Prevalence of urinary tract infection and renal scars in patients with diabetes mellitus

In a case control study, we assessed the prevalence of bacterial urinary tr act infections (UTI) and renal scarring in 155 consecutive type I (n=102) a nd type 2 (n=53) diabetic individuals and 128 healthy controls. Subjects wh o received antibiotics during the past 6 months, pregnant women and those w ith overt renal failure were excluded. In all subjects, urine culture and 9 9m Technetium (Tc) dimercapto-succinic acid renal scan was performed. UTI w as diagnosed if two consecutive urine cultures grew the same organism with at least 10(5) colony forming unit (cfu)/ml in asymptomatic and at least 10 (4) cfu/ml in symptomatic subjects, respectively. Renal scan was considered abnormal if focal or multiple tracer uptake defects and/or break in cortic al outline were observed. The prevalence of UTI in diabetes mellitus was hi gher, when compared to that in controls (9% vs. 0.78%, P=0.005). Escherichi a coli was the most commonly grown organism (64.3%), followed by Staphylocc ocus aureus (21.4%) and Klebsiella pneumoniae (14.3%). Prevalence of renal scarring was higher in patients with diabetes (28/155, 18.0%), when compare d to that of controls (7/128, 5.4%, P=0.002). Fifty percent of patients wit h diabetes and UTI had renal scarring. The prevalence in diabetics with no UTI was also higher, when compared to controls (14.8 vs. 5.5%, P<0.01). The prevalence of UTI as well as renal scarring was significantly higher in fe males, when compared to male diabetics. No significant difference in vascul ar events, hypertension, proteinuria, renal function tests and HbAl was obs erved in patients with and without renal scar. Thus, patients with diabetes mellitus have 10- and 3-folds increased risk of UTI and renal scarring, re spectively. The results could help prioritize protocols for management of U TI among patients with diabetes mellitus. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.