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Flashcards in UTIs Deck (22)
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1
Q

UTI tests

A
Urine dipstick/UA
URI-cult CLED/EMB
Gram stain
Culture
Abx susceptibility
2
Q

CLED/EMB

A

QUANTITATIVE - CFU/mL

EMB - Selective for G-
CLED - Determines ability to ferment

3
Q

CFU/mL consistent with UTI

A

5x10^4

4
Q

Cells seen on HPF of UTI specimen

A

2-5 WBC OR

15 bacteria

5
Q

UTI pathogens

A
E. coli
Klebsiella spp
Proteus spp
Enterococcus spp
Staphylococcus saprophyticus
Streptococcus (Group B)
Pseudomonas aeruginosa
6
Q

Most common cause of UTI

A

Uropathogenic E. coli (UPEC)

7
Q

E. coli morphology

A

Gram negative
Flagellated
Encapsulated (K1) strains = meningitis

8
Q

UPEC transmission

A

Fecal contamination

9
Q

UPEC virulence factors

A

P fimbriae (pili)***
Dr adhesins
Alpha & beta hemolysins
K (capsular) antigen - typically seen in upper or chronic UTI

10
Q

Proteus morphology

A

Gram negative
Bacilli
Possess fimbriae

11
Q

Proteus species that cause UTI

A

P. vulgaris (immunocompromised)***

P. mirabilis (community acquired)

12
Q

P. vulgaris diagnosis

A
  • “Swarming” on culture agar (CLED prevents swarming)

- Produce UREASE (unique)

13
Q

Struvite stones

A

Magnesium ammonium phosphate

Unique to P. vulgaris (due to urease activity)

14
Q

S. saprophyticus morphology

A

Gram positive
Coagulase negative
Staphylococcus

15
Q

S. saprophyticus key notes

A
  • Normal flora of female genital tract
  • SECOND leading cause of UTI
  • Prominent in females ages 17-27 (sexually active)
16
Q

“Honeymoon cystitis”

A

S. saprophyticus

17
Q

S. saprophyticus virulence

A

Adhesins (lactosamine)

18
Q

S. saprophyticus diagnosis

A
  • Coagulase negative

- Differentiated from other coag neg due to NOVOBIOCIN resistance

19
Q

Group B strep (GBS)

A

S. agalactiae

20
Q

S. agalactiae morphology

A

Gram positive

Coccus

21
Q

S. agalactiae diagnosis

A
  • Gray-white colonies with a narrow zone of B-hemolysis
  • CAMP factor
  • AccuProbe
22
Q

S. agalactiae virulence

A

Capsular polysaccharide
Hyaluronidase
Collagenase
Hemolysin