Prenatal immunomodulation treatment in neonatal myasthenia gravis.

Neonatal mysthenia gravis (NMG) is a rare cause of arthrogryposis multiplex congenita (AMC) due to diaplacental transfer of maternal acetylcholine receptors (AChR) antibodies. 2 cases of severe NMG complicated by chronic lung disease and pulmonary arterial hypertension are reported. With respect to the severe course of the index patient, prenatal diagnosis and immunomodulation treatment were offered during the 2nd pregnancy. The combination of prenatal immunoadsorption (IA) therapy, administration of intravenous immunoglobulin (IVIG) and prednisolone failed. Failure may be partly explained by immaturity of the infant. However, considering the successful treatment of fetal/neonatal alloimmune thrombocytopenia (AIT) reported in literature, a treatment approach with IVIG doses up to 1-2 g/kg per week plus prednisone/prednisolone at a higher dose up to 1 mg/kg/d might be more effective.