Acute childhood pyelonephritis: predictive value of positive sonographic findings in regard to later parenchymal scarring.
OBJECTIVE
The authors evaluated the importance of positive sonographic findings in acute childhood pyelonephritis.


METHODS
A total of 290 children (91 boys, 199 girls, aged 4 days to 15 years [median, 394 days]) with clinically suspected acute pyelonephritis underwent initial renal gray-scale ultrasound (US) and dimercaptosuccinate scintigraphic examination within 3 days of onset. A total of 173 patients underwent color or energy US examination. One hundred fifteen children with normal scintigraphic or pathologic findings (other than acute pyelonephritis) were excluded from further study; 170 patients with abnormal scintigraphic findings underwent follow-up scintigraphic scanning 60-90 days later.


RESULTS
When pathologic structures other than acute pyelonephritis were not considered, the diagnostic value of gray-scale US was poor, with a sensitivity of 45.5%, a specificity of 86.6%, a positive predictive value of 88.8%, and a negative predictive value of only 40.6%. In regard to future renal scarring, gray-scale US had a positive predictive value of 67.7%, a negative predictive value of 40%, and a likelihood ratio of 1.16. Abnormal Doppler findings helped predict future scarring with a positive predictive value of 85.7%, a negative predictive value of 37.2%, a very low sensitivity of 26.9%, a high specificity of 90.6%, and a likelihood ratio of 2.87.


CONCLUSIONS
Positive US Doppler findings in children with clinically suspected acute pyelonephritis indicate the need for immediate treatment. A positive initial gray-scale US examination does not predict future renal scarring, but a positive Doppler examination indicates a high probability of scarring. Negative gray-scale or Doppler US does not exclude a diagnosis of acute pyelonephritis and it cannot predict an absence of future scarring.
Jéquier
S
S
Department of Radiology, University Hospital of Geneva, Children's Hospital, Switzerland.
Jéquier
J C
JC
Hanquinet
S
S
D000208:Acute Disease; D000293:Adolescent; D002614:Chelating Agents; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D002921:Cicatrix / Q000209:etiology*; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007674:Kidney Diseases / Q000209:etiology*; D016013:Likelihood Functions; D008297:Male; D011237:Predictive Value of Tests; D011704:Pyelonephritis / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D004113:Succimer; D018608:Ultrasonography, Doppler; D018615:Ultrasonography, Doppler, Color
D002614:Chelating Agents; D004113:Succimer