IAHI Block 2 Bacteria Flashcards
Staphylococcus aureus
Gram: Positive
Geometry: Coccus, clusters
Pathology: protein A, beta hemolysins, leukotoxins, enterotoxins, proteases
Culture: catalase positive, coagulase positive, beta hemolysis
Disease: scalded skin syndrome, impetigo, pneumonia
Exposure: normal flora of nares
Treatment: penicillin < methicillin < vancomycinr
Staphylococcus epidermis
Gram: positive Geometry: coccus, clusters Pathology: binds to plastics Culture: catalase positive, coagulase negative Disease: infection Exposure: hospital acquired infection
Staphylococcus saprophyticus
Gram: positive
Geometry: coccus, clusters
Pathology: binds to urinary tract endothelial cells
Culture: catalase positive, coagulase negative
Disease: UTI
Exposure: typically sex-related UTI
Streptococcus pyogenes
Gram: positive
Geometry: coccus, chains
Pathology: M proteins, hyaluronic acid capsule, Spe toxins, streptolysins S & O, streptokinase (plasmin activator)
Culture: catalase negative, beta hemolysis
Disease: rheumatic fever, scarlet fever, necrotizing fasciatis, strep throat
Exposure: droplet transmission
Treatment: penicillin, penicillin +clindamycin for systemic infections
Streptococcus agalactiae
Gram: positive
Geometry: coccus, chains
Pathology: group B capsule; mostly asymptotic in adults
Culture: PCR, antigen test
Disease: neonatal disease
Exposure: congenital
Treatment: penicillin, penicillin + aminoglycoside for systemic infections
Streptococcus pneumonia
Gram: positive
Geometry: coccus, pairs
Pathology: IgA protease; pneumolysin; teichoic acid, C polysaccharide, F antigen capsule (inflame and migrate)
Culture: catalase negative, alpha hemolysis
Disease: pneumonia, meningitis, otitis media
Exposure:
Treatment: Vaccine; vancomycin and ceftriazone for sever infectionsy
Listeria monocytogenes
Gram: positive
Geometry: bacillus, 1 polar flagellum
Pathology: Listeriolysin O, ActA, Internalin
Culture: catalase positive, oxidase negative, beta hemolysis, grow in cold, high salt
Disease: listeriolysis
Exposure: intoxication, soft cheese
Neisseria meningitidis
Gram: negative Geometry: diplococci Pathology: LPS, capsule (sialic acid), pili, porins A and B, host transferrin Culture: oxidase positive Disease: meningitis, petichiae Exposure: Treatment: vaccine; ceftriaxone
Neisseria gonorrhea
Gram: negative
Geometry: diplococci
Pathology: pili for attachment, porB resists granulocytes, opa proteins for binding
Culture: oxidase positive, requires complex medium
Disease: Gonorrhea
Exposure: sexual contact
Chlamydia trachomatis
Gram: negative
Geometry: coccobacilli,
Pathology: lipopolysaccharides, no peptidoglycan, two forms (elementary body, reticulate body)
Culture: obligate intracellular,
Disease: chlamydia, trachoma (keratoconjunctivitis)
Exposure: sexual contact; contact with infectious material
Clostridium dificile
Gram: positive Geometry: bacillus, spores Pathology: enterotoxin Culture: anerobic, PCR Disease: gastroenteritis Exposure: colonic flora, antibiotic treatment; fecal-oral Treatment: vancomycin, fecal transplant
Salmonella typhi
Gram: negative
Geometry: rods, flagellum
Pathology: specious vacuole, pathogenicity islands I and II, macrophage infection
Culture: lactose negative, H2S positive
Disease: typhoid fever, gastroenteritis
Exposure: food, carrier; low infectious dose
Treatment: vaccine; fluids, ciprofloxacin for systemic infections
Salmonella non-typhi
Gram: negative Geometry: rods, flagellum Pathology: specious vacuole, pathogenicity islands I and II Culture: lactose negative, H2S positive Disease: gastroenteritis Exposure: food, high infectious dose Treatment: fluids
Shigella dysenteraie
Gram: negative
Geometry: rod
Pathology: type III secretions, shiga toxin (cleaves 28S ribosomal RNA), IpA, actin polymerizers
Culture: lactose negative
Disease: dysentery
Exposure: fecal-oral; low infectious dose
Treatment: ceftriaxone, ampicillin for severe infections
enterohemorrhagic E. coli
Gram: negative
Geometry: Rod
Pathology: type III secretions, shiga toxins 1 and 2, Tir
Culture: sorbitol negative
Disease: gastroenteritis
Exposure: food, fecal-oral; low infectious dose
Campylobacter
Gram: negative Geometry: spiral, polar flagellum Pathology: LPS Culture: oxidase positive, microaerophilic, warm incubation Disease: gastroenteritis Exposure: chicken Treatment: Electrolytes
Helicobacter
Gram: negative
Geometry: spirochete, many polar flagellum
Pathology: Urease, CagA, VacA, Tir
Culture: microaerophilic, gastic biopsy,
Disease: peptic ulcers
Exposure: fecal-oral
Treatment: PPI, a macrolide, and a beta-lactam
Vibrio cholerae
Gram: negative
Geometry: comma, polar flagellum
Pathology: cholera toxin, Zot, Ace (GM1 binders); toxin coregulated pilus (TCP)
Culture: oxidase positive, requires NaCl
Disease: cholera
Exposure: infected water, high infection dose
Treatment: vaccine; electrolytes, ciprofloxacin,
Anaplasma
Gram: negative
Geometry: bacillus, TINY
Pathology: replicates in vacuoles, early pathway in neutrophils
Culture: blood smear, PCR
Disease: Anaplasmosis
Exposure: Ixodes scapularis and Ixodes pacificus
Treatment: doxycycline
Ehrlichia
Gram: negative
Geometry: bacillus, TINY
Pathology: replicates in vacuoles, early pathway in monocytes
Culture: blood smear, PCR
Disease: Erlichiosis
Exposure: A. americanum and Ixodes scapularis
Treatment: doxycycline
Rickettsia
Gram: negative
Geometry: bacillus
Pathology: replicates in cytoplasm; LPS, peptidoglycan, type IV secretion
Culture: N/A
Disease: Rocky Mountain Spotted Fever
Exposure: Dermacentor variabilis and dermacentor andersoni
Treatment: doxycycline, chloramphenicol if pregnant or mild disease
small rodent disease, humans are incidental host
Borrelia Burgdorfieri
Gram: negative
Geometry: spirochetes, flagella under outer membrane
Pathology: replicates outside cells in blood
Culture: dark microscopy
Disease: Lyme disease
Exposure: Ixodes scapularis and Ixodes pacificus
Treatment: doxycycline, ceftriaxone if CNS involvement
Treponema pallidium
Gram: negative
Geometry: spiral,
Pathology: Primary:chancre; secondary: condyloma latum; teritary: gumma, neurosyphilus
Culture: anti-cardiolipin (quick, non-specific) and fluorescent antibody test (specific); dark field microscopy of lesion
Disease: syphilus
Exposure: sexual contact with chancre, contact with condyloma latum, congenital
Treatment: long acting penicillin
Mycoplasma
Gram: No cell wall Geometry: Pathology: Culture: Disease: Exposure:
Mycobacterium leprae
Gram: Lipid rich cell wall
Geometry: rods
Pathology: tuberculoidal form attacks nerves, lepromatous forms large plaques
Culture: can only be cultured in nude mice or armidillos
Disease: lepramatous leprosy, tuberculoidal leprosy
Exposure: armidillos, inhalation
Treatment:
Mycobacterium tuberculosis
Gram: Lipid rich cell wall, mycolic acids
Geometry: rods
Pathology: fluid in lungs, malaise
Culture: acid fast staining; PPD skin test; cord factor granulomas (potato chips) growth
Disease: Tuberculosis
Exposure: close contact, inhalation
Treatment: isoniazid, rifampicin, ethambutol, pyrazinamide for 2 months, and 4 more months of isoniazid, rifampicin
legionella
Gram: negative
Geometry: rod, 1 polar flagella
Pathology: infects macrophages, IV secretion system, endotoxins lipases
Culture: grows slowly and only on buffered charcoal yeast media; fluorsecent antibody microscopy; oxidase positive, catalase negative; requires L cysteine, ferric iron
Disease: legionaire’s disase, Pontaic fever
Exposure: infected water; immunocompromised
Treatment: water chlorination, super heating; antibiotics for legionaire’s
Bordetella pertussis
Gram: negative Geometry: bacillicocci Pathology: catarrhal: mild URI; paroxysmal: whooping cough; convalescence: coughing persists Culture: strict aerobe, Disease: whooping cough Exposure: aerosol droplets Treatment: vaccine
Pseudomonas
Gram: negative
Geometry: bacillus, polar flagellum
Pathology: alginate coat (biofilm); endotoxin, exotoxin, pyo-substances (oxidative release), elastase and alkaline phosphatase
Culture: bright green colonies, beta hemolytic; glucose, xylose, fructose, and galactose postive
Disease: infection
Exposure: biofilm forms on plastics, exposure to wound
Treatment: widely resistant, combinations
Haemophilus influenzae
Gram: negative
Geometry: coccobacillary
Pathology: ribose and ribitol polysaccharide capsule
Culture: catalase positive, oxidase postive
Disease: influenzae associated meningitis
Exposure: Nasopharynx
Treatment: Hib vaccine
