SM_240b: UTI Flashcards
Describe pathogenesis of UTIs
UTI pathogenesis
- Ascending: gut -> urethra -> bladder
- Adhesins: specific, phase vary
E. coli adheres to epithelial cells through ___
E. coli adheres to epithelial cells through fimbriae (pili)
- Type 1 and P
- People infected with UTI have more bacteria adhering to epithelial cells
Describe key early events in UTI pathogenesis
Key early events in UTI pathogenesis
- Local IL-8 / IL-6 production
- Neutrophil influx
- Urothelial apoptosis
- Bacterial invasion
- Intracellular UPEC proliferation
Describe host factors that promote colonization in UTI
Host factors that promote colonization in UTI
- Sexual activity: increase inoculation
- Spermicide: increase binding
- Estrogen depletion: increase binding
- Antimicrobials: decrease indigenous flora
Describe host factors that facilitate ascent in UTI
Host factors that facilitate ascent in UTI
- Catheterization
- Urinary incontinence
- Fecal incontinence
- Residual urine with ischemia of bladder wall
Describe host factors that reduce urine flow in UTI
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)
___ is responsible for most UTIs
E. coli is responsible for most UTIs
- Staphylococcus saphrophyticus, Proteus, Klebsiella, Enterococci, Pseudomonas, Seratia, and Acinetobacter also
Cystitis presents with ____, ____, and ____
Cystitis presents with dysuria, urgency, and frequency
Pyelonephritis presents with ___, ___, ___, and ___
Pyelonephritis presents with cystitis, fever, chills, and flank pain
Prostatitis presents with ___, ___, and ___
Prostatitis presents with cystitis, fever, and prostate tenderness
Describe diagnosis of UTI
UTI diagnosis
- Collection -> void -> catheter -> SPA (increasing accuracy)
- Urinalysis (formed elements): WBC, RBC, bacteria
- Culture (type and number of bacteria)
___ is one method to assess antimicrobial susceptibility
Disk diffusion is one method to assess antimicrobial susceptibility
Describe different antimicrobials used for UTI
Antimicrobials used for UTI
Collateral damage of antimicrobial therapy for UTI is ____, ____, and ____
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
Describe UTI
UTI
- Symptoms: 100%
- Urinalysis w/ pyuria / bacteria; 50%
- Culture > 102 cfu/mL: 70%
UPEC allows formation of ____ in UTI
UPEC allows formation of intracellular bacterial communities in UTI
Describe uncomplicated UTIs
Uncomplicated UTIs
- Normal urinary tract (bladder or kidney): medical and imaging
- Poor response to therapy: imaging
Describe complicated UTIs
Complicated UTIs
- Abnormal urinary tract (all men and children)
- Imaging and medical and/or surgery
- Remove or correct abnormality in urinary tract
Describe uncomplicated cystitis
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
Describe recurrent uncomplicated cystitis
Recurrent uncomplicated cystitis
- Reinfection (different bacteria): long interval, medical therapy
- Persistence (same bacteria): short interval, surgery
Describe management of uncomplicated recurrent cystitis due to reinfection
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
Describe management of uncomplicated recurrent cystitis due to recurrence
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
Describe management of asymptomatic bacteriuria
Asymptomatic bacteriuria
- Pregnancy: cephalexin, amoxicillin-clavulanate, TMP-SMX (not in 3rd trimester), or nitrofurantoin
- Elderly: no antimicrobial
Describe management of acute pyelonephritis
Acute pyelonephritis
- Rule out obstruction
- If not obstructed -> uncomplicated
- If obstructed -> complicated -> relieve with percutaneous nephrostomy and retrograde urethral catheter
Important to differentiate acute pyelonephritis from ___
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
Describe management of acute prostatitis
Acute prostatitis
- Sepsis: fluoroquinolone, do NOT massage prostate
- Recurrent persistence: TMP / SMX, fluoroquinolone / chronic suppression / intermittent symptomatic therapy
Next step should be ___
Next step should be urinalysis
Classify her infection
Classifying her infection
- Status: uncomplicated
- Site: bladder
- Pattern: first / isolated
The best management approach for this patient is ____
The best management approach for this patient is TMP-SMX for 3 days
