Urinary Tract

Symptoms:

- Noncatheterized patients will typically have specific or localizing symptoms to the urinary tract: dysuria, frequency, urgency.

- In elderly patients (non-catheterized or catheterized) in the absence of localizing symptoms, the following signs/symptoms do NOT warrant investigation or treatment for UTI:

• dizziness

• increased falls

• decreased appetite

• altered behavior

• confusion/disorientation.

- Before attributing delirium to UTI, always rule out/treat the following:

• dehydration

• new medication/drug interactions

• trauma

• hypoxia

• hypoglycemia

• infections other than UTI.

Investigations:

- A negative urinalysis/microscopy for pyuria excludes UTI in most cases.

- In symptomatic (dysuria, frequency, urgency) premenopausal women, urinalysis (dipstick or microscopy) for pyuria is highly sensitive and the preferred diagnostic technique.

- In elderly patients, catheterized patients, and patients with an abnormal urinary tract, a urinalysis showing bacteria or pyuria (WBC in urine) or a urine culture showing bacteria cannot differentiate between asymptomatic bacteriuria (bacterial colonization of the bladder) and UTI.

- Urine culture is NOT recommended for abnormal urinalysis in the elderly in the absence of UTI symptoms.

- Urine culture is also NOT recommended for:

• cloudy/foul-smelling urine in the absence of UTI symptoms

• blocked catheter

• replacement/insertion of catheter

• test of cure (unless patient not responding to therapy for a documented symptomatic UTI, or pregnant)

• routine screen/standing order.

- If urine cultures indicated, submit urinalysis and urine culture. Ensure proper urine collection:

• collect midstream urine (MSU) sample no sooner than 2 hours after last voiding

• cleanse prior to collection of MSU (essential).

- ≥10⁸ cfu/L - significant colony count indicative of urinary tract infection WITH signs & symptoms. NB: some laboratories only report a maximum colony count of ≥10⁷ cfu/L.

- ≥10⁶ cfu/L - may be significant in females with pyuria/dysuria syndrome; males, in/out catheter specimens, or suprapubic aspirate WITH signs and symptoms.

- ≥10⁵ cfu/L - significant colony count for suprapubic aspirate or cystoscopy specimens in patients with signs and symptoms.

- ≥3 mixed organisms - probable contamination. May be significant in adults with complicated UTI.

- Blood culture recommended if:

• febrile (>38°C)

• signs & symptoms of pyelonephritis (costovertebral angle tenderness, flank pain)

• immunocompromised.

Antimicrobial therapy:

- Spontaneous improvement/recovery occurs in up to 50% of women presenting with UTI symptoms. In hemodynamically stable, afebrile patients when the diagnosis of symptomatic UTI is in doubt or symptoms are mild, delaying antibiotic treatment while increasing fluid intake (oral, SC, IV), is a reasonable option, as long as patients are monitored.

- Amoxicillin is NOT recommended empirically due to unacceptably high E. coli resistance.

- Knowledge of local susceptibility patterns, ideally stratified by age, gender and setting (community, hospital, long term care), is essential for choosing empiric therapy. The threshold for the prevalence of resistance above which an antibiotic is not recommended for empiric treatment is:

• 20% for TMP/SMX in cystitis

• 10% for quinolones in pyelonephritis.

- Quinolones – do not use moxifloxacin as inadequate urinary concentrations.

- Nitrofurantoin and fosfomycin should NOT be used for pyelonephritis or urosepsis due to poor renal tissue and serum concentrations.

- Antifungal prophylaxis in women receiving antibiotic therapy for UTI is NOT routinely recommended.