Myasthenia gravis patients with anti-MuSK antibodies.

In myasthenia gravis (MG) patients without detectable anti-acetylcholine receptor (anti-AChR) antibody, referred to as seronegative myasthenia gravis patients, there is a variable proportion of patients with antibodies against the muscle-specific kinase (MuSK). MuSK antibodies were found in 8 (29.6%) of our 27 patients with generalized MG without anti-AChR antibodies. All these patients were female. The age at the onset ranged from 22 to 38 years. All patients had ocular and bulbar symptoms, and two patients also had generalized limb weakness. Two patients had pure ocular symptoms for 7 or 8 years before the development of bulbar symptoms. All anti-MuSK positive patients were treated with immunosuppressive drugs, three received plasmapheresis and one patient required mechanical ventilation. Our results are consistent with other literature reports.

Myasthenia gravis in pregnancy: report on 69 cases.

OBJECTIVE: To review our experience with pregnancies in women with myasthenia gravis (MG). STUDY DESIGN: Sixty nine pregnancies among 65 women with MG patients managed by our department over 28 years were included. The course of the disease in pregnancy, mode of delivery and postpartal period were evaluated. RESULTS: One pregnancy miscarried. In 15% of patients the MG deteriorated in pregnancy a further 16% in the puerperium. 17% of pregnancies were delivered by cesarean section, one due to myasthenia exacerbation. All women with puerperal infections developed exacerbations. One neonatal death, not attributable to myasthenia, was recorded. Transitory neonatal myasthenia gravis (TNMG) was diagnosed in 30% infants. Its incidence was inversely associated with maternal disease duration (P < 0.05). Newborns of thymectomized mothers showed lower rate of neonatal myasthenia compared to those of non-thymectomized women (P < 0.05). CONCLUSIONS: MG patients can have normal pregnancy and delivery but the course is unpredictable. Shorter disease history and infection predispose to puerperal exacerbation. Maternal thymectomy lessens the likelihood of neonatal myasthenia. An interdisciplinary approach is required for managing the pregnant women with MG.