Prognostic Factors of Renal Defects on the Initial DMSA Scan in Children with Acute Pyelonephritis

Seon, Yeong Seon; Kwon, Duck Geun; Shin, Yun Hyea; Pai, Ki Soo

Abstract

PURPOSE
The purpose of this study is to determine if there are prognostic factors leading to permanent parenchymal damages to kidney in children after acute pyelonephritis.
METHODS
This study was conducted in 160 pediatric patients with acute pyelonephritis admitted to Ajou University Hospital from 2000 to 2005, whose renal cortical defects were confirmed by 99mTc-dimercaptosuccinic acid scintigraphy (DMSA scan). Along with the follow-up DMSA scan after 6 months, they were classified into two groups; recovered group (106) and scarred group (54). The clinical characteristics of each group were compared.
RESULTS
Among the total of 160 patients, 106 (66.3%) showed recovery of the initial defect (the recovered group), while 54 (33.8%) showed permanent defects on the follow-up DMSA scan (scarred group). Recovery rate was poor for patients of 1 year and older, or patients with the duration of fever and pyuria longer than 7 days. The recovery rate was poor in the patients with history of frequent febrile episodes and abnormal results of imaging studies, such as voiding cystourethrography (VCUG), ultrasonography.
CONCLUSION
The recovery rate of children with renal defects on DMSA scan with acute pyelonephritis was lower when the patient is older than 1 year, when the duration of fever and pyuria exceeded 7 days, and when the patients had the histories of frequent febrile episodes and had urinary tract abnormalities on imaging studies. These findings suggest that there may be under- or mis-diagnosis of acute pyelonephritis by pediatrician.