[Evaluation of renal lesions using 99mTc-DMSA in children with urinary tract infection and the relation with vesicoureteral reflux]

Abstract

Objective. Paediatric patients with urinary tract infection (UTI) have risk of developing renal scarrings. Although it is known that vesicoureteral reflux (VUR) predisposes to UTIs and it seems to have an important role in the development of renal lesions, some recent published studies question that relation. The aim of the study was to evaluate renal scarring by using renal scintigraphy 99mTc-DMSA and see the relation with or without the presence of VUR. Material and methods. We evaluated retrospectively a total of 230 patients (460 renal units), mean age: 11 months (range: 12d-5y), with UTI probed by urinoculture. All were studied with voiding cistourethrography (MCU) to evaluate the presence or absence of VUR. Patients were evaluated with 99mTc-DMSA scan 6 months after UTI to determine if UTI caused renal scarring. Results. Renal scans with 99mTc-DMSA 6 months post-infection were abnormal in 62 renal units, affecting 54 patients (23%). From all patients studied, 110 were diagnosis of VUR being affected 161 renal units, 43 of them (27%) presented renal scarrings. From the remaining 120 patients without VUR that is 240 renal units, 19 of them (8%) presented parenchymatous damage. Conclusion. Renal scarring resulting from UTI are in some cases related to VUR, but sometimes are caused by the infection itself. Not all patients with VUR develop renal lesions, and neither the presence of VUR always predispose children to renal lesions. MCU and direct isotopic cystography are useful for diagnosis of VUR but we shouldn't avoid 99mTc-DMSA scan in the management of children with UTI.