Acute 99mTc DMSA scan predicts dilating vesicoureteral reflux in young children with a first febrile urinary tract infection

OBJECTIVE: This study aimed to examine the ability of acute 99mTc DMSA scan for predicting dilating (grades III-V) vesicoureteral reflux (VUR) after a first febrile urinary tract infection in children aged 2 years or younger. PATIENTS AND METHODS: All children underwent ultrasonography (US), 99mTc DMSA scan, and voiding cystourethrography. Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and receiver operating characteristic curves were performed to assess the diagnostic accuracy for predicting dilating VUR. Follow-up scan was performed at least 6 months after the acute infection to evaluate the presence of renal scarring (RS) or new scars. RESULTS: Of the 473 children analyzed (289 boys and 184 girls; median age, 5 months), 282 (59.6%) had abnormal acute 99mTc DMSA scan findings. There was VUR in 153 children (32.3%), whereas 95 (20.1%) had dilating VUR. The sensitivity and negative predictive value in predicting dilating VUR were 95.8% and 97.9%, respectively, for 99mTc DMSA and 97.9% and 98.6%, respectively, for combined US and 99mTc DMSA, whereas the positive and negative likelihood ratios were 1.90 and 0.08, respectively, for 99mTc DMSA and 1.57 and 0.06, respectively, for combined studies. On multivariate analysis, dilating VUR was a predictor for developing RS and new scars. CONCLUSIONS: Our results reveal the usefulness of acute 99mTc DMSA scan for predicting dilating VUR in children with a first febrile urinary tract infection. A voiding cystourethrography is indicated in only children with abnormalities found on a 99mTc DMSA and/or a US. The presence of dilating VUR predisposes to developing RS and new scars.