ABSTRACT
BACKGROUND: Corynebacterium urealyticum may produce severe urinary tract infections (UTI) in patients with renal transplantation (RT). The aim of this study was to define the prevalence, clinical spectrum and risk factors for the development of symptomatic UTI in RT receptors with bacteriuria by C. urealyticum. METHODS: The clinical data of RT patients with bacteriuria by C. urealyticum diagnosed in the Hospital Doce de Octubre in Madrid from January 1990 to September 1993 were retrospectively reviewed. The patients corresponded to two clearly differentiated periods. In the first, the presence of C. urealyticum was not actively sought in the urine sample while in the second an intentional search was carried out in all the RT with a selective culture medium containing different antibiotics, Tween-80 and urea to facilitate C. urealyticum identification and growth. RESULTS: C. urealyticum was isolated in the urine of 46 patients (14% of the RT performed in the study period). In the first phase 16 cases were diagnosed with 30 being found in the second with the selective medium. Bacteriuria by C. urealyticum was symptomatic in 18 patients (39%): 12 acute cystitis, one encrusted cystitis (IC), and 5 encrusted pyelitis (IP). Of the symptomatic patients 39% had a history of prolonged vesical catheterization, 27% carried ureteral catheterization and 50% had undergone other urologic manipulations. The clinical consequences were important with development of obstructive uropathy and alteration in renal function (28%), need for surgery (33%) and graft loss (5.5%). All the C. urealyticum strains were sensitive to vancomycin and teicoplanin which were useful in the treatment although the most severe cases (IC, IP) required surgery. CONCLUSIONS: The prevalence of UTI by Corynebacterium urealyticum is high in RT patients. Occasionally, these infections may have severe consequences, particularly in patients with a history of urologic manipulation, if early diagnosis is not performed and adequate antibiotic treatment given. A selective culture medium should be used to isolate C. urealyticum in RT patients.
