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IDR study party 3
|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
|treatment for S.typhi?
|A bacteria that shows growth in APCs in lymph nodes can lead to very swollen “buboes” which can burst; septicemia.
|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
|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
|What are the two bad strains of V. Cholerae
|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?
|__________________ 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
|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.
|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.
|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
|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)
|Brucella _________: Most severe symptoms in humans, found in sheep and goats
|Brucella that is most likely to cause pneumonia and urdulant fevers. Most likely to disseminate to different body sites: joints, hearts
|____________ can replicate in alveolar macrophages’ cytoplasm because they can escape the phagosome
|_______________is a mild disease that is the most common consequence of a Legionella infection
|Gram - pleomorphic coccibacilli that can cause Bi-lateral inflammation with little to no sputum produced from cough
|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)
|see this in little kids where they bite each other to resolve conflict
|normal oral flora in carnivorous domestic animals, like cats and dogs
|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
|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
|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)
|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
|which 2 bacteria escapes from the phagosome, replication in cytoplasm, and cause lots of NOD-protein activated inflammation & death of cells
|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
|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
|can transition from “rough” strains that lack the O-polysaccharide of LPS to “smooth” strains that have lots of O-polysaccharide
|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
|can’t survive outside of amoeba so you have to be able to inhale this as an infected amoeba
|create a double-layer phagosome, that never fuses with a lysosome (Wrapped up in layers of RER)
|mild disease that is the most common consequence of a Legionella infection
|a much more serious condition experienced by some Legionella-infected patients following their initial “Pontiac fever” symptoms
|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)
|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
|Spread by human body lice, (humans main host); also in squirrels in eastern US/Canada
|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)
|demographic likely to get R. prowazekii
|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”
|asymptomatic; most common presentation mild flu-like symptoms. Can cause chronic endocarditis. Treat with doxycycline.
|_____ 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.
|the #1 cause of “atypical” or “walking” pneumonia and is also frequently carried asymptomatically.
|: a conjunctivitis caused by Chlamydia trachomatis that can lead to corneal scarring and blindness
|symptoms like gonorrhea, but with a thinner discharge. It’s more likely to be asymptomatic in both men and in women than gonorrhea is.
|painless lesions accompanied by regional lymph node swelling and painful lymph nodes close to initial infection site 1 – 4 weeks post-infection.
|caused by the dimorphic Malassezia furfur, which infects skin and alters color.
|Pityriasis (Tinea) versicolor
|caused by Hortaea werneckii, causes skin to darken.
|superficial infection of the hair shaft caused by Piedra hortae.
|fungal infection of fingernails and toenails caused by Trichophyton rubrum and T. mentagrophytes.
|Dermatophytes don't typically penetrate deeper, and acquire nutrition because they are ______
|an infection that forms warty pigmented lesions which grow outward from site of introduction
|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
|Fungi are cultured on specialty media, especially
|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
|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
|_______ interfere with ergosterol synthesis at an earlier step than triazoles do. Because of potential for renal damage, they’re typically only used topically
|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
|Disseminated disease most likely in pregnant women, Pacific islanders, those of African descent *and immunocompromised
|cultured and characterized microscopically as a mould producing both tuberculate macroconidia and microconidia
|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.
|Pulmonary infection flulike symptoms with fever, chills, headache, cough Disseminated disease can ulcers on oral mucosa, skin, hepatosplenomegaly
|1,3 alpha-glucan in cell wall prevents killing by neutrophils
|May have very prolonged latency (>40 years) between initial infection and onset of disseminated disease.
|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.
|A typical infection by _________ involves traumatic wounding and soil, such as with rose gardeners or people who work with sphagnum moss or wood.
|forms narrow-based yeast cells in tissue and delicate hyphae with a cluster (“flowerette”) of spores (spores) at the end of a narrow stalk.