Micro Flashcards
What is the stain used to visualize legionella?
Silver Stain
Is nocardia or actinomyces acid fast?
Nocardia
What agar is used for C. diptheria?
Cysteine - Tellurite agar (black colonies)
What do E. coli look like on EMB agar?
Dark purple colonies with green metalic sheen
What are common encapsulated bugs?
S. Pneumoniae H. Flu N. Meningitides E. Coli Salmonella K. pneumoniae GBS
Is listeria catalase positive?
Yes
What are some weird urease + bugs?
Cryptococcus, S. Epidermidis, S. Saprophyticus
What bacteria produce a red pigment?
S. Marcescens
What bacteria express IgA protease?
SHiN bacteria
How does shiga toxin inactivate 60S ribosome?
Removes adenine from rRNA
Does heat stabile toxin decrease reabsorption or increase secretion?
Decreases reabsorption of NaCl and H2O in the gut
How does B. Anthracis edema factor work?
Mimics adenylate cyclase
How do the toxins of V. Cholera and B. Pertussis differ?
Cholera - permanently activates Gs
Pertussis - Disables Gi
What toxins are encoded in a lysogenic phage (specialzied transduction)?
ABCDE: shigA like toxin Botulinum toxin Cholera toxin Diptheria toxin Erythrogenic toxin of S. pyogenes
Are viridans group strep bile soluble or insoluble?
Bile insoluble
What kind of hemolysis does L. monocytogenes exhibit?
Beta hemolysis (and tumbling motility)
Which strain of viridans group strep causes subacute bacterial endocarditis?
S. Sanguis (makes dextrans which bind to fibrin-platelet aggregates)
What factor is produced by Group B Strep?
CAMP factor - enlarges the area of hemolysis formed by S. Aureus.
Which bacterium has metachromatic blue-red granules?
C. Diptheriae
What bacterial spores are found in soil?
Antharax, C. perfringens, C. tetani
How does one differentiate atropine poisoning and botulism?
Atropine only blocks muscarinic receptors, so it wouldn’t have skeletal muscle weakness
What are the 3D’s of botulism?
Diplopia, Dysphagia, Dysphonia
What two types of poisoning can B. cereus cause?
Nausea/Vomiting - 1-5 hr onset (cerulide toxin)
Diarrheal - 8-18 hr onset
What forms the rocket tails of listeria?
Actin polymerization
What gram positive produces LPS?
Listeria
What granulomatous disease might show false - PPD?
Sarcoidosis, use IFN-gamma release assay
What is the key virulence factor in Mycobacterium?
Cord factor - causes serpentine growth pattern. Inhibits Mphage maturation
What is the treatment of leprosy?
Tuberculoid - Dapsone, Rifampin for 6 months
Leparomatous - Dapsone, Rifampin, clofazimine for 2-5 yrs
What enzyme does E. coli produce?
Beta galactosidase
What is Fitz-Hugh-Curtis syndrome?
Inflammation of the liver capsule. Gonoccoci
What bacteria can provide the needed factors for H. flu?
S. Aureus
What is used for H. flu mucosal infections?
Amoxicillin
What electrolyte abnormality is seen with Legionella?
Hyponatremia
What media is needed to culture legionella?
Charcol-yeast extract with Fe and Cysteine
What is a common finding in malignant otitis externa in diabetics?
Granulation tissue in the ear cannal
How does EPEC cause disease?
Adheres to apical intestinal surface and flattens villi causing malabsorption (pediatric diarrhea, rx with quinolones)
What is a key finding for EHEC?
Does not ferment sorbitol. Also usually no fever and no PMNs in stool b/c it is not invasive
What are the 4 A’s of klebsiella?
Aspiration, Abscess (lung, liver), Alcoholics, diAbetics
Do antibiotics help in Shigella? Salmonella?
Shigella - shorten duration of organism excretion
Salmonella - May prolong fecal excretion of organisms
What is the difference in inflammatory response between shigella and salmonella?
Shigella - PMN response
Salmonella - Monocytic response
Does shigella have animal reservoirs?
No
What temp does campylobacter grow at?
42 C
What temp does Yersinia grow well at?
Less than body temp
Which spirochete can be visualized with aniline dyes?
Borrelia
What population is leptospirosis common among?
Sufurs
What is Weils disease?
Icterohemorrhagic leptospirosis, jaundice, azotemia, hemorrhage, anemia
What stage of syphilis has a rash?
Secondary
What is the vector of Borellia recurentis?
louse
What is the disease and vector for R. Prowazekii?
Epidemic Typhus - Louse