Complicated urinary tract infections in patients with voiding dysfunction

Complicated urinary tract infections (UTIs) occur in patients who have structurally or functionally abnormal urinary tracts -- in contrast to simple cystitis, which usually occurs in young, healthy females who have normal anatomy. Because of their abnormal anatomy, patients with complicated UTIs can be exceedingly difficult to treat. Successful treatment usually requires correction of the underlying anatomical problem, but this may not possible, so relapse of the infection is the general rule. Although most infections are still caused by Escherichia coli, many are caused by more exotic and highly resistant coliforms, such as citrobacter and pseudomonas. As well, gram-positive bacteria such as staphylococcus and enterococcus can be found. In patients with spinal cord injuries, high bladder pressure due to obstruction at the sphincter level can cause obstruction and/or reflux. In these patients, as well as in patients with benign prostatic hypertrophy, and in geriatric women, high residual bacteria levels prevent washout of bacteria. Other possibly significant risk factors include poor fluid intake, poor hygiene, and poor nutrition that results in decreased immunity. Finally, the unavoidable use of catheters actively introduces bacteria into the urinary tracts of these patients. Prevention by modifying as many of these risk factors as possible is essential to reduce attack rates of UTIs. Treatment must be guided by the results of urine cultures. Broad-spectrum coverage including anti-pseudomonal activity is preferable, and the fluoroquinolones, eg. ciprofloxacin or levofloxacin, seem to fit this bill perfectly. If possible, physicians should start by prescribing oral antibiotics for a minimum of 10 days and maybe for a lot longer, as indicated. There is no role for short-course therapy. Other options include oral, second-generation cephalosporins, or intravenous therapy with aminoglycosides and piperacillin. Physicians must be prepared to treat aggressively for prolonged periods. Unfortunately, reinvestigation, reculturing, and retreatment are usually required.