SM_240b: UTI

Question 1

Describe pathogenesis of UTIs

Answer 1

UTI pathogenesis

• Ascending: gut -> urethra -> bladder
• Adhesins: specific, phase vary

Question 2

E. coli adheres to epithelial cells through ___

Answer 2

E. coli adheres to epithelial cells through fimbriae (pili)

• Type 1 and P
• People infected with UTI have more bacteria adhering to epithelial cells

Question 3

Describe key early events in UTI pathogenesis

Answer 3

Key early events in UTI pathogenesis

1. Local IL-8 / IL-6 production
2. Neutrophil influx
3. Urothelial apoptosis
4. Bacterial invasion
5. Intracellular UPEC proliferation

Question 4

Describe host factors that promote colonization in UTI

Answer 4

Host factors that promote colonization in UTI

• Sexual activity: increase inoculation
• Spermicide: increase binding
• Estrogen depletion: increase binding
• Antimicrobials: decrease indigenous flora

Question 5

Describe host factors that facilitate ascent in UTI

Answer 5

Host factors that facilitate ascent in UTI

• Catheterization
• Urinary incontinence
• Fecal incontinence
• Residual urine with ischemia of bladder wall

Question 6

Describe host factors that reduce urine flow in UTI

Answer 6

Host factors that reduce urine flow in UTI

• Outflow obstruction, prostatic hyperplasia, prostatic carcinoma, urethral stricture, foregin body (calculus)
• Neurogenic bladder
• Inadequate fluid uptake (dehydration)

Question 7

___ is responsible for most UTIs

Answer 7

E. coli is responsible for most UTIs

• Staphylococcus saphrophyticus, Proteus, Klebsiella, Enterococci, Pseudomonas, Seratia, and Acinetobacter also

Question 8

Cystitis presents with ____, ____, and ____

Answer 8

Cystitis presents with dysuria, urgency, and frequency

Question 9

Pyelonephritis presents with ___, ___, ___, and ___

Answer 9

Pyelonephritis presents with cystitis, fever, chills, and flank pain

Question 10

Prostatitis presents with ___, ___, and ___

Answer 10

Prostatitis presents with cystitis, fever, and prostate tenderness

Question 11

Describe diagnosis of UTI

Answer 11

UTI diagnosis

• Collection -> void -> catheter -> SPA (increasing accuracy)
• Urinalysis (formed elements): WBC, RBC, bacteria
• Culture (type and number of bacteria)

Question 12

___ is one method to assess antimicrobial susceptibility

Answer 12

Disk diffusion is one method to assess antimicrobial susceptibility

Question 13

Describe different antimicrobials used for UTI

Answer 13

Antimicrobials used for UTI

Question 14

Collateral damage of antimicrobial therapy for UTI is ____, ____, and ____

Answer 14

Collateral damage of antimicrobial therapy for UTI is

• Associated with use of broad-spectrum cephalosporins and fluoroquinolones
• Selection of drug-resistant organisms
• Colonization or infection with multi-drug resistant organisms

Question 15

Describe UTI

Answer 15

UTI

• Symptoms: 100%
• Urinalysis w/ pyuria / bacteria; 50%
• Culture > 10² cfu/mL: 70%

Question 16

UPEC allows formation of ____ in UTI

Answer 16

UPEC allows formation of intracellular bacterial communities in UTI

Question 17

Describe uncomplicated UTIs

Answer 17

Uncomplicated UTIs

• Normal urinary tract (bladder or kidney): medical and imaging
• Poor response to therapy: imaging

Question 18

Describe complicated UTIs

Answer 18

Complicated UTIs

• Abnormal urinary tract (all men and children)
• Imaging and medical and/or surgery
• Remove or correct abnormality in urinary tract

Question 19

UTI can be ___, ___, or ___

Answer 19

UTI can be first / isolated, unresolved, or recurrent (reinfection or persistence)

Question 20

Describe uncomplicated cystitis

Answer 20

Uncomplicated cystitis

• Isolated / first: nitrofurantoin, TMP / SMX, or fosfomycin (could also use fluoroquinolone or B-lactam)
• Recent antibacterial therapy: fluoroquinolone
• Unresolved: fluoroquinolone if not used before but otherwise nitrofurantoin, TMP / SMX, or fosfomycin

Question 21

Describe recurrent uncomplicated cystitis

Answer 21

Recurrent uncomplicated cystitis

• Reinfection (different bacteria): long interval, medical therapy
• Persistence (same bacteria): short interval, surgery

Question 22

Describe management of uncomplicated recurrent cystitis due to reinfection

Answer 22

Uncomplicated recurrent cystitis due to reinfection

• Using spermicides, condoms, foam -> increases bacterial adherence: use alternative birth control
• Post-menopausal -> low estrogen increases bacterial adherence: vaginal estrogen creams
• Prophylaxis: nightly with TMP / SMX, nitrofurantoin, or cephalosporin
• Prophylaxis: peri-intercourse with fluoroquinolone
• Therapy: self-start with culture and fluoroquinolone

Question 23

Describe management of uncomplicated recurrent cystitis due to recurrence

Answer 23

Uncomplicated recurrent cystitis due to recurrence

• Image
• Localize
• Source of infection: correct, remove, or suppress
• If no source of infection identified, consider low dose prophylaxis for 6 months

Question 24

Describe asymptomatic bacteriuria

Answer 24

Asymptomatic bacteriuria

• Status: complicated (pregnancy), uncomplicated (elderly)
• Site: bladder
• Pattern: first / isolated reinfection

Question 25

Describe management of asymptomatic bacteriuria

Answer 25

Asymptomatic bacteriuria * Pregnancy: cephalexin, amoxicillin-clavulanate, TMP-SMX (not in 3rd trimester), or nitrofurantoin * Elderly: no antimicrobial

Question 26

Describe management of acute pyelonephritis

Answer 26

Acute pyelonephritis * Rule out obstruction * If not obstructed -\> uncomplicated * If obstructed -\> complicated -\> relieve with percutaneous nephrostomy and retrograde urethral catheter

Question 27

Important to differentiate acute pyelonephritis from \_\_\_

Answer 27

Important to differentiate acute pyelonephritis from perinephric abscess * Symptoms and fever last for ≥ 5 days in perinephric abscess * Manage renal abscess with IV antimicrobials, percutaneous or open drainage, observation

Question 28

Describe prostatitis

Answer 28

Prostatitis * Status: complicated (acute or chronic) * Site: prostate * Acute: first / isolated or recurrent via reinfection * Chronic: recurrence via persistence

Question 29

Describe management of acute prostatitis

Answer 29

Acute prostatitis * Sepsis: fluoroquinolone, do NOT massage prostate * Recurrent persistence: TMP / SMX, fluoroquinolone / chronic suppression / intermittent symptomatic therapy

Question 30

Next step should be \_\_\_

Answer 30

Next step should be urinalysis

Question 31

Classify her infection

Answer 31

Classifying her infection * Status: uncomplicated * Site: bladder * Pattern: first / isolated

Question 32

The best management approach for this patient is \_\_\_\_

Answer 32

The best management approach for this patient is TMP-SMX for 3 days