Leflunomide treatment in juvenile idiopathic arthritis

Juvenile idiopathic arthritis is the most common chronic rheumatic disease of childhood resulting in disability in untreated cases. Disease modifying anti-rheumatic drugs form the first-line treatment in JIA. However, the data about leflunomide (LFN) in treatment of JIA is limited. We reviewed the medical files of JIA patients who were followed-up regularly and had received LFN. A total of 38 patients were included to the study. Among them, 24 had oligoarticular JIA, eleven had polyarticular JIA, two had ERA and one had psoriatic arthritis. 36 were initially treated with methotrexate and two patients diagnosed with ERA were treated with sulfasalazine. Sulfasalazine treatment was switched to LFN due to inadequate response at the 3rd month of therapy. Methotrexate was ceased due to gastrointestinal intolerance in 36 patients. Of these 36 patients, 19 patients had either low disease activity (n = 13) or remission (n = 6). LFN was administered to 13 patients with low disease activity. During the follow-up of the six patients in remission, relapse ensued and LFN treatment was started. The remaining 17 patients had moderate (n = 10) or high (n = 7) disease activity requiring biologic agents. But due to inadequate response to biologic agents, LFN was added to the therapy. All of the patients were clinically inactive at the last visit. Only two adverse events resolving within 2 weeks were noted (Lymphopenia = 1, elevated liver enzymes = 1). LFN may be an alternative therapy in case of MTX intolerance or toxicity.