The Risk Factors of Renal Scar in Childhood Acute Pyelonephritis

ABSTRACT

PURPOSE: To observe the risk factors of renal scar in children with first acute pyelonephritis (APN) who had photopenic defects on initial 99mTc-DMSA spect renal scan. METHODS: Forty-seven children with first APN(M F=33 14) who were admitted to Ewha Womans University Hospital from September, 1993 to Febrary, 1998, were divided into renal scar group(N=17, Kidney unit(KU)=18) and non-scar group(N=30, KU=39) according to follow-up 99mTc-DMSA spect renal scan. The risk factors were compared between the two groups. RESULTS: There was no significant difference in age, gender, laboratory parameters, causative organism, a pattern of defect on initial 99mTc-DMSA spect renal scan, the presence of vesicoureteral reflux(VUR) and rate of febrile break-through infection between renal scar and non-scar group(P>0.05). The duration of fever before the treatement(3.4+/-2.94 vs. 2.1+/-2.29) and the rate of prolonged fever over 5 days[47.1%(8/17) vs 10.0%(3/30)] were significantly different between the two groups(P<0.05). The severity of VUR was also significantly higher in renal scar group than non-renal scar group(P<0.05, r=0.64). CONCLUSION: Duration of fever before the treatment, prolonged fever and high-grade VUR were risk factors of renal scar in childhood APN. Prompt treatment, especially in children with severe VUR, is important to prevent renal scars.