Neonatal Myasthenia Gravis in the Infant of an Asymptomatic Thymectomized Mother

Abstract

SUMMARY:A case of neonatal myasthenia gravis is reported in the infant of an asymptomatic thymectomized mother with comparably elevated acetylcholine receptor (AChR) antibody titers. The mother remained asymptomatic despite elevated antibody titers while the infant became asymptomatic in association with the disappearance of the AChR antibody. It is suggested that the AChR antibody plays an essential role in the development of neonatal myasthenia gravis. It is also suggested that a thymic factor is necessary for the development of clinical symptomatology accounting for the lack of correlation between the clinical state of the mother and infant.

Myasthenia gravis with polyhydramnios in the fetus of an asymptomatic mother

“…This may be explained by the well-known lack of a relation between antibody titres and symptoms in adults. Two cases have been reported of neonatal MG in infants born to mothers who were in remission at the time of delivery, one of whom had been thymectomized, but had high antibody titres (Elias et al, 1979;Olanow et al, 1982). These cases clearly reflect the difference in response between the mother and infant.…”

“…Transient neonatal myasthenia gravis (MG) occurs in about 1&20 per cent of infants born to mothers with this disorder (PlauchC, 1991;Papazian, 1992). Neonatal disease does not appear to correlate with the severity of maternal symptoms and may exceptionally occur in previously treated patients in remission at the time of delivery (Elias et al, 1979;Olanow et al, 1982). Severe cases of neonatal MG may be expressed prenatally as arthrogryposis (Stoll et al, 1991) or polyhydramnios (Morel et al, 1984).…”