Transient neonatal myasthenia gravis revealing a myasthenia gravis and a systemic lupus erythematosus in the mother: case report and review of the literature.

Transient neonatal myasthenia gravis (TNMG) and neonatal lupus are rare conditions due to the transplacental passage of antibodies. We describe a unique case of TNMG, revealing a myasthenia gravis (MG) associated with systemic lupus erythematosus (SLE) in the mother. J. M., 8 days of age, was admitted for jaundice. Examination revealed poor sucking, facial weakness, and hypotonicity. TNMG was confirmed with a high level of antiacetylcholine receptor antibodies in the infant and his mother. No sign of neonatal lupus was observed. Clinical recovery was obtained. The elder brother had autism. In case of previous maternal MG, a low percentage of infants develop TNMG (10 to 20%), but monitoring is required at birth. Improvement is usually obtained within 3 weeks. No correlation has been found between maternal symptoms, antibodies titer, and signs of TNMG. Most cases of neonatal lupus are associated with positive anti-SSA/SSB antibodies in the mother. Both conditions, MG and SLE, are reported, but pregnancies are very few. Autism in the brother focuses on its relationship with immune diseases.