[Pre-evening meal administration of tacrolimus improved refractory ocular symptoms in two young children with latent general myasthenia gravis].

We report two patients with latent general myasthenia gravis (MG) with refractory ocular symptoms who were successfully treated with pre-evening meal administration of tacrolimus. Patient 1 was a 4-year-old girl with persistent ocular symptoms despite high-dose steroid therapy and thymectomy. Oral tacrolimus was initiated at the age of 3 years, which was resulted in complete resolution of symptoms. After one year, hemilateral ptosis recurred. The plasma consentration of tacrolimus was very low, probably due to sudden weight gain. Increasing the dose and a change from post- to pre-evening meal administration of tacrolimus enabled maintenance of its concentration and complete control of ocular symptoms. Patient 2 was a 2-year-old boy whose symptoms were refractory to steroid therapy after his first relapse. Since post-meal administration of tacrolimus provided partial benefit, the closing schedule was changed to pre-evening meal administration, with good results. Neither patient had adverse effects of tacrolimus. It is difficult to maintain an effective tacrolimus concentration in children due to marked growth and rapid metabolic rates. Pre-evening meal administration of tacrolimus is an easy, safe and useful method of treatment in MG young children.