Step 1 - Micro Bug list 2

denniskwinn's version from 2015-04-25 16:07


Question Answer
Klebsiella pneumoniae disease featuresPneumonia, especially in Alcoholics and poor lung function and diabetics), UTI (in catheterized patients), Bacteremia
Klebsiella pneumoniae identificationGm - rod, oxidase - mucoid appearing colonies in culture
Klebsiella pneumoniae pathogenic factorslarge antiphagocytic capsule
Klebsiella pneumoniae transmissionaspiration of respiratory droplets
Klebsiella pneumoniae prevention/treatmentcephalosporins, BL-BLI
Legionella pneumophila disease featuresLegionnaires disease, Pontiac fever
Legionella pneumophila identificationGm - coccobacillus, silver stain, facultative intracellular, BCYE agar (need iron and cysteine), urine antigen
Legionella pneumophila pathogenic factorsGrowth in macrophages, degradative enzymes kill parasitized cells
Legionella pneumophila transmissionAerosols from contaminated water sources (no person to person spread)
Legionella pneumophila prevention/treatmentChlorination of water sources, Erythromycin, new macrolides, fluoroquinolone


Question Answer
Neisseria gonorrhoeae disease featuresUrethral or vaginal discharge, PID and salpingitis, Septic arthritis, Neonatal conjunctivitis, dermatitis-arthritis syndrome
Neisseria gonorrhoeae identificationGm - cocci, no capsule, ferments glucose, growth on thayer-martin or chocolate agar
Neisseria gonorrhoeae pathogenic factorsPili, strong endotoxin effect, protein I(intracellular survival), Protein II (adhesin), IgA protease; B-lactamas
Neisseria gonorrhoeae transmissionSexual contact; during birth from infected mother
Neisseria gonorrhoeae prevention/treatmentCondoms, prophylaxis with silver nitrate or erythromycin for neonates, ceftriaxone+antichlamydial drugs
Neisseria meningitidis disease featuresMeningitis, Meningococcemia (generalized petechial/purpura rash, septicemia
Neisseria meningitidis identificationGm - cocci, glucose and maltose fermenter, growth on thayer martein or chocolate agar, High protein and low glucose in CSF
Neisseria meningitidis pathogenic factors Antiphagocytc capsule, strong endotoxin effect
Neisseria meningitidis transmissionRespiratory droplets
Neisseria meningitidis prevention/treatmentAnticapsular vaccine, penicillin, chloramphenicol, ceftriaxone, fluoroquinolones for contacts


Question Answer
Proteus mirabilis disease featuresUTI often with renal stone formatoin
Proteus mirabilis identificationGm - rod, swarming growth on agar, Urease +, oxidase -, lactose -
Proteus mirabilis pathogenic factorsIncreased urine pH due to urease activity promotes renal stone and is toxic to uroepithelium
Proteus mirabilis transmissionendogenous spread of normal GI tract flora
Proteus mirabilis prevention/treatmentAmpicillin, TMP-SMX, Cephalosporins


Question Answer
Pseudomonas aeruginosa disease featuresNosocomial infections, Burn infections w/bacteremia, UTI(catheters), Pulmonary infections (CF), Keratitis (swimmer’s ear, Hot-tub folliculitis), Malignant external otitis in diabetics
Pseudomonas aeruginosa identificationGm - rods, motile, oxidase +, flat colonies, fruity odor, blue-green pigment
Pseudomonas aeruginosa pathogenic factorsPili; capule; A-B type exotoxin inhibits protein synthesis by ribosylation of EF-2, leukocidin; degradative enzymes
Pseudomonas aeruginosa transmissionubiquitous in environment and water, nosocomial spread via water resevoirs
Pseudomonas aeruginosa prevention/treatmentFluoroquinolones, ceftazidime, polymyxin, aztreonam, aminoglycosides, special beta lactams
Salmonella enteritidis disease features gastroenteritis with vomiting, diarrhea, nonbloody diarrhea
Salmonella enteritidis identificationGm - rod, oxidase -. Lactose - , colonies w/black center (hydrogen sulfide) on SS agar
Salmonella enteritidis pathogenic factorsAntiphagocytic capsule, exotoxin, intracellular growth
Salmonella enteritidis transmissionFecal-oral via water or food (raw eggs, poultry, dairy products)
Salmonella enteritidis prevention/treatmentRehydration, no antibiotics used
Salmonella typhi disease featuresTyphoid fever, increasing fever, necrosis and hemorrhage of GI tract, bacteremia
Salmonella typhi identificationGm - rod, motile, oxidase - , lactose - ,
Salmonella typhi pathogenic factorsantiphagocytic capsule, invasion of peyer’s patches
Salmonella typhi transmissionfecal oral via water or food
Salmonella typhi prevention/treatmentChloramphenicol, cephalosporins, quinolones
Shigella spp disease featuresShigellosis (bacterial dysentary), fever, cramps, tenesmus, and blood stools,...S. Sonnei is milde disease (day care centers).. S. Flexneri and s.dysentariae (more severe, less common)
Shigella spp identificationGm - rod, oxidase -. Lactose - No H2S on SS agar
Shigella spp pathogenic factorsInvades and replicats within colonic mucosa; A-B type exotoxin (shiga toxin) that inhibits 28s rRNA (s. Dysentariae)
Shigella spp transmissionFecal-oral usualy via hands
Shigella spp prevention/treatmentRehydration in mild cases , ampicillin in severe cases
Vibrio cholerae disease featuresrice-water stools, profuse water diarrhea
Vibrio cholerae identificationgm - comma shaped rod, motile, salt tolerant, oxidase+
Vibrio cholerae pathogenic factorsAdherence to gut mucose, A-B type exotoxin increase cAMP by stimulating “on” G protein - loss of water and ions from cells.
Vibrio cholerae transmissionFecal - oral via water, fish and shellfish, shedding from asx carriers
Vibrio cholerae prevention/treatmentRehydration, tetracycline, electrolyte replacement
Vibrio parahaemolyticus disease featuresGastroenteritis with explosive, watery diarrhea, cramps, nausea
Vibrio parahaemolyticus identificationSame as V. cholerae
Vibrio parahaemolyticus pathogenic factorsInvasion and destruction of colonic epithelium
Vibrio parahaemolyticus transmissionIngestion of contaminated shellfish
Vibrio parahaemolyticus prevention/treatmentUsually self limited
Yersinia enterocolitica disease featuresEnterocolitis with blood diarrhea, fever, abd pain
Yersinia enterocolitica identificationGm - rod, motile, oxidase - , lactose -, cold tolerant
Yersinia enterocolitica pathogenic factorsAntiphagocytic capsule, intracellular growth; endotoxin, cold tolerant
Yersinia enterocolitica transmissionZoonotic via contaminated food, water or blood products
Yersinia enterocolitica prevention/treatmentAminoglycosides, TMP-SMX
Yersinia pestis disease featuresBubonic plague, high fever, painful buboes, conjunctivitis
Yersinia pestis identificationGm - rod, oxidase - , lactose -
Yersinia pestis pathogenic factorsantiphagocytic capsule, intracellular growth, exotoxin, fibrinolysin
Yersinia pestis transmissionZoonotic via flea vectors
Yersinia pestis prevention/treatmentKilled vaccine, streptomycin, chloramphenicol


Question Answer
Borrelia burgdorferi disease featuresrash (erythema chronicum migrans), severe fatigue, involvement of heart, CNS and joints
Borrelia burgdorferi identificationLarge spirochetes, microaerophilic, numerous flagella, serologic tests for antibodies
Borrelia burgdorferi pathogenic factorsInduced cell-mediated and inflammatory responses, weak endotoxin effect
Borrelia burgdorferi transmissionZoonotic via ticks (Ixodes spp); NE, upper Midwest and pacific NW
Borrelia burgdorferi prevention/treatmentDoxycycline and amoxicillin (early), Ceftriaxone (late)
Chlamydophila pneumoniae disease featuresAtypical pneumoniae, children and young adults at greatest risk; association with coronary artery disease
Chlamydophila pneumoniae identificationObligate intracellular, no peptidoglycan in cell wall
Chlamydophila pneumoniae pathogenic factorsSimilar to C. trachomatis
Chlamydophila pneumoniae transmissionrespiratory droplets
Chlamydophila pneumoniae prevention/treatmentTetracycline, erythromycin, new marcolides, fluoroquinolones (resp)
Chlamydophila psittaci disease featuresParrot fever: dry cough, pneumonitis, splenomegaly, CNS involvement
Chlamydophila psittaci identificationObligate intracellular, no peptidoglycan in cell wall
Chlamydophila psittaci pathogenic factorsExtracellular inert form (elementary body) enters target cells; active form (reticulate body) replicates within cells leading to cell lysis and host inflammatory process
Chlamydophila psittaci transmissionAerosols from dried bird poo
Chlamydophila psittaci prevention/treatmentTetracycline, erythromycin, new marcolides, fluoroquinolones (resp)
Chlamydophila trachomatis disease featuresA-Ctrachoma (conjunctivitis) leading to blindness if untreated, D-K: urogenital, neonatal conjunctivitis, L1-L3Lymphogranuloma venereum (buboes)
Chlamydophila trachomatis identificationObligate intracellular, no peptidoglycan in cell wall, iodine-staining inclusion body, serologic test
Chlamydophila trachomatis pathogenic factorsExtracellular inert form (elementary body) enters target cells; active form (reticulate body) replicates within cells leading to cell lysis and host inflammatory process
Chlamydophila trachomatis transmissionsexual contact or via birth canal; contact with tears
Chlamydophila trachomatis prevention/treatmentTetracycline, erythromycin, new marcolides, fluoroquinolones (resp)
Coxiella burnetii disease featuresQ fever - usual sx of ricketsial disease but no rash, Atypical pneumonia, endocarditis, liver involvement
Coxiella burnetii identificationObligate intracellular
Coxiella burnetii pathogenic factorsunknown
Coxiella burnetii transmissionaerosols of urine or feces and contact with birth products from infected animals
Coxiella burnetii prevention/treatmentTetracycline
Mycobacterium leprae disease featuresTuberculoid leprosy: few skin lesions with few bacilli, Lepramatous leprosy: numerous skin lesions with many bacilli, tissue damage, loss of sensation
Mycobacterium leprae identificationAcid-fast rod; obligate intracellular - positive lepromin skin tests, infects cool tissues
Mycobacterium leprae pathogenic factorsCell wall phenolic glycolipis, host TH1 response leads to tuberculoid form, TH2 response leads to lepromatous form
Mycobacterium leprae transmissionDirect contact with lesions, inhalation of infectious droplets
Mycobacterium leprae prevention/treatmentTuberculoid with dapsone+rifampin (6mo) Lepromatous with dapsone+rifampin+clofazimine for 2 years
Mycobacterium tuberculosis disease featuresTB - Young kids, elderly and immunocompromised at greatest risk
Mycobacterium tuberculosis identificationAcid fast rod; facultative intracellular, slow groth on Lowenstein-Jensen medium, +PPD skin test, IFN gamm tests
Mycobacterium tuberculosis pathogenic factorsCord factor, mycolic acid, intracellular growth, granuloma formation and caseation due to induced DTH response
Mycobacterium tuberculosis transmissionResp droplet from infected person
Mycobacterium tuberculosis prevention/treatmentProphylactic isoniazid, BCG vaccine, Multidrug therapy for 6-9 months
Mycobacterium avium-intracellulare complex (MAC) disease featuresDisseminated infections of AIDS and other immunocompromised
Mycobacterium avium-intracellulare complex (MAC) identification Acid fast rod; facultative intracellular, slow groth on Lowenstein-Jensen medium,
Mycobacterium avium-intracellulare complex (MAC) pathogenic factorssimilar to TB but more of an opportunistic infection
Mycobacterium avium-intracellulare complex (MAC) transmissionResp droplets
Mycobacterium avium-intracellulare complex (MAC) prevention/treatmentAzithromycin or clarithromycin+ethambutol+rifabutin NOT Isoniazid
Mycoplasma pneumoniae disease featuresAtypical walking pneumonia, Pharyngitis, tracheobronchitis
Mycoplasma pneumoniae identificationNo cell wall, sterols in cell membrane, obligate aerobe, granular colonies on eaton agar
Mycoplasma pneumoniae pathogenic factorsAdherence to resp epithelium, damage to epithelium due to H2O and lytic enzymes
Mycoplasma pneumoniae transmissionresp droplets
Mycoplasma pneumoniae prevention/treatmentErythromycin, Tetracycline, quinolones
Nocardia spp disease featuresCutaneous infections (mycetoma), Pneumo w/cavitation and spread to CNS or skin in immunocompromised
Nocardia spp identificationAcid fast (weakly). Filamentous aerobic
Nocardia spp pathogenic factorscolonization of oropharynx or wounds subsequent necrosis and abscess formation
Nocardia spp transmissionUbiquitous soil organisms, inhaled and aspirated to lower airways or enter via wounds
Nocardia spp prevention/treatmentsulfonamides, surgical intervention
Rickettsia spp prevention/treatmentTetracycline, Chloramphenicol
Rickettsia spp disease featuresRock mountain spotted fever (rickettsii) = inward spreading rash, Endemic typhus (typhi) = rash on trunk, Epidemic typhus (prowasekii) = outward spreading rash
Rickettsia spp identificationobligate intracellular weil-felix reaction to distinguish rickettsial species; serology
Rickettsia spp pathogenic factorsInvasion and destruction of endothelial cells
Rickettsia spp transmissionrickettsii = deer tick vector, typhi = flea vector, prowazecki = person to person via body lice
Treponema pallidum disease features Primary = painless skin ulcer, buboes, Secondary = flu-like syndrome, disseminated rash, Tertiary = gummase, aortitis, CNS involvement, Congenital = unusual teeth, deafness, interstitial keratitis, saber shins
Treponema pallidum identificationThin spirochetes visualized by dark field microscopy, VDRL or RPR tests, FTA-ABS tests for treponemal antibodies
Treponema pallidum pathogenic factorsHyaluronidase (tissue invasion); protective outer coat, induced host response
Treponema pallidum transmissionSexual contact, transplacental transfusion with contaminated blood
Treponema pallidum prevention/treatmentPenicillin