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Flashcards in Microbiology Deck (59):
1

what is the most common immunologic method?

latex agglutination

2

what is a DNA probe?

identify the bug and the way to attack it

3

which antibodies form first?

IgM (7-14 days in)

4

why would you use a 2 titer approach?

are you in acute phase of disease or are you getting better?

5

streptococci

gram positive in chains

6

Group A beta hemolytic strep

S. pyogenes
DOC penicillin and amoxicillin
dx by culture and rapid ID test
serological dx by anti-treptolysin (ASO)

7

what dz are assoc with S. pyogenes?

glomerulonephritis (rare)
rheumatic fever (rare)
pharyngitis
scarlet fever
cellulitis
TSS
necrotizing fascitis

8

what happens if strep is untreated in some of the situations?

rheumatic fever and glomerulonephritis

9

Group B beta hemolytic strep

S. agalactiae
causes neonatal septicemia and meningitis
source in maternal genital tract
dx with maternal vaginal culture
intradelivery antibiotics for positive mothers

10

what is also assoc with group B strep?

post partum endometritis

11

Group C beta hemolytic strep

primarily animal pathogens but may be normal human flora

12

Group F beta hemolytic strep

dental abscesses, but infection uncommon

13

Group G beta hemolytic strep

animal pathogen, but can be normal human flora

14

S. viridans

alpha hemolytic strep
gram +
most common skin contaminant but normal in oral, throat, GI

15

what is S. viridans also assoc with?

opportunistic infections, wounds, bacteremia

16

what is the most common cause of bacterial endocarditis?

S. viridans

17

S. pneumoniae

alpha hemolytic gram +
community acquired pneumonia
and pneumococcal bacteremia if left untreated
most strains sensitive to penicillin

18

what is assoc with S. pneumoniae?

otitis media, meningitis, in children and older adults

19

what do you do with S. pneumoniae infection?

C&S and latex agglutination of CSF

20

Group D non hemolytic strep

S. bovis (affects animal handlers)

21

Enterococcus

E. faecalis and E. faecium
causes 20% of bacterial endocarditis and 10% of UTI
also causes nosocomial infections producing vancomycin-resistant strains (VRE)

22

staphylococci

gram positive in clusters

23

Staph aureus

assoc with purulent inflammation and causes abscesses
*most common cause of bacterial endocarditis in drug users
causes endotoxin with causes TSS

24

what is MRSA?

methicillin resistant staph aureus
-cause of nosocomial infections

25

staph epidermidis

normal flora on skin
mostly assoc with indwelling devices (catheters, vascular grafts, joint prosthetics)
skin contaminant and eye surgery infection

26

staph saprophyticus

common cause of bacterial UTI
often antibiotic resistant

27

what color is gram positive?

blue

28

what color is gram negative?

red

29

neisseria gonorrhoeae

gram negative diplococci
causes gonorrhea
typically asx in females, but not in males
strains are becoming resistant
causes PID or salpingitis

30

neisseria meningitidis

most common type of meningitis in adults
dx by C&S and agglutination of CSF

31

moraxella catarrhalis

gram negative diplococci found in URI
most common with ear and sinus infection

32

E. coli

most common cause of UTI
most common cause of neonatal meningitis

33

E. coli O157:H7

hemorrhagic colitis

34

Klebsiella pneumoniae

a/w pneumonia in alcoholics and older adults
aspirated vomit

35

proteus

cause of UTI in pts in hospital
P. mirabilis and P. vulgaris
normal flora of GI

36

pseudomonas aeruginosa

nosocomial with UTI and septicemia
a/w severe burns, otitis externa and cystic fibrosis infections
known for high resistance and mortality

37

gardnerella vaginalis

causes bacterial vaginosis
dx by clue cells in wet mount of discharge

38

haemophilus

gram negative coccobacilli

39

H. influenzae

most important species of croup
a/w otitis media (children), sinusitis, meningitis, bacteremia and pneumonia

40

H. aegyptius

purulent conjunctivitis

41

H. ducreyi

causes venereal chancroid

42

pasteurella multocidas

dogs and cat bites
cellulitis occurs if left untreated

43

H. pylori

mucus covering gastric mucosa
dx with gastric biopsy culture, urea breath test
acute and chronic gastricits, duodenal ulcer and gastric CA

44

corynebacteria

gram positive bacilli

45

C. diphtheriae

most important corynebacteria

46

lactobacillus

normal genital tract flora

47

listeria monocytogenes

causes infection from contaminated food (cheese, salads)
dx by culture
most common presents with meningitis and bacteremia

48

clostridium perfringens

most common cause of gas gangrene
deep tissue wounds are more susceptible

49

clostridium tenani

causes tetanus (produces spores)
puncture wounds are at higher risk

50

clostridium botulinum

produces botulism
produces an endotoxin (spores germinate in anaerobic conditions)

51

clostridium difficile

pseudomembraneous colitis
a/w antibiotic use
major nosocomial infection

52

chlamydia

coccobacillary organism
can only be grown in living cells

53

chlamydia psittaci

associated with birds

54

chlamydia pneumoniae

causes about 10% of pneumonia

55

chlamydia trachomatis

causes lymphogranuloma venereum STD
huge lymph nodes in their groin
serology test
can cause urethritis and endocervicitis

56

mycoplasma pneumoniae

atypical pneumonia
chest x-ray is LL mottled infiltrates
most common in college freshman and military recruits

57

mycobacterium TB

acid fast bacillus

58

what is the dx value of bacteria in UTI?

>100,000 cfu/mL

59

why is sputum culture difficult?

can be contaminated with oropharyngeal bacteria

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