Evaluation of oral iron treatment in pediatric restless legs syndrome (RLS).
We conducted a retrospective chart review of children with restless legs syndrome (RLS) to evaluate the efficacy of oral iron treatment, which was administered open-label during the course of clinical care. In addition, we provided detailed clinical information about RLS in this pediatric cohort. The study included 30 consecutive Japanese children with RLS who visited the Pediatric Sleep Clinic at Osaka University Hospital, and consisted of 17 boys and 13 girls, aged 2-14 years (mean ± SD, 6.5 ± 2.8). All-night polysomnography was performed in 18 patients and serum ferritin levels were measured in all the patients. After the diagnosis of RLS, iron was administered at doses between 1.6 and 7.8 mg/kg/day (3.2 ± 1.3). Serum ferritin was re-evaluated 3-6 months after iron treatment, or when RLS symptoms had disappeared. The patient age at onset of RLS symptoms ranged from six months to 13 years (4.3 ± 3.6). A positive family history was recognized in 19 children (63.3%). Serum ferritin levels before therapy were 9-62 ng/ml (26.6 ± 12.8) and oral iron supplementation was reported to be highly effective in 17 children, effective in 10, and ineffective in three. The serum ferritin level at follow-up was 23-182 ng/ml (83.5 ± 49.8). The onset of treatment effect was within approximately three months. Iron treatment could be effective in Japanese pediatric RLS.