
demographic likely to get R. prowazekii | homeless |
Endemic/murine typhus symptoms look similar to those caused by R. prowazekii but are less severe, with symptoms lasting <1 month and not recurring | R. typhi/R. felis |
spread by Ixodes species ticks and by “Lone Star” ticks that fed on infected mice or deer | Ehrlichia and Anaplasma |
“Morulae” are clumps of bacteria growing in vacuoles in _______ and _______ infected WBC cells that can be seen in Giemsa-stained samples of patient WBCs (sometimes). | Ehrlichia and Anaplasma |
causes “Q fever” | Coxiella burnetii |
asymptomatic; most common presentation mild flu-like symptoms. Can cause chronic endocarditis. Treat with doxycycline. | Coxiella burnetii |
_____ can be inhaled but all _____ must be transmitted via arthropod bite | coxiella, rickettsia and erlichia |
Mycoplasma and Ureaplasma can make their own ______, but Chlamydia and Chlamydophila can’t and must use____ made by their host cells. | ATP |
the #1 cause of “atypical” or “walking” pneumonia and is also frequently carried asymptomatically. | Mycoplasma pneumoniae |
: a conjunctivitis caused by Chlamydia trachomatis that can lead to corneal scarring and blindness | Trachoma |
symptoms like gonorrhea, but with a thinner discharge. It’s more likely to be asymptomatic in both men and in women than gonorrhea is. | chlamydia |
painless lesions accompanied by regional lymph node swelling and painful lymph nodes close to initial infection site 1 – 4 weeks post-infection. | lymphogranulum venerum |
caused by the dimorphic Malassezia furfur, which infects skin and alters color. | Pityriasis (Tinea) versicolor |
caused by Hortaea werneckii, causes skin to darken. | Tinea Nigra |
superficial infection of the hair shaft caused by Piedra hortae. | Black piedra |
fungal infection of fingernails and toenails caused by Trichophyton rubrum and T. mentagrophytes. | Onychomycosis |
Dermatophytes don't typically penetrate deeper, and acquire nutrition because they are ______ | keratinolytic |
an infection that forms warty pigmented lesions which grow outward from site of introduction | Chromoblastomycosis |
Mycetomas including the most common one, _________, may be painful or not, but even painless ones can do a lot of damage to deeper tissues and bones | Madura foot |
Fungi are cultured on specialty media, especially | SDA |
what are main stains used to visualze fungi with microscopy | Silver stain and Calcofluor White |
bind to and lyse ergosterol in fungal cell membrane membrane destruction | polyenes i.e. amphotericin B |
stop synthesis of ergosterol, can be used topically or taken orally | azole |
stop synthesis of beta-glucans in fungal cell wall, can only be administered via IV | echinocandins like capsofungin |
______ is converted to ________ in cell by cytosine deaminase, 5-FU stops DNA and RNA synthesis in fungi | flucytosine, 5fu |
_______ interfere with ergosterol synthesis at an earlier step than triazoles do. Because of potential for renal damage, they’re typically only used topically | allylamines |
Example of allylamine | Terabinafine, the active ingredient in the anti-Athlete’s foot infection Lamisil. |
Inhaled mold spores go to alevoli, differentiate into yeast forms which avoid phagocytosis based on size and WI-1 shedding | Blastomyces |
Disseminated disease most likely in pregnant women, Pacific islanders, those of African descent *and immunocompromised | Coccidioides |
cultured and characterized microscopically as a mould producing both tuberculate macroconidia and microconidia | H. capsulatum |
soil fungus endemic to river valleys worldwide, and to the Mississippi, Missouri and Ohio river valleys in the US. This soil is enriched in nitrate from bird droppings. | Histoplasma capsulatum |
Pulmonary infection flulike symptoms with fever, chills, headache, cough Disseminated disease can ulcers on oral mucosa, skin, hepatosplenomegaly | Histoplasma |
1,3 alpha-glucan in cell wall prevents killing by neutrophils | Paracoccidioides |
May have very prolonged latency (>40 years) between initial infection and onset of disseminated disease. | Paracoccidioides |
A KOH wet mount of pus or superficial scrapings from mucosal lesions detects "Pilot’s wheel" type yeast cells. The “Pilots wheel” is a mother cell producing multiple daughter cells by budding. | Paracoccidioides |
A typical infection by _________ involves traumatic wounding and soil, such as with rose gardeners or people who work with sphagnum moss or wood. | Sporothrix schenckii |
forms narrow-based yeast cells in tissue and delicate hyphae with a cluster (“flowerette”) of spores (spores) at the end of a narrow stalk. | S. schenckii |