March 30 - Micro Flashcards
P fimbriae
E coli virulence factor. Allows for adhesion to uroepithelium in UTIs
Bacillus anthracis morphology
Large gram positive rods that form medusa head colonies. Antiphagocytic capsule composed of D glutamate.
Diphtheria morphology
Nonmotile gram pos rods, often in clumps or V or Y shaped chains. Granules stain with aniline dyes (i.e. methylene blud)
Thayer martin medium
Selective chocolate agar with multiple antiboitics used to isolate N gonorrhea
Chocolate agar
Lysed red cells that release NAD (factor V) and hemin (factor X). Used to culture H flu
Bordet-Gengou agar
Used for pertussis
Loffler’s media
Selective for diphtheria
Tellurite plate
Differential for diphtheria
Lowenstein Jensen agar
Used to grow TB
Eaton’s agar
Grows mycoplasma, high in cholesterol
Eosin-methylene blue
Selective for gram negatives. Differential for lactose fermenters which turn a green metallic sheen.
Sorbitol macconkey
used to isolate 0157 e coli
buffered charcoal yeast
used for legionella
Sabouaud’s agar
used to grow fungi
N meningitidis prophylaxis
Done for close contacts. options are rifampin, ciprofloxacin (Adults), and IM ceftriaxone
Daptomycin
Antibioitic used to treat MRSA. Creates transmembrane channels, depolarizing cell membranes.
ADRs: myopathy, elevation of CPK.
Inactivated by surfactant so can’t be used to treat pulmonary infections.
Linezolid
Antibiotic used to treat MRSA. Inhibits 50s ribosome. ADRs: thrombocytopenia, optic neuritis, serotonin syndrome.
INH: MOA and MOR
MOA: activated by mycobacterial catalase peroxidase. Then inhibits mycolic acid synthesis.
Resistance: mutated binding site on mycolic acid synthesis enzyme results in decreased expression of catalase peroxidase
Oseltamavir
Neuraminidase inhibitor used to treat influenza A and B. Prevents release of virus from infected cells
Amantadine
Impairs uncoating and disassembly of influenza A. Increases dopamine release in PD
Aminoglycoside resistance
Bacteria produce enzymes that transfer different chemical groups to drug, decreasing ability to bind ribosomes
Waterhouse-Friderichson syndrome
Complication of meningococcemia, either in presence or absence of meningitis. Adrenal gland destruction, DIC, and shock
Alcohol as disinfectant
Disrupt cell membranes and denatures proteins. Not sporicidal
Chlorhexidine as disinfectant
Disrupts cell membranes and coagulates cytoplasm. Not sporicidal
H2O2 as disinfectant
Produces free radicals. Sporicidal
Iodine as disinfectant
Halogenates proteins and nucleic acids. Sporicidal
Proteus lab characteristics
Gram neg rod, lactose non-fermenter, H2S producer (same as salmonella)
Lactose fermenting gram neg rods
Fast fermenters: E coli, Klebsiella, enterobacter
Slow fermenters: Citrobacter, serratia
E coli and enterobacer distingushed by ecoli indole pos and enterobacter indole neg
GAS vs GBS
GAS is PYR positive
GBS is PYR negative
Bacillary angiomatosis
Caused by Bartonella henselae infection in immunocompromised. Red-purple papular lesion that mimics Kaposi sarcoma
Adenovirus presentation
Fever, congestion, conjunctivits, pharyngitis
Year round outbreaks
Bacterial vaginitis vs trichomonas vaginalis
Gardnerella vaginalis
- off white discharge iwth fishy odor
- clue cells: epitheilial cells covered with gram variable rods
Trichomonas
-thin yellow-green malodorous frothy discharge
Chlamydia trachomatis presentation
Small shallow painless ulcers initially. Followed by large painful inguinal nods
Roseola
Caused by HHV-6. Occurs in kids less than 2. High fever for 3-7 days that stops abruptly and is followed by blanching maculopapular rash
Aspiration syndromes
- Aspiration of gastric contents: acid injury and inflammation (not infection) of lung hours later
- Aspiration of oropharyngeal contents: pneumonia days later
Enterococcal endocarditis
Seen followiong cystoscopy, colonoscopy, obstetric procetures
Q fever
Caused by inhalation of Coxiella burnetii in air contaminated by animal waste.
Acute: fever for over 10 days, retroorbital HA, pneumonia, elevated LFTs, low platelets
Chronic: endocarditis in patients with valve disease
Bacteria causing lyme disease
Borrelia burgdorfei
Vi antigen
Salmonella virulence factor. Capsule that protects against opsonization adn phagocytosis
