Chapter 18-21 Flashcards

Question

Hemolytic Classification of Strep: Alpha hemolytic Streptococci

Answer 1

- incomplete breakdown of hemoglobin - results in green ring around colonies - S. pneumoniae

Answer 2

- spiky cell wall surface projections contribute to virulence by resisting phagocytosis and improving adherence; heat, acid resistant. - 80 different subtypes exist

Answer 3

- Streptococcal pharyngitis - Pneumonia - Pneumococcal meningitis - Dental Caries - Non newborn impetigo - Scarlet fever - Erysipelas - Necrotizing fasciitis - Cellulitis - Neonatal sepsis - Puerperal fever - Bacterial endocarditis

Answer 4

- Initial GAS (streptococcus pyogenes) infection may lead to sequelae that appear weeks later. Pathology due to response of bodys immune system to strep antigens - Rheumatic Fever (RF) - Autoimmune complication - 10% Sydenhams chorea (neurological disorder of childhood) - acute Glomerulonephritis (inflammation of kidney)

Answer 5

- Gastrointestinal tract, vagina, oral cavity - opportunistic pathogen; nosocomial infections - hardy, persists as contaminants in hospital environment, on hands, beds, as fecal aerosol - responsible for infections of surgical wounds, UTI's, Septicemia from indwelling catheters - now resistant to most antibiotics - VRE (Vancomycin resistant enzyme)

Answer 6

-N. meningitidis (meningococcus) -N. gonorrhoeae (gonococcus) -Factors contributing to pathogenicity >multiple fimbriae >protease cleaves secretory antibody (IgA) on mucosa -Treatment: >currently, many isolates resistant to penicillin >often occurs as co infection with other STD >multi-drug treatment: eg a cephalosporin + tetracycline

Answer 7

- have receptors for human mucus membranes - found in mucosal cells of genitourinary tract, eye, rectum, and throat - besides role in attachment, fimbriae slow phagocytosis by macrophages and neutrophils

Answer 8

- facultative anaerobe | - B. anthracis, B. cereus, B. Subtilis

Answer 9

- obligate anaerobe - C. tetani (cause tetanus; not treatable but preventable with tetanus shot; produces exotoxin Tetanospasmin) - C. botulinum (exotoxin, neurotoxin, blocks contraction, flasid (relaxation/weak)) - C. difficile (effect G.I. tract, diarrhea; Treatment: fecal transplant)

Answer 10

alpha toxin - RBC rupture - Edema - Tissue destruction

Answer 11

Tetanospasmin: Spastic Paralysis

Answer 12

- irregular: (pleomorphic; stain unevenly) - club shaped; snapping binary fission (V); palisades (line in a row next to each other) - leather like sheath forms in throat (local infection); toxin invades organs (toxemia); prophage has toxin genes; cutaneous infection emerging; DTaP (toxoid); DAT (antitoxin)

Answer 13

- irregular: (pleomorphic; stain unevenly) - cause acne - metabolizes sebum

Answer 14

- Regular: (stain uniformly; no pleomorphic shapes) - Psychrophile; not fastidious; resistant to cold, heat, salt, pH extremes and bile - An intracellular pathogen for a part of its life cycle; induces its own phagocytosis, replicates in host cell; moves from cell to cell to avoid immune defense; primary reservoir: food + water; secondary: animals; Listeriosis #2 in food fatality

Answer 15

L. acidophilus

Answer 16

- gram variable - normally inhabits vagina at pH 3.8; at high pHs interacts with anaerobic bacteria to cause vaginitis - symptoms: "clue cells" and fishy odor

Answer 17

- Mycobacterium spp. - M. tuberculosis, M. leprae, M. bovis, M. avium-intracellulare (mai) - aerobic, non-endospore former - no capsules, no flagella - usually contains granules and vacuoles - slow grower; (2 hours to several days) - acid fast: distinctive cell wall resembles gram (-) but LPS replaced mycolic acid which forms a waxy, water resistant layer - drug resistant - MDR strains emerging

Answer 18

- wax (resists desiccation; mycolic acid which forms a waxy, water resistant layer; replaces LPS on cell wall) - cord factor (prevent digestion by macrophage lysosomes, cord formation in infected tissue) - massed filaments stain red-acid fast

Answer 19

- inhaled bacilli (fine droplets of respiratory mucus suspended in air) - dried phlegm (bacilli may survive 8 months)

Answer 20

INH + Rifampin

Answer 21

- opportunistic infection - host susceptibility affected by presence of other illness (i.e. HIV) - debilitation of the immune system - inadequate nutrition or malnutrition - overcrowding - poor access to medical care - lung damage - stress - genetics

Answer 22

- initial contact - infection - latency (bacilli go dormant in lungs; carrier state without symptoms may last for many years; TB test (+) - Disease (tuberculosis)

Answer 23

- Leprosy or Hansen's Disease - Transmitted by contact with exudates (a mass of cells and fluid that has seeped out of blood vessels or an organ) - Treatment: rifampin + dapsone + clofazimine - mild; no longer fatal (with treatment) - Lepromin test - If effective cellular immunity, skin discoloration (tuberculoid form) - If ineffective, disfiguring nodules and tissue necrosis (rotting) (progressive or lepromatous form)

Answer 24

- zoonosis - "undulating fever" (105 Degrees F) - B. abortus (affects cows) - B. suis (affects pigs) - B. melitensis (affects goats) - B. rangiferi

Answer 25

- causes whooping cough or Pertussis - acute respiratory syndrome in babies; may be mild in adults - Transmission: direct contact with inhaled respiratory droplets given off during coughing state of infection - Virulence Factors: adhesion molecules bind specifically to ciliated respiratory cells; toxins destroy and dislodge ciliated cells - Stages: catarrhal (coughing), paroxymal (seizure part) - acellular vaccine (aP) - Treatment: azithromycin (1 week)

Answer 26

the severity or harmfulness of a disease or poison

Answer 27

(whooping cough or pertussis) | direct contact with inhaled respiratory droplets given of during coughing stage of infection

Answer 28

adhesion molecules bind specifically to ciliated respiratory cells; toxins destroy + dislodge ciliated cells

Answer 29

azithromycin (1 week)

Answer 30

- opportunistic pathogen - Otitis externa (swimmers ear); respiratory infections; burn infections - Pyocyanin (blue green pus) - actively grows in (QUATS)

Answer 31

- Tularemia; zoonotic disease; associated with rabbits - Transmitted by contact, ingestion, bite, vector, inhalation - Extremely infectious: infective dose 10 to 50 organisms - Intracellular pathogen; spreads within macrophages - Pulmonary form 10% mortality rate - Treatment: Gentamycin, docycycline

Answer 32

- Legionellosis - prefers charcoal yeast agar - motile; no capsule - Transmitted through a/c cooling towers, warm water supply lines, air ducts, spas, tap water, supermarket misting vegetable sprayers, decorative fountains - Mortality rate: 3% to 30% - Treatment: erythromycin alone or in combination with rifampin - Control: Chlorination

Answer 33

- Greek name for "motionless" - pleomorphic; resembles H. influenzae - enters body through open wounds, catheters, breathing tubes - usually infects immune compromised; opportunistic - colonization no threat to non compromised people, but colonized health care workers and hospital visitors carry + transmit bacteria - frequently causes nosocomial infections - aka "Iraqibacter" (spread via widespread contamination of field hospitals) - MDRAB (Genome contains alien DNA gained through horizontal gene transfer) - Treatment: imipenem, polymyxins

Answer 34

- GI tract inhabitants: some permanent, some transient, some only if diseased - Bacteriocins - Many have fimbriae; may cause UTI's - Most frequent cause of diarrheal illnesses - identification involves selective media to inhibit normal microbiota and encourage pathogens

Answer 35

- Escherichia coli - Shigella spp. - Salmonella - Klebsiella pneumoniae - Serratia marcensens - Proteus spp - Yersinia spp. (Y. pestis causes bubonic plague)

Answer 36

-nonenteric -Virulence factors: capsule protects against phagocytosis, endotoxin, coagulase -Bubonic plague or black death -Symptoms: Bubo (swollen lymph nodes); hemorrhaging under skin -Transmission: >Vector- rat flea Xenopsylla cheopsis = septicemic plague >Inhalation- pneumonic plague

Answer 37

- V. cholerae: "rice water stools" | - v. parahaemolyticus: halophile; 10 minute generation time

Answer 38

pathogen of domestic animals; also humans

Answer 39

- "blood lover". misnamed; HIB - causes respiratory infection, meningitis; ear aches - does not cause the flu

Answer 40

Gram Negative; flexible helical motile by axial filaments - Treponema pallidum - Borrelia burgdorferi - Leptospira spp

Answer 41

- Syphilis, Congenital Syphilis - Chancre (sore)--> Rash--> Latent--> Gummas (rubbery gummas; die of brain disease) - Penicillin G

Answer 42

- Borreliosis or Lyme Disease - cold (rash), neuro/cardio symptoms, arthritis - Treatment: tetracycline or derivatives - Transmitted by Vector: deer tick Ixodes

Answer 43

- Transmitted in dried urine of domestic pets (contact with mucus membranes or skin abrasions) - Principle targets: kidneys, liver, eyes, brain - Symptoms: sudden high fever, chills, headache, muscle aches, conjunctivitis, vomiting - Treatment: Penicillin or Tetracycline

Answer 44

gastrointestinal infections

Answer 45

causes stomach ulcers

Answer 46

human intestinal tract; peritonitis

Answer 47

- Gram (-) bacilli (rod-shaped) - Transmitted usually by arthropod vector - Grows intracellularly in host cell; responds to tetracycline - Rickettsia spp. (R. ricketsii, R. prowazeki, R. typhi) - Ehrlichia spp. - Bartonella henselae

Answer 48

Rocky Mountain spotted fever | -dermacentor variables (dog tick)

Answer 49

(Louse-borne Typhus aka epidemic typhus) | Pediculus humanus corporis

Answer 50

Endemic Murine typhus - host reservoir: rodents - Vector: Xenopsylla cheopsis (rat flea)

Answer 51

- Gram (-), rickettsia-like, obligate intracellular bacterium - Tickborne diseases with host reservoir being animals, especially deer - Two distinct forms: HGE, HME

Answer 52

- Aerobic, Gram (-) bacterium | - Transmitted by bite or scratch (cat to cat by flea)

Answer 53

-Gram (-) coccoid -Transmitted by air or direct contact (STD) -Grows intracellularly in a host cell -3 stages: reticulate bodies that reproduce in host; intermediate bodies; elementary bodies are infectious) -Two Genera: >Chlamydia >Chlamydophila

Answer 54

Chlamydia trachomatis

Answer 55

- Chlamydophila psittaci | - Chlamydophila pneumoniae

Answer 56

- Mycoplasma pneumoniae - no cell walls; pleomorphic; very small - Gram (-) type reaction - requires sterols in medium (does not produce its own sterols) - causes Primary Atypical Pneumonia aka Walking Pneumonia - Responds to tetracycline

Answer 57

- Francisella tularensis - Legionella pneumoniae - Acinetobacter baumannii - Brucella spp - Bordetella pertussis - Pseudomonas

Chapter 18-21 Flashcards

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