Urinary Tract Infections (UTIs) Management

Specimen Transport

• Specimens must be sent to the lab and processed as quickly as possible
• Required information: method of collection, time and date of collection
• Specimens not received by the lab within 1-2 hours must be refrigerated
• Urine specimens not received within 24 hours or not refrigerated will be rejected by the laboratory, unless transported in a Boric acid tube

Urinary Tract Infections (UTIs)

• Not all patients with suspected UTI need to be cultured
• Empiric therapy is based on the most probable pathogens, type of infection (lower or upper tract), local rates of resistance, and whether it's an acute or recurrent infection

Typical Treatment Regimens

• Uncomplicated cystitis: Nitrofurantoin, Fosfomycin, TMP/SMX (if resistance < 25%), Doxycycline (2nd line), Ciprofloxacin / norfloxacin (2nd line)
• Pyelonephritis: β-lactam + aminoglycoside or Ciprofloxacin / levofloxacin

UTI Definitions

• Prostatitis: inflammation/infection of the prostate gland, may present as acute or chronic
• Intrarenal abscess/perinephric abscess: collection of pus in the kidney or surrounding soft tissue

Uncomplicated vs. Complicated UTIs

• Uncomplicated UTIs: occur in patients with normal genitourinary tracts, typically in non-pregnant premenopausal women
• Complicated UTIs: involve structural or functional abnormality of the genitourinary tract, pregnant women, elderly, men, children, chronic symptoms, comorbid illness, or immunocompromised patients

Complicated Infections

• Underlying abnormality that predisposes patients to UTI or makes treatment more difficult

Recurrent Infections

• Relapse: recurrence of infection by the same organism after discontinuation of treatment (possibly due to resistance)
• Re-infection: recurrence of infection by a different organism after discontinuation of treatment

Diagnosis: Rapid In-office Lab Testing

• Urinalysis by dipstick testing: detects nitrites and leukocytes, which are markers of infection
• Nitrite detection is reasonably sensitive for gram-negative bacteria, but highly specific
• Leukocyte detection is sensitive but not specific
• Combined detection of nitrites and leukocytes is highly sensitive and specific when combined with clinical findings
• Red blood cell detection is not sensitive or specific

Quantitative Culture

• Urine culture: significant bacteriuria is defined as > 105 bacteria / ml (or 10^8 / litre)
• Lower numbers may be significant in children and in catheter-collected specimens

Specimen Collection

• Clean catch mid-stream specimens: most frequently used method, urethra is cleaned prior to collection, first void urine is allowed to pass to clear the urethra
• Collection bags (children): used in young children lacking bladder control, often contaminated, and most meaningful result is a negative culture
• Indwelling catheters: urine obtained by inserting a needle into the catheter or through the diaphragm, preferably obtained from a new catheter rather than an old one
• Suprapubic aspiration / straight catheters: invasive, specimen obtained directly from the bladder

Assess your knowledge of UTIs, from empiric therapy to transportation of urine specimens, and patient management considerations. Test your understanding of treatment options and lab procedures.