Diagnosis and therapy for urinary tract infections

Abstract

The onset of urinary tract infections requires careful collection of a urine specimen and use of selective screening and culture techniques. Account must be taken of the patient's status and history. Enterobacteriaceae and gram-positive cocci remain the most commonly isolated uropathogens. The knowledge that bacteria adhere to the uroepithelium has improved our understanding of the pathogenesis but has done little to alter diagnosis and therapy. An examination of host cell responses (leukocyturia, hematuria) and bacteria attached to bladder cells should assist the physician with diagnosis. Treatment of urinary tract infections should depend on culture sensitivity results for the uropathogens. Most urinary tract infections can be treated effectively with antimicrobial agents, and the introduction of broad-spectrum fluoroquinolones has proved useful in eradicating organisms from the urinary tract and prostate. The management of recurrent urinary tract infections involves active eradication of organisms with antibiotics, often given prophylactically. The use of lactobacilli therapy to prevent infection appears to have potential, based on preliminary in vivo results, but further studies are required. For catheter-related infections, antimicrobial penetration of bacterial biofilms remains a major problem, as does provision by the laboratory of accurate minimum inhibitory concentrations of antimicrobials required to penetrate the biofilms.