Risk Factors of Renal Scar After Acute Pyelonephritis in Children

ABSTRACT

PURPOSE: In this study we re-evaluated the known risk factors of pyelonephritic scarring in children. METHODS: A prospective study was performed on 36 acute pyelonephritis(APN) patients who were diagnosed as first acute pyelonephritis on 99mTc-DMSA scan between September 1998 and March 2000 in Masan Samsung Hospital. According to the prescence of remnant lesions on the 99mTc-DMSA scan performed 6 months after the first 99mTc-DMSA scan, the patients were divided into scar(Group A, N=15) and non-scar groups(Group B, N=21). We compared known risk factors of renal scarring between the two groups. RESULTS: There were no differences in age, sex, cultured organisms and CRP level between the two groups. Most of the initial 99mTc-DMSA scan results were not different but bilateral multiple lesions were much more common in group A(40.0% of Group A patients) compared with group B (9.5% of Group B patients). Moderate to high grade vesicoureteral reflux was also much more commonly observed in group A(46.6% of Group A patients) compared with group B(4.8% of Group B patients). CONCLUSION: Bilateral multiple lesion on initial 99mTc-DMSA scan and moderate to high grade vesicoureteral reflux at diagnosis of acute pyelonephritis may be risk factors associated with renal scarring after acute pyelonephritis in children.