Add-on therapy with montelukast in the treatment of Henoch-Schönlein purpura.

Previous studies suggested that leukotrienes (LT) were involved in the pathogenesis of Henoch-Schönlein purpura (HSP). This study investigated the efficacy of an add-on therapy with montelukast in the treatment of HSP. In this four-center, double-blind, placebo-controlled, parallel paired comparative study, 130 children with HSP were divided into two large groups: 84 patients without nephritis and 46 patients with nephritis. For each pair of patients with the same severity of disease, one subject was randomly allocated to one subgroup and the other allocated to the other subbroup; one subgroup received routine treatment plus placebo treatment, while the other subgroup received routine treatment plus montelukast treatment for 3 months. The efficacy was determined using Severity Scale Score (SSS). Blood eosinophil count, eosinophil cationic protein (ECP), IgE, interleukin (IL)-4, IL-5, IL-6, IL-8, IL-17, LTB4 , and urinary LTE4 were measured. Add-on therapy with montelukast alleviated the symptoms of HSP including purpura, abdominal pain, stool occult blood, arthritis, proteinuria and hematuria, and, accordingly, shortened the length of hospital stay, and lowered blood eosinophil count, ECP, IgE, IL-4, IL-5, IL-6, IL-8, IL-17, LTB4 , and urinary LTE4 production, and also lowered the HSP relapse rate during the 3 months of treatment, but did not alter the outcome of nephritis at the end of follow up. Add-on therapy with montelukast alleviated the symptoms of HSP. HSP may be improved by add-on therapy with a leukotriene receptor antagonist.