Renal damage in vesico‐ureteric reflux

OBJECTIVE To detect the different extent of renal parenchymal involvement in primary vesico‐ureteric reflux (VUR), and to evaluate the relationship between VUR grade, patient age and different patterns of parenchymal damage. PATIENTS AND METHODS This blinded retrospective study included 197 consecutive children (mean age 4.26 years, range 1 month to 13 years) with primary VUR detected by voiding cysto‐urethrography (VCUG), 99mTc‐dimercaptosuccinic acid (DMSA; 120 MBq/1.73 m2) renal scintigraphy, with scanning for 3 h after intravenous injection. An abnormal DMSA scan was classified into three subtypes: cortical defects as a single scar (SS), multiple cortical scarring (MS) and diffuse reduced uptake with small renal size. Renal absolute uptake (AU), and split‐kidney relative uptake were evaluated in refluxing and nonrefluxing renal units, and correlated with parenchymal damage and patient age. Student's t‐test and the chi‐square test were used for the statistical analysis. RESULTS In all, 282 refluxing and 112 nonrefluxing units were assessed. Renal damage was detected in 188 of 282 units with VUR (67%) and in 18 of 112 (16%) contralateral nonrefluxing kidneys. The mean AU was 18.7% in kidneys with VUR and 29% in nonrefluxing units (P