UTI

Question 1

What are common causative organisms of UTIs?

Answer 1

E. coli – most common
Staph. saprophyticus

**95% from GI tract

Question 2

In infants, (M, F) more commonly have UTI’s.

In 3-50 y/o, (M, F) more commonly have UTI’s.

Answer 2

M

F

Question 3

What age group has the highest rate of bacteriuria?

Answer 3

> 65

Question 4

What are contributing factors that increase # UTI’s in younger ages?

Answer 4

sex

pregnancy

Question 5

What contraceptives have increased incidence of UTI?

Answer 5

diaphragm/spermicide > spermicidal foam/condoms > oral contraceptives

Question 6

What is the most common route of infection?

Answer 6

95%: Ascending route (Urethral trauma, Intercourse, Instrumentation, Diaphragm use)

<5%: Hematogenous route

Question 7

Mechanisms for pathogenesis of UTIs?

Answer 7

Adhesion
Colonization
Invasion
Phase variation

Question 8

What bacterial factors contribute to UTI’s?

Answer 8

1. Uropathogenic E. coli = Virulence factors

2. Structural = adhesions on fimbriae (type 1 and p-)

Question 9

**ADD INFO ON PATHOGEN!

Answer 9

**

Question 10

Host Defense Mechanisms?

Answer 10

Bacterial growth inhibition
Urine flow
Epithelial cell turnover
Antibodies

Question 11

Predisposing host factors?

Answer 11

Urine flow obstruction
Female factors
Abnormal urine flow
Urethral trauma
Vesiculo-ureteral reflux
Instrumentation

Question 12

Clinical Manifestations of UTI of lower tract?

Answer 12

Frequency of urination
Dysuria  - painful urination
Turbid urine
Suprapubic discomfort
Hematuria
Asymptomatic cystitis

Question 13

Clinical Manifestations of UTI of upper tract?

Answer 13

Fever
Chills
Flank pain and “CVAT”
Asymptomatic pyelonephritis

Question 14

Dx of UTI?

Answer 14

Microscopic urinalysis
Gram stain of urine
Urine culture
Blood cultures (PRN)
Screening tests

Question 15

Complications of UTI:

Answer 15

Gram negative sepsis
Intrarenal or extrarenal abscess
Chronic renal insufficiency
Struvite renal calculi
Recurrent infection

Question 16

Prevention of UTI:

Answer 16

Proper use of urinary catheterization

Correction of anatomic abnormalities

Prophylactic antibiotics - RARELY

Question 17

Abx treatment for asymptomatic bacteriuria in elderly?

Answer 17

none!

Question 18

Abx treatment of upper tract UTI?

Answer 18

1-6 weeks (IV vs oral therapy)

Question 19

Abx treatment of upper tract UTIs for M vs F?

Answer 19

Males: 1 week

Females: 1-3 days (but longer if complicated UTI)

Question 20

pus in urine (inflammation or infxn)

Answer 20

Pyuria

Question 21

inflamm. of renal pelvis (upper UTI)

Answer 21

Pyelonephritis

Question 22

symptoms of UTI (frequency, urgency, dysuria), but no apparent source of infxn


Answer 22

Acute urethral syndrome

Question 23

How do birth control methods increase UTI risk?

Answer 23

spermicide changes flora of vagina

diaphragm changes angle of urethra, may ↑ reflux

Question 24

Abx which are best at concentrating more in inflamed kidney than uninflamed

Answer 24

Aminoglycosides (tobramycin, gentamicin)

Question 25

Abx which concentrate about the same in inflamed vs uninflamed

Answer 25

Sulfonamides and trimethoprim

Question 26

Abx which concentrate LESS in inflamed kidney than uninflamed

Answer 26

Ampicillin/cephalothin

Question 27

Abx which can treat prostatitis

Answer 27

Cipro

Question 28

impairs phagocytosis

Answer 28

Capsular polysaccharide [K antigen]

Question 29

Proteins at the end of type 1 fimbrae can bind:

Why is this important?

Answer 29

mannose in host tissues (=attachment)

Mannose present in lower UT → lower UTI

Question 30

P antigen present in:

Why is this important?

Answer 30

in renal pelvis

expression of P-fimbriae → pyelonephritis