Transient Neonatal Myasthenia Gravis: A Case Report

Area of Science:

• Neonatal Medicine
• Neurology
• Immunology

Background:

• Myasthenia gravis (MG) in neonates is typically caused by maternally transferred antibodies to the acetylcholine receptor (AChR).
• This condition affects 10%-15% of infants born to mothers with MG, leading to impaired neuromuscular transmission.
• Neonatal intensive care unit (NICU) admission is common for affected newborns due to feeding and respiratory issues.

Observation:

• A male newborn presented with feeding difficulties, choking, generalized hypotonia, and facial weakness shortly after birth.
• Physical examination revealed a weak cry, inability to close eyelids, and poor sucking and swallowing reflexes.
• Laboratory tests confirmed elevated anti-acetylcholine receptor antibody levels (36.30 nmol/L).

Findings:

• The diagnosis of transient neonatal myasthenia gravis (TNMG) was established based on maternal history and clinical presentation.
• Treatment involved anticholinesterase agents and intravenous immunoglobulin (IVIg) therapy.
• The infant showed progressive clinical improvement, allowing for discontinuation of anticholinesterase agents by day 31.

Implications:

• A maternal history of MG and characteristic infant symptoms are often sufficient for diagnosing TNMG.
• Early diagnosis and management, including anticholinesterase agents and IVIg, are crucial for favorable outcomes.
• Most infants with TNMG experience spontaneous remission within weeks to months, highlighting the importance of timely intervention.