Clinical characteristics and therapeutic evaluation of childhood myasthenia gravis.

ABSTRACT

This study aimed to analyze the clinical characteristics, classification and treatment of childhood myasthenia gravis (MG) and address the prognosis through follow-up. The clinical data of 135 children with MG were grouped according to clinical type and therapeutic drugs, retrospectively analyzed and prospectively monitored. Of the 135 MG patients, 85.2% had type I (ocular type), with only 4.2% progressing to systemic MG; 13.4% had type II (general type); and 1.5% had type III (fulminating type). Relapse occurred in 46.1% of the 102 patients that were followed up. The positive rate for the primary acetylcholine receptor antibody was 40.19%, without significant differences among clinical subtypes. The positive rate of the repetitive nerve stimulation frequency test by electromyography was 37.97%. Decreased expression of CD4+, CD8+, or CD3+ was present in 71% of the patients. Thymic hyperplasia was present in 5.93% of the patients, while 1.48% had thymoma. Steroid treatment was effective in the majority of the patients. Ocular type MG was common in this cohort of patients. The incidence and mortality of myasthenia crisis were low, the presence of concurrent thymoma was rare and only a limited number of children developed neurological sequelae.