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403 Cards in this Set
- Front
- Back
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Function of catalase?
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Convert H2O2 --> H2O
Counteracts neutrophils ability to kill bacteria |
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Protein A found in?
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Staph--> binds Fc of IgG to prevent Ag binding
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Why is penicillin ineffective in treating Staph?
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Contain B-lactamases & penicillin-binding protein
Hydrolyze penicllins & allow continued peptidoglycan synthesis |
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Order of antibiotic choice in staph?
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1. Methicillin
2. Vancomycin 3. Clindamycin |
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Toxic shock syndrome found in which 2 organisms?
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Staph & Strep
TSS toxin= superantigen Bind to MHC II on APCs --> Causes massive T-cell response & Release of cytokines |
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Most common form of food poisoning?
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Staph
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Food poisoning w/ short incubation period, 4-6 hr onset, severe abdominal stress, diarrhea & no fever?
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Staph
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Which species are Novobiocin sensitive?
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1. S. aureus
2. S. epidermidis |
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Which specie ferments mannitol?
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S. aureus
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How do you differentiate between staph species?
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Coagulase test --> S. aureus (+)
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Which strep appears in pairs?
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S. pneumonia = diplococci
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Most strep are aerotolerant, which is the exception?
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Peptostreptococcus = anaerobic
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Staph saprophyticus causes?
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UTIs (2nd most common cause)
Most common cause: E coli |
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Which strep appear in the Lancefield groups?
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beta-hemolytic strep only
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Alpha hemolytic strep appear how on bap?
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Greenish zone around colony
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Which species are alpha-hemolytic?
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S. viridans, S. mitis, S. mutans & S. penumonia
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S. pyogenes is part of which Lancefield group?
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Group A strep
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S. agalactiae is part of which Lancefield group?
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Group B
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What are the streptolysins found in strep species?
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-Streptolysin O = O2 labile & antigenic
-Streptolysin S = O2 stabile & non-antigenic |
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Which strep is bacitracin sensitive?
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Group A strep: S. pyogenes
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Which strep is optochin resistant?
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S. viridans
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Clinical manifestations of scarlet fever include? caused by?
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S. pyogenes
Sore throat & skin rash, usually no fever No rash on face |
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S. agalactiae (Group B strep) cause?
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Neonatal bacteremia, pneumonia & meningitis
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Rheumatic fever is caused by? What is clincial histopathologic hallmark?
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S. pyogenes-- Mitral stenosis
Ab formed against strep Ag that attack heart |
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Most common cause of subacute bacterial endocarditis?
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Alpha hemolytic strep (S. viridins)
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Most common agent in endo infections?
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Enterococci (S. faecalis)
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Most common cause of bacterial pneumonia?
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S. pneumonia
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How do you distinguish between staph & strep?
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Catalase (+) = Staph
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2 methods for culturing Neisseria?
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1. Chocolate agar
2. Thayer-Martin agar |
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Protein I is found in which species?
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N. gonorrheae
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IgA protease is found in which 2 species?
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1. N. meningitidis
2. N. gonorrheae |
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LPS (endotoxin) causes?
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-Releases Lipid A when cell lyses
-Hosts produce IL-1 & TNF -Inflammation, fever & shock |
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Opthalmia neonatorum is caused by which organism?
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N. gonorrheae-- eye infection
Treatment= 1% silver nitrate |
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Pili are found in which species?
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Neisseria
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How is meningitis caused by N. meningitidis diagnosed?
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Lumbar puncture & gram stain CSF
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Which 2 species form spores?
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1. Bacillus
2. Clostridium |
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Minor cause of food poisoning in 2 phases: emetic & diarrheal?
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B. cereus
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Which bacteria serves as a biological indicator for sterilization process?
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B. stearothermophilus
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Which is the ONLY bacteria w/ a poly-D-Glu (polypeptide) capsule?
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B. anthracis
pXO2 plasmid |
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Which combinations of B. antrhacis exotoxins are inactive?
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EF, PA or LF alone
EF & LF |
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Which type of anthrax is most common?
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Cutaneous anthrax
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Woolsorter disease is caused by which organism?
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Pulmonary anthrax-- B. anthracis
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C. perfringens causes?
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Gas gangrene, clostridial endometritis & food poisoning
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C. difficule causes?
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Pseudomembranous enterocolitis due to antibiotic use
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Tetanospasm causes?
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Exotoxin-- inhibits inhibitory transmitters (glycine) --> SPASTIC PARALYSIS
C. tetani |
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Most potent toxin known?
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Botulism toxin-- causes flaccid paralysis
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Which organism exhibits double zone of hemolysis?
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C. perfringens
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Hyperbaric O2 treatment is used to kill which organism?
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C. perfringens
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Which organism is motile at 30 or below and psychrophilic?
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Listeria monocytogenes
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Rare but lethal form of food poisoning found in dairy products, poultry, fish & raw vegetables?
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Listeria monocytogenes
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Which organism is used in treatment of oral ulceration in Behcet's disease?
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Lactobacillus
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Which toxin is produced as a result of a gene acquired from a bacteriophage?
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C. diptheria toxin-- inactivates EF2 (translation)
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Tox gene is necessary for virulence of which organism?
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C. diptheria toxin
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Which organism produces a skin rash similar to & indistinguishable from impetigo? (Along w/ neck swelling, paralysis & airway obstruction)
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C. diptheria
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When are antibiotics used regarding C. diptheria?
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Infection-- treat w/ antitoxin (antibiotics second line of defense)
Carriers-- treat w/ antibiotics |
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Which organism lacks a rigid cell well & requires cholesterol for growth?
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Mycoplasma
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Why are mycoplasma not affected by penicillins or cephalosporins?
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No rigid cell wall
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M. hominis causes?
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PID
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M. pneumonia causes?
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primary atypical pneumonia
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Ureaplasma urealyticum causes?
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Non-gonococcal urethritis
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In chlamydia, what is the first infectious particle that comes in contact w/ the host?
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Elementary body --> Reticulate body --> multiplies --> new Elementary body --> EB lyses cell --> death
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3 diseases caused by Chlamydia tracomatis?
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1. Lymphogranuloma Venereum (LGV)
2. Trachoma 3. Inclusion conjunctivitis |
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Which gram (-) organism is sensitive to sulfonamides & contains glycogen granules?
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Chlamydia tracomatis
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How is trachoma transmitted?
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Finger to eye, flies, linens
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In which Chlamydia disease is eventual blindness seen?
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Trachoma
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In which Chlamydial disease can transmission occur from mom --> newborn or adults through sex?
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Inclusion conjunctivitis
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What is common between both trachoma & inclusion conjunctivitis?
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Inflammation of cornea
Trachoma-- blindness Inclusion conjunctivitis--not chronic, no blindness |
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Lymphogranuloma venereum is more common in men and women? Transmission by?
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More common in men
Transmission = sex |
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Herpetiform lesion on genitalia that heals without scarring is seen in which form of Chlamydia?
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Lymphogranuloma venereum
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Which species is transmitted by inhalation of dried bird feces?
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Chlamydophilia psittaci
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Which disease can range from inapparent infection --> severe chills, fever & headache & atypical pneumonia that resembles influenza?
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Psitticosis
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What causes epidemic typhus?
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Rickettsia prowazekki
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What causes endemic typhus?
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Rickettsia typhi
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What causes rocky mountain spotted fever?
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Rickettsia rickettsia
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Coxiella burnetti causes?
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Q fever
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Which organism is gram (-) but stains better with Giemsa, Macchiavello & Gimenez?
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Rickettsiae
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What is the vector for Rickettsia proqazekii?
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Human body louse (epidemic typhus)
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What is the vector for Rickettsiae typhi?
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rat flea & rat louse (endemic typhus)
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What is the vector for Rickettsiae rickettsii?
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Ixodid (hard) tick (rocky mountain spotted fever)
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Transmission of Coxiella burnetii?
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Aerosols from urine, feces & animal hides, occasionally infected milk
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Rash is not present in which Rickettsiae disease?
Also, does not require arthropod vector. |
Q fever (Coxiella burnetti)
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Undulant fever is caused by which organism?
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Brucellae
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Which bacteria is resistant to sulfonamides & glycogen is absent from inclusion?
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Chlamydophilia psittaci
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Metachromatic granules present in which bacteria?
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C. diptheria
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Chloramphenicol causes what problem?
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Aplastic anemia
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Brucella species are normally found in humans as hosts?
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False
B. melitenis-- goats & sheep (acute & most severe-- highest pathogenicity) |
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How is brucellae transmitted?
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-unpasteurized milk
-direct contact w/ infected animals -aerosol MOST COMMON: abrasions in skin, conjunctival exposure & inhalation |
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Which organism has TB-like granulomas?
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Brucella
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What virulence factors does Brucella contain?
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LPS -- no other virulence factors
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What is the major test used for diagnosis of Brucella?
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Agglutination test using heat killed brucella
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Fraction I is found in what species?
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Y. pestis -- main Ag in both immunity & virulence; found on slime layer (37C)
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VW Ag system found in which organism?
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Y. pestis (antiphagocytic in absence of envelope)
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Which bacteria produces bacteriocin?
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Y. pestis--> toxic to some bacteria
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Which 2 organisms are coagulase (+)?
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1. S. aureus
2. Y. pestis |
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Vector of Y. pestis?
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Rat flea
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Types of transmission of Y. pestis?
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1. Aerosol
2. Flea bite-- most common form 3. Contact w/ infected animal |
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Buboes are found in which disease?
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Bubonic plague-- Y. pestis
Large painful LN w/ intense inflammation & sometimes necrosis |
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Why is isolation mandatory from bubonic plaque?
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Spread by aerosol to develop pneumonic plague
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Fatality rate is highest in bubonic or pneumonic plague?
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Bubonic-- 50% in untreated 3-5 days
Pneumonic-- 100% untreated 3 days |
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Lungs heavy, filled w/ fluid & bloody frothy sputum presents in which diseas?
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Pneumonic plague
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What diagnostic tests are done for Y. pestis?
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1. Fluorescent Ab test
2. Wayson's stain-- bipolar stain |
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Which species is motile at 25C?
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Y. entercolitica
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2 diseases caused by Y. entercolitica?
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1. Enterocolitis
2. Mesenteric adentitis |
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Which organism causes a right sided aabdominal pain that resembles acute apendicitis?
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Y. entercolitica
(Also S. typhi- typhoid (enteric) fever) |
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Food poisoning associated w/ raw or undercooked pork resulting in fever, watery to bloody diarrhea & severe abdominal pain resembling appendicitis?
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Y. entercolitica
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Which organism requires cysteine for growth?
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Francisella tularensis
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Most common route of transmission of infection w/ Francisella tularensis?
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Direct contact w/ jack rabbits
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Gray pseudomembrane is caused by which organism?
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C. diptheria
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Can Francisella tularensis be transmitted by aerosol?
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No-- not from person to person
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What is the most serious form of tularemia?
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Typhoidal tularemia
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What is most common form of tularemia?
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Ulceroglandular tularemia-- ulcers on skin, large lymph nodes
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Which form of tularemia is most frequently seen as a result of dissemination of focal infection?
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Pneumonitis tularemia
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What is the most common organism isolated from infection human wound by dogs & cats?
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Pasteurella multocida
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What is the most common disease caused by a microorganism in the world?
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Tuberculosis
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Ziehl-Neelsen stain works on?
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Acid-fast bacilli
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What are the 3 components of a gram stain?
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1. Crystal violet
2. Iodine 3. Saffrin |
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What are 3 components of Ziehl-Neelson stain?
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1. Carbol fuschin
2. Acid alcohol 3. Methylene blue |
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How is cell wall of acid fast bacilli different from gram (+) or (-) bacteria?
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Acid fast --> high lipid content (waxes)
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Which organism lacks a capsule & produces no toxins?
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Mycobacteria
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Wax D is found in which organism & induces what type of reaction?
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Mycobacterium
-Wax D induces delayed type hypersensitivity reaction |
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Cord factor is present in which organism & how does it contibute to virulence?
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Cord factor = trehalose-6,6-dimycolate
-Inhibits leukocyte migration -Chronic granulomas |
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Where does M. tuberculosis initially infect?
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Lungs (obligate aerobes)
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Major defense against intracellular pathogens?
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Cell mediated immunity
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What happens to majority of people that get infected w/ TB?
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Only 5-10% of those infected w/ TB get disease
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What happens in exudative type of TB?
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Acute inflammation --> exudate absorbed OR massive necrosis --> Miliary TB
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What happens in productive type of TB?
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Chronic granuloma --> caseous necrosis --> tubercule breaks off --> Miliary TB
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Majority of people that come down w/ TB get which form of the disease?
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85% Pulmonary-- fatigue, weight loss, fever, chronic cough, spitting blood
15% Miliary-- lesions spread throuhg body |
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What does a positive PPD indicate?
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Past infection w/ mycobacteria --> Not active disease
Must do chest X-ray to confirm |
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> 5 mm PPD indicates positive in?
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HIV or immunocompromised
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> 10 mm PPD is positive in?
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People who work w/ mycobacterium or come from a country where it's prevalent
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>15 mm PPD is positive in?
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Anyone
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Which 2 media are used to culture TB?
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1. Lowenstein-Jensen
2. Middlebrook |
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Doubling time of TB-- quick or slow?
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Slow-- > 12 hrs
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Which organism is Niacin (+)?
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M. tuberculosis
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Treatment for TB?
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3-4 drugs --> prevent resistance
6-9 months because difficult to get rid of First & second line drugs Most often combo: INH + Rifampin + pyrazinamide |
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First line drugs used for TB?
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RIPES
1. Rifampin 2. Izonazid 3. Pyrazinamide 4. Ethambutal-- bacteriostatic 5. Streptomycin |
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Second line drugs of TB?
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CCCOKE
1. Ciproflaxin 2. Caproeomycin 3. Cycloserine 4. Ofloxacin 5. Kanamycin 6. Ethionamide |
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Vaccine used for TB?
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BCG vaccine -- live attenuated M. bovis
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Hansen's bacillus is also known as?
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Mycobacterium leprae
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Leprosy primarily affects?
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Cooler body parts like skin & nerves
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What are the 2 types of disease in M. leprae
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1. Lepromatous
2. Tuberculoid |
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Treatment of leprosy?
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Dapsone
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M. bovis is or is not virulent in humans? And produces disease similar to?
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Highly virulent in humans
Indistinguishable from TB |
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Mycobacteria avium-intracellular causes?
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TB-like disease in AIDS
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Leading cause of UTIs & bacteremia?
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Enterics
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Properties common to all enterics? (3)
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1. Ferment glucose (Except pseudomonas)
2. Reduce nitrates --> nitrates 3. Oxidase (-) |
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O antigens of enterics?
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LPS
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H antigens of enterics?
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Flagellar protein
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Which microorganism exhibits phase variation motility to evade the immune system?
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Salmonella
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K & Vi antigens of enterics?
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Capsule
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#1 cause of UTIs?
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Nepropathogenic E. coli (NPEC)
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Traveler's diarrhea-- several days-- caused by?
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Enterotoxigenic E. coli (ETEC)
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Virulence factors of enterotoxigenic E. coli (ETEC)?
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1. LT= heat labile toxin
- Activate AC --> cAMP 2. ST = heat stable toxin - Activate GC --> cGMP CAUSE HYPERSECRETION OF FLUIDS LT = like CHOLERA (rice water stool) |
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Infantile diarrhea is caused by?
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Enteropathogenic E. coli (EPEC)
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Which organism has a verotoxin similar to Shigella dysenteriae toxin?
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Enterohemorrhagic E. coli (EHEC)
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Severe, bloody diarrhea associated w/ undercooked ground beef, raw milk & apple cider is caused by?
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Enterohemorrhagic E. coli (EHEC)
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Most common serotype of EHEC in US?
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0157:H7
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Diarrhea in young children similar to mild "shigellosis" is caused by?
-Fever Bloody diarhhea w/ WBC |
Enteroinvasive E. coli (EIEC)
- Main virulence factor is encoded in plasmid shared by both EIEC & shigella |
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Enteroaggregative E. coli (EAEC) causes?
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Acute/chronic diarrhea w/ watery stools
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2nd most common organism to cause neonatal meningitis?
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E. coli
75% have K1 capsular Ag-- similar to N. meningitidis |
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Lab diagnosis of E. coli?
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MacConkey's agar --> pink colonies
-Lactose (+) |
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How do you determine which antibiotics are best for which strain when treating E. coli infections?
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Antibiotic susceptibility testing is essential
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Renal failure, (uremia), hemolytic anemia & thrombocytopenia are seen in which organism?
|
Enterohemorrhagic E. coli (EHEC)
Hemolytic uremic syndrome |
|
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Which bacteria has large gelatinous capsule, non-motile?
|
Klebsiella pneumoniae
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Hemorrhagic, necrotizing lungs (lobar pneumonia) w/ thick red sputum like "currant jelly" is seen in which organism?
|
Klebsiella pneumoniae
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Which organism is H2S (+) & lactose (-)?
|
Salmonella
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Salmonella typhi vs. Shigella-- SIMILARITIES (2)
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1. Proliferate well in small intestine
2 Multiply in macrophages |
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Salmonella typhi vs. Shigell-- DIFFERENCES
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1. Salmonella-- many must be ingested
Shigella-- few may be ingested 2. Shigella never invades blood 3. Shigella- NON-motile |
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Incubation of 1-2 weeks, high fever, "rose spots", early-constipation & late-bloody diarrhea is caused by?
|
Salmonella typhi
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Which type of salmonella involves a carrier state?
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S. typhi
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S. cholera-suis causes?
|
BACTEREMIA
-usually pts w/ chronic disease -Rapid dissemination, spiking fever -Focal lesions -No diarrhea* |
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Which form of salmonellai has usually has no diarrhea?
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S. cholerae-suis (bacteremia)
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Most common type of salmonella infections?
|
S. typhimurium
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Food poisoning w/ incubation of 6-48 hrs (Abrupt onset), vomiting, diarrhea, headache, low grade fever-- usually caused by eggs, mayo, chicken, pet turtles?
|
S. typhimurium-- enterocolitis
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Most common shigella in US?
|
S. sonnei
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Treat carriers w/ antibiotics?
|
yes-- to eliminate organism:
-C. diptheria -S. typhimurium |
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Which disease is considered a "disease of institutions"? (day care, mentail institutes, jail)
|
Shigellosis
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Sudden onset of abdominal pain, fever, watery diarrhea, blood, mucous (pus), rectal spasms?
|
Shigellosis-- S. dysenteriae
Blood + pus = dysentery |
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Virulence of shigella?
|
LPS
Exotoxin-- similar to verotoxin of E. coli -Enterotoxic-> diarrhea -Neurotoxic--> meningismus |
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Which organism has extracellular DNAse that gives bright red pigment?
|
Serratia marcescens
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Serratia marcescens is often seen as?
|
Secondary infection in immunocompromised & nosocomial
(antibiotic resistance) |
|
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Proteus-Morganella-Providencia commonly cause?
|
UTIs (especially proteus)
|
|
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Kidney stones caused by urease production are a result of which organism?
|
Proteus-Morganella-Providencia
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Which organism has spreading motility that causes bad odor?
|
Proteus
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Which organism has fruity odor?
|
Pseudomonas aeruginosa
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Which enteric does not ferment glucose or lactose?
|
Pseudomonas aeruginosa
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Second most common organism in burn infections w/ green pus?
|
Pseudomonas aeruginosa
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Which 2 toxins inhibit protein synthesis via EF2?
|
1. C. diphtheria
2. Pseudomonas aeruginosa |
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Which organisms are salt tolerant? (3)
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1. Staphylococci
2. Enterococci 3. Vibrios = halophilic (except V. cholerae) |
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Which organism grows at high alkalinity?
|
V. cholerae
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Similarities of V. cholerae w/ salmonella & shigella? (2)
|
1. Many organisms ingested (Salmonella)
2. Never invades blood (Shigella) |
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Food poisoning 1-4 incubation, "Rice water" stool-- watery, non-bloody diarrhea, w/ flecks of mucus... typically caused by undercooked shellfish or meat & water?
|
V. cholerae
|
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Which toxin is similar to LT toxin of E. coli?
|
Enterotoxin of V. cholerae
Increase cAMP --> Loss of fluids & electrolytes |
|
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Transmission of Campylobacter jejuni?
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1. Food & water
2. Infected animals 3. Oral-anal sex |
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Enterotoxin of campylobacter is similar to?
|
Cholera
|
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Enterocolitis of C. jejuni may resemble?
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dysentery (shigella)
|
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Survival of H. pylori in stomach is due to? (3)
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1. Urease-- protective cloud of ammonia
2. Mucinase-- eases penetration 3. Rapid motility-- shorterns time in acid |
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Which enterics have no bactermia/dissemination? (3)
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1. Shigella
2. V. cholerae 3. H. pylori |
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Sulfur granules w/ yellow pus are seen as a result of which organism?
|
Actinomyces
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Lumpy jaw is caused by which organism?
|
Actinomyces
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Which organisms are acid-fast?
|
1. Mycobacterium
2. Nocardiosis |
|
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2 bacteria which resemble fungi?
|
1. Actinomyces
2. Nocardiosis |
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Lumpy jaw is characteristic of an infection w/ which organism?
|
Actinomyces
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Treatment of actinmocyes infection?
|
Drainage & penicllin/tetracycline
|
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Treatment of nocardiosis?
|
Drainage & sulfa drugs
|
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Which organisms produce skin lesions w/ circular shape & were once thought to be caused by worms?
|
Dermatophytoses
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Which fungus infects skin, hair (scalp)?
|
Microsporum
|
|
|
Woods light which gives off a blue-green fluoresence is used to detect which organism?
|
Microsporum
|
|
|
Infection of skin, hair & nails is caused by?
|
Trichophyton
|
|
|
Infection of skin & nails is caused by?
|
Epidermophyton
|
|
|
Macroconidia that are large, multicellular & spindle shaped are seen in?
|
Microsporum
|
|
|
2 trichopyton species?
|
1. T. mentagrophytes
2. T. rubrum |
|
|
Macroconidia which are club shaped are found in which organism?
|
Epidermophyton floccosum
|
|
|
What is the name of an infection that results from inappropriate use of topical steriods that can exacerbate tinea cruris?
|
Tinea incognito
|
|
|
Is topical treatment of dermatophytoses curative?
|
No-- but are effective
-Salicylic acid -Benzoic acid -Clotrimazole |
|
|
What oral treatment is used for dermatophytoses?
|
Griseoflucin (antibiotic)
|
|
|
Superficial infection of the stratum corneum is caused by/
|
Malassezia furfur
|
|
|
Spaghetti & meatballs under a microscope is characteristic of?
|
Malassezia furfur
|
|
|
All systemic fungi are dimorphic except?
|
Cryptococcus neoformans
|
|
|
Similarites seen in systemic fungi?
|
1. Habitat = soil, bird droppings
2. Transmission = inhalation 3. Disease = pulmonary & dissemination |
|
|
Which organism is best seen w/ India ink?
|
Cryptococcus neoformans
|
|
|
Which organisms are urease (+)
|
1. Proteus-Morganella-Providencia
2. H. pylori 3. Cryptococcus neoformans |
|
|
Bird droppings are a habitat for which 2 organisms?
|
1. Cryptococcus neoformans
2. Histoplasma capsulatum |
|
|
Which organism is neurotropic & often results in "fried egg" appearance lesions in brain or meningitis?
|
Cryptococcus neoformans
|
|
|
Who is at particularly high risk for infection w/ Cryptococcus?
|
AIDS pts,diabetes, cancer, pts w/ immunosupressive therapy
|
|
|
Which organism has characteristic "figure 8 nucleus"?
|
Blastomyces dermatitidis
|
|
|
Oral pottasium iodide is used as treatment in what organism?
|
Blastomyces dermatitidis
|
|
|
Which organism has diagnostic multiple budding yeast?
|
Paracoccides
|
|
|
Paracoccidiodes active infection more common in?
|
males
|
|
|
Which organism has diagnostic tuberculated chlamydospores at room temperature?
|
Histoplasma capsulatum
|
|
|
Which organisms yeast form is intracellular in phagocytes at 37C?
|
Histoplasma capsulatum
|
|
|
Infection w/ which organism is often confused as miliary TB?
|
Histoplasma capsulatum
|
|
|
Treatment of histoplasma?
|
Itraconazole
|
|
|
Other than PCP & Candida which other organism causes an "AIDS defining illness"?
|
Histoplasma
|
|
|
Which organism has endosporulating spherules in infected tissue?
|
Coccidodes
|
|
|
Which organism has arthrospores in culture?
|
Coccidiodes
|
|
|
Amphotericin B (IV) & Ketoconazole is used to treat which fungal infections?
|
1. Coccidiodes immitus
2. Candidiasis |
|
|
Which organism is typically involved in post-op infections resulting in wound dehiscense?
|
Aspergillus
|
|
|
Which organism is not thermodimorphic?
|
Candidia--> dimorphic but not dependent on temperature
|
|
|
If a patient presents with an infection which resembles oral thrush, how can you determine if that's what it is?
|
If it easily wipes off --> Oral thrush
|
|
|
What are predisposing factors for candida infection?
|
1. Broad spectrum antibiotics
2. Cortisone 3. Anesthesia |
|
|
Topical nystatin is used to treat?
|
Candida
|
|
|
Which fungus was once thought to be a protozoan?
|
Pneumocystiis carnii
|
|
|
Diagnosis of pneumocystis carnii is done by?
|
Silver stain
|
|
|
Bactrim is used to treat?
|
Pneumocystis carnii
|
|
|
Is pneumocystis carnii treated w/ amphotericin B or azoles?
|
NO-- lacks erosterol
|
|
|
How is cell wall of spirochetes dif from gram (-)?
|
Not rigid
|
|
|
Tight regular coils are present in?
|
Treponema
|
|
|
Coarse, irregular coils are present in?
|
Borrelia
|
|
|
Very tight coils w/ hooked ends are present in?
|
Leptospira
|
|
|
3 ways to visualize spirochetes?
|
1. Darkfield microscopy
2. Silver stain 3. Fluroscent antibody |
|
|
Yaws is caused by?
|
T. pertenue
|
|
|
Pinta is caused by?
|
T. carateum
|
|
|
T. denticola found in?
|
ANUG
|
|
|
Primary stage of syphyllis?
|
2-6 weeks
Chancre on genitals Painless & inconsicuous |
|
|
Secondary stage of syphillis?
|
2-6 weeks (week to months after primary)
-Non specific flu-like symptoms -Macular rash over trunk & limbs: Non-pruritic (doesn't itch) & symmetrical -Condylomata lata-- coalesced masses |
|
|
Latent syphilis?
|
Absence of signs & symptoms but (+) serology
|
|
|
Tertiary stage syphilis?
|
3-30 yrs after primary
-CV --> aortic lesions, heart failure -Neurosyphilis--> chronic meiningitis -Gummatous disease- granulomatous like lesions |
|
|
VDRL is used to test for?
|
Syphilis
|
|
|
Treatment of syphillis?
|
1. Penicillin
2. Doxycycline 3. Tetracycline 4. Chloramphenicol |
|
|
Relapsing fever is caused by?
|
Borellia recurrentis
|
|
|
Vector of B. recurrentis is?
|
body lice
|
|
|
Treatment of B. recurrentis is?
|
Tetracycline or erythromycin
|
|
|
Lyme disease is caused by?
|
Borrelia burgdorferi
|
|
|
Most common vector borne disease in US?
|
Lyme disease
|
|
|
Transmission of B. burgdorferi?
|
Tick bite
|
|
|
Eryhema migrans (target rash) is seen in?
|
Lyme disease (B. burgdorferi)
|
|
|
Borelia vincentii causes?
|
ANUG
|
|
|
Main cause of leptospirosis?
|
Leptospira interrogans
|
|
|
Major clinical manifestation of leptospirosis?
|
Jaundice
|
|
|
Bell's palsy like facial paralysis can be seen in?
|
Lyme disease
|
|
|
Most common serotype of leptospira interoggans in US is?
|
Canicola-- dog
|
|
|
Chemical agents w/ poor killing ability of viruses?
|
1. 70% alcohol
2. Cyanide & fluoride 3. Quarternary ammonia |
|
|
Chemical agents w/ good killing ability of viruses?
|
1. Detergents
2. Oxidizing agents 3. Heavy metal ions |
|
|
What do virally infected cells produce to protect other cells from infection?
|
IFN-gamma
|
|
|
Enteroviruses are stable at what pH?
|
pH 3-5
|
|
|
Anterior horn cells of spinal cord are affected by which organism?
|
Poliovirus
|
|
|
2 types of vaccines used for polio?
|
1. Salk-- killed
2. Sabin-- live-attenuated (Better) |
|
|
Picornaviruses have which type of genetic material?
|
(+) RNA
|
|
|
2-3 yr old child w/ sudden onset of fever, listlessness, loss of apatite, that is crying & miserable w/ red patches in oropharynx?
|
Herpangina
|
|
|
Coxsackie A virus causes?
|
Herpangina
|
|
|
How is herpangina (Coxsackie A virus) treated?
|
Tylenol or ibuprofen for fever & topical anesthetic for throat
|
|
|
Which viruses are more acid labile & heat stable than enteroviruses?
|
Rhinoviruses
|
|
|
Common cold (runny nose, couch, headache, chill) & usually afebrile (no fever) caused by?
|
Rhinoviruses
|
|
|
Genetic material of Herpesviruses?
|
DNA viruses
|
|
|
Most common human virus?
|
Herpesvirus
|
|
|
HSV-1:
-Age at primary infection? - Major site? |
HSV-1:
-Young children -Mouth |
|
|
HSV-2:
-Age at primary infection? -Major site? |
HSV-2:
-YOung adults -Genitalia |
|
|
Trigeminal ganglia is involved in?
|
HSV-1
|
|
|
Dorsal root ganglia is involved in?
|
HSV-2
|
|
|
Ballooning cells, intranuclear inclusion bodies & multinucleated giant cells are seen in?
|
HSV-1 & 2 pathogenesis
|
|
|
Whitlows infection is?
|
Herpes infection on fingers -- caused by contact w/ HSV-1 or HSV-2
|
|
|
Treatment of herpesvirus?
|
Acyclovir
|
|
|
Herpes virus 3?
|
Varicella-Zoster virus VZV
|
|
|
Varicella is?
|
Chickenpox
Mild, childhood disease w/ generalized rash & itchy w/ lil or no pain |
|
|
Zoster is?
|
Shingles:
Reoccurence of chickenpox in adults Unilateral rash w/ intense pain |
|
|
Ebstein-Barr Virus?
|
Herpesvirus-4:
-Infectious mono -Mutplies in: Epithelial cells (well) & B cells (poorly) -Burkitt's lymphoma |
|
|
Cytomegalovirus?
|
Herpesvirus-5:
-cell gigantism -Salivary gland enlargement |
|
|
Kaposi's sarcoma?
|
Herpesvirus-8:
-AIDS defining illness -Patches of red/purple lesions in mouth -Malignant |
|
|
Genetics of influenza virus?
|
(-) RNA
|
|
|
What is antigenic shift?
|
Major sudden antigenic changes
-GENETIC REASSORTMENT |
|
|
What is antigenic drift?
|
Minor antigenic changes
-POINT MUTATIONS |
|
|
hemagglutin & neuraminidase are important viral proteins in?
|
INfluenza virus
|
|
|
Function of Hemagglutinin?
|
ATTACHMENT
|
|
|
Function of Neuraminidase?
|
Release of virions from cell
|
|
|
Reyes syndrome is a result of which organism?
|
Influenza virus
|
|
|
How is avian flu transmitted?
|
From birds --> humans (not human to human)
-Antigenic shift-- bird flu genes integate into human flu genes |
|
|
Genetics of coronaviruses?
|
(+) RNA
|
|
|
Coronaviruses are limited to waht type of infections?
|
Upper respiratory tract
|
|
|
2 paramyxoviruses that produce acute respiratory diseases?
|
Parainfluenza virus & respiratory syncytial virus
|
|
|
Genetic material of paramyxoviruses?
|
(-) RNA
|
|
|
Which Ab does not prevent infection or disease from parainfleunza virus in infants?
|
Maternal IgG
|
|
|
Most important cause of lower respiratory tract illness in infants & young children?
|
Respiratory syncytial virus (RSV)
|
|
|
More serious symptoms of RSV infection may be explained by involvment of?
|
Immediate hypersensitivy reaction -- IgE
|
|
|
What is most important Ab involved in immunity from RSV?
|
IgA
|
|
|
Prodrome of malaise & anorexia, followed by rapid enlargement of parotid glands & secondary enlargment of testes or ovaries?
|
Mumps
|
|
|
Treatment of mumps?
|
Self-limiting
|
|
|
Primary growth of measles (rubeola) is in?
|
Lymphoid tissue & reticulo-endothelial system
|
|
|
INteraction of T cells & virally infected cells in blood vessels in Measles (rubeola) causes?
|
Rash
|
|
|
Prodromal fever, cold-like symptoms, red eyes, Koplik's spots on buccal mucosa & rash caused by?
|
Measles (Rubeola)
|
|
|
How is skin rash in measles different from chicken pox?
|
There is no blistering in measles
|
|
|
What is atypical measles?
|
Measles w/o rash
Typically seen in children who received killed measles vaccine |
|
|
Genetic material of togavirus?
|
(+) RNA
|
|
|
What type of virus is Rubella (german measles)?
|
Togavirus
|
|
|
Is rash seen in mumps, measles & rubella?
|
Mumps-- NO RASH
Measles-- Rash (atypical has no rash) Rubella- Rash |
|
|
What can possibly if women in 1st trimester of pregnancy get Rubella?
|
Possible fetus malformation
|
|
|
Which form of hepatitis can be transmitted by fecal-oral route?
|
Hepatitis A
|
|
|
Which forms of hepatitis have vaccines & can be cured?
|
Hep A & Hep B
|
|
|
Which form of hepatitis has the highest chronic carrier state & typically leads to hepatocellular carcinomas?
|
Hep C
|
|
|
What is important for measuring infectivity potential of Hep B?
|
HBeAg
Epsiolon antigen |
|
|
In order to get Hep D must have had previous infection w/?
|
Hep B
|
|
|
What type of virus is Hep A?
|
Picornavirus
|
|
|
Which Ab is found during early acute phase of Hep A?
|
IgM
|
|
|
Which Ab is found during acute phase of HepA?
|
IgM & IgG
|
|
|
Which Ab is found during recovering phase of Hep A or past infection?
|
IgG
|
|
|
Hep B is what type of virus?
|
DNA virus -- Hepadnavirus
|
|
|
What are the 3 possible clinical outcomes of Hep B infection?
|
1. Become resolved
2. Proceed to chronic infection 3. Fulminant hepatitis (sudden & severe) |
|
|
Chronic Hep B is ?
|
HBsAg positive for > 6 months
|
|
|
Which antigen is readily detected first in Hep B?
|
Surface Ag
|
|
|
What is the first Ab to appear in Hep B infection?
|
IgM
|
|
|
During Hep B infection which antigen persists the longest?
|
Core Ag
|
|
|
Hep C is what type of virus?
|
Flavivirus (RNA virus)
|
|
|
Reverse transcriptase is?
|
RNA-dependent-DNA polymerase
|
|
|
Why is HIV so difficult to treat?
|
-Integrates into host DNA
-Mutates rapidly |
|
|
In gram (-) bacteria what binds peptidoglycan layer to outer membrane?
|
Murein lipoprotein
|
|
|
6 classic gram (+) bacteria?
|
1. Strep
2. Staph 3. Bacillus 4. Clostridium 5. Corynebacterium 6. Listeria |
|
|
Which gram (-) bacteria is diplococci?
|
Neisseria
|
|
|
Which bacteria is neither gram (+) or (-)?
|
Mycoplasma - NO cell wall
|
|
|
Which 3 organisms are spirochetes?
|
1. Treponema
2. Borrelia 3. Leptospira |
|
|
Gram (+) Obligate aerobes? (2)
|
1. Nocardia (weak acid-fast)
2. Bacillus cereus |
|
|
Gram (-) Obligate aerobes? (5)
|
1. Neisseria
2. Pseudomonas 3. Boretella 4. Legionella 5. Brucella |
|
|
What are the O2 requirements of acid fast bacteria?
|
Mycobacterium & Nocardia
OBLIGATE AEROBES |
|
|
Gram (+) facultative anaerobes? (5)
|
1. Staph
2. B. anthracis 3. Corynebacterium 4. Listeria 5. Actinomyces |
|
|
Most gram (-) rods have what O2 requirements?
|
Facultative anaerobes
|
|
|
Which gram (+) bacteria is an obligate anaerobe?
|
Clostridium
|
|
|
Which gram (-) bacteria is an obligate anaerobe?
|
Bacteroides
|
|
|
Which gram (-) bacteria are microaerophilic (aerotolerant anaerobes)? (2)
|
1. Spirochetes
2. Campylobacter |
|
|
Bacteria that use fermentation & have no ETC but can tolerate low amounts of O2 because they have superoxide dimutase?
|
Microaerophilic or aerotolerant anaerobes
|
|
|
What are the 3 enzymes that all obligate aerobes & falcutative anaerobes contain?
|
1. Catalase
2. Peroxidase 3. Superoxide dismutase |
|
|
Facultative intracellular organisms? (7)
|
1. Listeria monocytogenes
2. Salmonella typhi 3. Yersinia 4. Fracisella tularenis 5. Brucella 6. Legionalla 7. Mycobacterium |
|
|
4 bacteria that produce enterotoxins which increase cAMP?
|
1. Cholera
2. Anthrax 3. Enterotoxigenic E. coli 4. Pertussis |
|
|
Major mechanism of transfer of antibiotic resistance genes?
|
Conjugation
|
|
|
Hfr cell?
|
When F plasmid is integrated into chromosome
-Can undergo conjugation & transfer entire chromosome or can transfer F plasmid w/ some chromosomal DNA |
|
|
How is F' plasmid formed?
|
-Hfr cell (F plasmid integrated into chromosome) undergoes abnormal exision
-Chromosomal DNA has been integrated into F plasmid -Conjugation occurs & F- cell gets F plasmid w/ chromsomal DNA |
|
|
F' conjugation is analagous to?
|
Specialized transduction
-Nearby segment of chromosomal DNA is accidentally transfferred to other bacterial cells |
|
|
2 antigenic components of strep group A cell wall?
|
1. C carbohydrate (identifies group A strep)
2. M protein |
|
|
Major virulence factor of group A strep?
|
M protein
-Inhibits activation of complement & phagocytosis -But Ab from B cells can bind M protein (oposonization) & destroy |
|
|
3 most common pathogens associated w/ neonatal meningitis?
|
1. Strep agalactaiae (group B)
2. E. coli 3. Listeria monocytogenes |
|
|
Group D strep?
|
Enterococci: E. faecalis & E. faecium
Non-enterococci: S. bovis & S. equinus |
|
|
Most common cause of pneumonia in adults?
|
S. pneumonia
|
|
|
3 Most common causes of ottis media (Middle ear infection) in kids?
|
1. S. pneumoniae
2. H. influenzae 3. Moraxella catarrhalis |
|
|
Most common cause of bacterial meningitis in adults?
|
S. pneumoniae
|
|
|
What can be used to differentiate between alpha-hemolytic strep?
|
Viridans- optochin resistant
S. pneumoniae- optochin sensitive |
|
|
3 forms of anthrax?
|
1. Cutaneous anthrax
2. Respiratory anthrax 3. GI anthrax |
|
|
Mechanism of B. anthracis exotoxins? (3)
Encoded on pXO1 plasmid |
1. EF- Increases cAMP-impairs neutrophils & increases edema
2. PA-promote entry of EF 3. LF-zince metalloprotease that inactivates protein kinase--> TNF & IL-1 |
|
|
What enterotoxins are responsible for causing food poisoning due to B. cereus?
|
1. Heat labile toxin- similar to cholera & LT of E. coli (Diarrhea)
2. Heat stable toxin- similar to S. aureus food poisoning (N/V) |
|
|
Trismus, lockjaw & Risus sardonicus are seen due to which toxin?
|
Tetanospasm - C. tetani
|
|
|
Gray pseudomembrane of pharynx of child is due to which bacteria?
|
Corynebacterium Diphtheriae
|
|
|
Which bacteria is pleomorphic & often looks like chinese characters?
|
C. diphtheriae
|
|
|
2 bacteria that cause meningitis after maternal Ab given to fetus are gone & before new Ab develop?
|
1. Neisseria meningitidis
2. H. influenzae |
|
|
Classic sign to an invasive meningococcal infection is?
|
Petechial rash
|
|
|
Septick shock with bilateral hemorrhage into adrenal glands that causes adrenal insurfficiency, hypotension, tachycardia & rapidly enlarging petechial skin lesions
|
Waterhouse-Friderischen syndrome (fulminant meningococcemia)
|
|
|
Which enterics do NOT ferment lactose? (3)
|
1. Salmonella
2. Shigella 3. Psedomonas |
|
|
What is the mechanism of the Shigatoxin & Verotoxin of EHEC?
|
Both INHIBIT PROTEIN SYNTHESIS
-Inhibit 60S ribosome --> intestinal cell death |
|
|
Most common cause of gram (-) sepsis?
|
E. coli
|
|
|
Which bacteria has cross-reacting Ag w/ Rickettsia & can be used to determine if a person is infected w/ Rickettsia
|
Proteus
(OX-19, OX-2, OX-K) |
|
|
Which enterics are NEVER found as normal flora in humans? (2)
|
1. Shigella
2. Salmonella |
|
|
Salmonella is encapsulated by?
|
Vi capsule
|
|
|
Pt's w/ sickle cell anemia are particularly prone to osteomyelitis infection by which bacteria?
|
Salmonella
|
|
|
Pathogenesis of Y. entercolitica?
|
1. Invasion (like salmonella, shigella, EIEC, C. jejuni)
2. Entertoxin (like heat stable toxin of E. coli) |
|
|
Which enterics do NOT invade cells?
|
1. ETEC
2. V. cholerae |
|
|
What bacteria looks like V. cholera- comma shaped w/ single polar flagellum?
|
Campylobacter jejuni
|
|
|
3 most common causes of diarrhea in the world?
|
1. C. jejuni
2. ETEC 3. ROtavirus |
|
|
Common causes of right heart valve endocarditis in IV drug users? (2)
|
S. aureus
Pseudomonas |
|
|
Gram (-) rods acquired through respiratory tract? (3)
|
1. Haemophilus
2. Bordetella 3. Legionella |
|
|
Most serious infection caused by encapsulated Haemophilus influenzae type b?
|
Meningitis in infants (6 mon-3 yrs)
-Used to be most common cause of meningitis in infants but now there is vaccine & N. meningitides is most common |
|
|
Most common cause of septic arthritis in infants?
|
Haemophilus infleunzae type B
|
|
|
Legionella pneumophilia is found where?
|
Contaminated aerosilized water
|
|
|
Which bacteria is a facultative intracellular parasite for free living ameobas?
|
Legionella pneumophilia
|
|
|
2 gram (-) obligate intracellular bacteria?
|
1. Chlamydia
2. Rickettsia (unable to make their own ATP) |
|
|
Which gram (-) bacteria has no peptidoglycan layer & no muramic acid?
|
Chlamydia
|
|
|
What are the major differences between Coxiella burnetti (Q fever) & Rickettsia? (4)
|
1. Endospores- resistant to heat & drying
2. Extracellular existance 3. Non-arthropod transmission 4. Pneumonia |
|
|
What types of epithelium do Claymidia & Rickettsia?
|
Chlamydia- columnar epithelium
Rickettsia- endothelium |
