Is Nutcracker Syndrome Innocent?

Abstract

Objective: Nutcracker syndrome (NS) is defined by the compression of the left renal vein by the superior mesenteric artery. The incidence of NS and the exact treatment protocols are not well known. The objective of this study is to analyze children with NS and evaluate the prognosis in follow-up. Methods: All patients were referred to the pediatric nephrology clinic by pediatricians because of proteinuria. The study includes 74 patients (52 girls, 22 boys) with a mean age of 13.15 +/- 2.32 and records the presenting symptoms, degree of proteinuria, and radiologic findings. The diameter ratios of the left renal vein before and after stenosis and peak systolic velocity (PSV) ratios were calculated with a Doppler ultrasound, with a peak systolic ratio of 3.0:1 or greater was accepted as the diagnostic criterion for NS. Results: The mean age was 13.15 +/- 2.32 (5.33-17.42) years, while the mean follow-up duration was 14.6 +/- 9.1 months. Proteinuria was not correlated with the degree of compression. Most patients had a good prognosis, and none of them required medical or surgical treatment. A significant reduction or complete normalization of proteinuria was seen in more than half of the patients under conservative management. Conclusions: Based on our findings, NS seems to have a good prognosis in children who present with isolated proteinuria.