Isaacs’ syndrome in pregnancy

Isaacs’ syndrome is a rare neuromuscular disorder of continuous muscle fibre activity resulting from peripheral nerve hyperexcitability. Symptoms commonly include myokymia (muscle twitching at rest), pseudomyotonia (delayed muscle relaxation), muscle cramps and stiffness. It is caused by voltage-gated potassium channel dysfunction and may be inherited or acquired. Treatment commonly includes anticonvulsants, immunosuppressive therapy and plasma exchange. To date only two cases of Isaacs’ syndrome in pregnancy have been reported. We present a case of maternal Isaacs’ along with a review of the literature. There are few reports of Isaacs’ syndrome in pregnancy, but all are associated with favourable outcomes. Given the autosomal dominant inheritance pattern, genetic counselling of the gravida is recommended. Anticonvulsant may have to be used in pregnancy, and given the potential teratogenicity with several of these agents; preference should be given to newer drugs such as lamotrigine.