[Role of direct radionuclide cystography and renal study by dimercaptosuccinic acid (DMSA) in the diagnosis and follow-up of vesicoureteral reflux].
AIM: To evaluate the role of isotopic studies in the diagnosis and follow-up of vesicoureteral reflux (VUR) and to present the results of our current protocol. MATERIAL AND METHODS: Forty three patients with VUR were retrospectively studied with a mean follow-up of 43 years (1-11 years). VUR was diagnosed by voiding cystourethrography and followed-up by direct radionuclide cystography. During the follow-up all patients were studied by means of renal DMSA scintigraphy (21 were also studied during the acute phase of febrile urinary tract infection). RESULTS: Eighty three renal units were examined. Voiding cystourethrography was positive for VUR in 49 renal units (59%; 8 grade I, 18 grade II, 15 grade III, and 8 grade IV). During the follow-up, direct radionuclide cystography showed decrease or disappearance of VUR in 29 renal units (35%; 4 grade I, 16 grade II, 7 grade III, and 2 grade IV). DMSA studies performed during the follow-up showed cortical lesions in 17 renal units (5 with VUR grade II, 7 with grade III, and 5 grade IV). Nine of 21 patients examined by DMSA during the acute phase of febrile urinary tract infection showed cortical damage (43%), and 6 of them (67%) progressed to cortical lesion in the follow-up DMSA. CONCLUSIONS: The present protocol allows for the correct diagnosis and control of VUR, the early detection of acute renal damage, and the control of its evolution.