Color and power Doppler sonography versus DMSA scintigraphy in acute pyelonephritis and in prediction of renal scarring

Abstract

Capabilities of color and power Doppler sonography (DS) were prospectively evaluated for diagnosis of acute pyelonephritis and for prediction of scarring by comparison with 99mTc-dimercaptosuccinic acid scintigraphy (DMSA).

Methods: Fifty-seven children (mean age, 5 +/- 3 y) with acute pyelonephritis were investigated by biologic testing, DS (DS 1), and DMSA (DMSA 1). Patients who were <6 mo old or had high-grade reflux or obstruction were excluded. Forty-five children had a clinical follow-up examination, biologic testing, DS (DS 2), and DMSA (DMSA 2) at a mean of 7 +/- 2 mo after acute infection. Sonography (gray-scale and DS) was performed by 1 experienced radiologist who was unaware of patient data. DMSA studies were interpreted by 2 physicians who were unaware of patient data.

Results: Temperature, neutrophil count, and C-reactive protein value were significantly higher in patients with abnormal DMSA 1 findings than in those with abnormal DS 1 findings (P < 0.05). When compared with DMSA 1, DS 1 had a sensitivity and specificity of 80% and 81%, respectively. At follow-up, all clinical and biologic data had normalized. Scarring after infection occurred in 51% of children. When compared with DMSA 2, DS 1 had positive and negative predictive values of 57% and 75%, respectively, and DMSA 1 had respective values of 62% and 100%. Reflux was not considered a good predictor of scarring.

Conclusion: DS and DMSA results were concordant in 81% of kidneys with acute pyelonephritis. The predictive value of DS for renal scarring was not considered sufficiently high for DS to be used in routine practice.