Juvenile and Neonatal Myasthenia Gravis

© 2014 Elsevier Inc. All rights reserved. Juvenile myasthenia gravis is rare compared to adult myasthenia gravis, but in some respects is a distinct subtype of this autoimmune neuromuscular disease. Prepubertal children are more likely to present with pure ocular symptoms and display a balanced gender ratio, whereas adolescents are more likely to develop generalized myasthenia gravis and to be female. The treatment options are similar in juvenile and adult myasthenia gravis; however, the risk-benefit calculations differ due to the particular vulnerabilities of the pediatric population. Steroids, which play an important role in the treatment of juvenile myasthenia gravis, may cause more lasting harm in children and adolescents compared to adults. Venous access for plasmapheresis is often more challenging in the pediatric setting, yet this therapeutic option should be considered whenever technically feasible. Neonatal myasthenia gravis is caused by transplacental transmission of acetylcholine receptor antibodies. Most affected infants require only respiratory and nutritional support and have excellent outcomes. By contrast, fetal-specific transfer of acetylcholine receptor antibodies can lead to arthrogryposis or other fetal acetylcholine receptor inactivation syndromes, associated with more significant long-term complications.