Lymphorrhage localized to the muscle end-plate in myasthenia gravis

Lymphocytic infiltration of muscle (lymphorrhage) is occasionally observed in myasthenia gravis. We describe a 56-year-old woman with autoimmune myasthenia gravis, whose muscle biopsy specimen demonstrates acute cellular reaction localized to the end-plate region. This observation raises the possibility of a more direct role of the cellular immune system in the pathogenesis of the disease, and provides a morphologic link between the human and the experimental myasthenia gravis.