Levamisole therapy in children with frequently relapsing and steroid-dependent nephrotic syndrome: a single-center experience.

INTRODUCTION: Numerous studies suggest that levamisole, an antihelmintic agent with an immunomodulatory effect, reduces the number of relapses in children with frequently relapsing and steroid-dependent nephrotic syndrome (FRNS/SDNS). The aim of the study was to present a single center's experience in treatment of FRNS and SDNS with levamisole.

MATERIAL AND METHODS: Among 72 children with FRNS/SDNS treated in our department with levamisole in the years 1984-2011 we studied in detail 53 patients (mean age: 6.5 ±3.0 years), in whom the medication was administered for at least 6 months. In these 53 patients we evaluated: the course of the disease before levamisole, the renal biopsy result, medications used, prednisone dose on levamisole initiation, duration of levamisole treatment, time to first relapse and number of relapses on levamisole, and levamisole side effects.

RESULTS: The duration of nephrotic syndrome was 3.4 ±2.9 years, and the number of relapses before levamisole treatment was 6.0 ±3.4. The dose of prednisone on initiation of levamisole treatment was 1.2 ±0.6 mg/kg/24 h, and the duration of levamisole treatment was 15.0 ±7.3 months. During levamisole treatment proteinuria relapsed in 34/53 (64.2%) children, and the time to first relapse was 8.8 ±8.1 months. During levamisole therapy relapses of the disease decreased significantly (2.7 ±2.0 vs. 1.8 ±2.1 relapses/year, p = 0.02). Time to first relapse correlated with total number of relapses (R = -0.59, p < 0.001) and number of relapses in one year during levamisole treatment (R = -0.60, p < 0.001).

CONCLUSIONS: Levamisole is effective in reducing the number of relapses in children with frequently relapsing and steroid-dependent nephrotic syndrome. Early relapse of proteinuria on levamisole treatment in children with FRNS/SDNS suggests low efficacy of further treatment.