STENOTROPHOMONAS (XANTHOMONAS) MALTOPHILIA URINARY-TRACT INFECTION - A DISEASE THAT IS USUALLY SEVERE AND COMPLICATED

Background: Stenotrophomonas (Xanthomonas) maltophilia has emerged as a causative agent of serious nosocomial infections. However, well-docu mented cases of urinary tract infection with this organism have rarely been reported. Methods: Review of the medical records of patients adm itted to a large cancer center with cultures yielding S maltophilia fr om urinary sources during a 15-month period. Results: All urinary trac t infections were serious: 13 were complicated and two were acute unco mplicated pyelonephritis. The urinary tracts of 13 other patients were colonized with S maltophilia. Most of the colonized and infected pati ents were hospitalized with genitourinary malignancy, underwent urinar y catheterization, and were receiving antibiotics inactive against S m altophilia. Neutropenia and urinary structural abnormalities were sign ificantly associated with infection. The clinical course of infection was usually severe: fever (100%), sepsis disorder (47%), neutrophilia (70% of patients without neutropenia), bacteremia (13%), and death (7% ). Still, response to treatment was prompt. Conclusions: Stenotrophomo nas maltophilia urinary tract infection is usually associated with a s evere clinical course. Risk factors for urinary colonization by this o rganism include hospitalization, urinary catheterization, and administ ration of inactive antibiotics. Risk factors for urinary tract infecti on include neutropenia and urinary structural abnormalities. In the pr esence of these risk factors, treatment for S maltophilia should be co nsidered in patients with urinary colonization by the organism or in t hose with nosocomial urinary tract infection caused by an unknown path ogen and that is unresponsive to therapy with the antibiotics that are used to treat the common uropathogens.