Chemoprophylaxis and suppressive therapy in the management of urinary tract infections.

Urinary tract infections are among the most common infectious diseases encountered in domiciliary and hospital practice. The ease of treatment and prophylaxis depends on host factors and the nature of invading microbe. Prophylaxis is often effective in preventing infection from exogenous or endogenous sources. It is useful in females with frequent, recurrent infections, in males with a persistent prostatic focus, in renal transplant recipients, and following instrumentation of the urinary tract. It is often useful in children with vesico-ureteral reflux and in patients undergoing urological operations. It is ineffective in patients with long-term indwelling catheters. A wide variety of prophylactic tactics is available. These are designed to meet the special needs of individual patients. Patient counselling is a key feature of a good prophylactic regimen. Desirable features of antimicrobial drugs used for prophylaxis include good oral absorption, minimum toxicity, high concentrations in the urine, minimum potential for development of resistance and low cost. Suppressive therapy is often ineffective and cannot substitute for corrective surgical procedures. It is important to recognize microbial failure and to avoid unnecessary therapy.