Pediatric Myasthenia Gravis: A Review

Abstract

Myasthenia gravis refers to a group of diseases affecting the neuromuscular junction resulting in muscle weakness. The clinical hallmark of this condition is skeletal muscle weakness that worsens with sustained or repetitive muscle activation, caused via disruption of neuromuscular transmission by antibodies directed most commonly against the nicotinic acetylcholine receptor. Transient neonatal myasthenia gravis is caused by the crossing of antibodies from a myasthenic mother to her developing child, while juvenile myasthenia gravis involves the production of antibodies by the child's own immune system against neuromuscular junction components. Ptosis and extraocular muscle weakness are common presenting symptoms of juvenile myasthenia gravis and may be accompanied by, or progress to, generalized weakness. Diagnosis of myasthenia gravis relies on careful neurological examination, supported by additional diagnostic modalities which may include the patient's response to short-acting cholinesterase inhibitors, serum testing for causative antibodies, or electromyography. Management options include cholinesterase inhibitors for symptomatic treatment, immunosuppression with corticosteroids or steroid-sparing immunosuppressants, and thymectomy when a thymoma is identified on imaging.