Although all newborn babies of myasthenia mothers have anti-AChR antibodies at birth, only a small percentage of them (10-15%) express the myasthenic syndrome. The myasthenic symptoms usually appear a few hours after birth and their average duration is about 3 weeks. The appearance of transient MG does not seem to be related to the severity of the mother's …show more content…
The majority, though not all. Of both myasthenic and non-myasthenic infants were found to have a repertoire of anti-AChR specificities very similar to their mothers. No significant differences were observed between sera from the two groups of mothers. The study was performed in an effort to explain why most infants of MG mothers do not exhibit MG symptoms, despite the presence of anti-AChR antibodies in their sera. An explanation might also be found for the discrepancies which are observed between antibody titre and disease severity among the adult MG patients. As far as it concerns the tested antigenic specificities of the anti-AChR antibodies, it was shown that: (1) the sera of the infants, whether myasthenic or not, have generally the same anti-AChR antigenic specificities as those of their mothers. Although the tested antigenic specificities were limited, the overall similarity between the sera of mothers and infants strongly suggests that passive transfer of anti-AChR antibodies in neonatal MG involves the whole or the major pan of their mothers" anti-AChR specificities; (2) The antigenic specificities of mothers who transfer the disease do not generally differ from those of mothers who do not