Neuromyotonia: a skin-deep problem

Abstract

A 45-year-old woman was evaluated for right-sided hemicorporal scar-like skin lesions on her arm and thoracic and inguinal areas that appeared shortly after reduction mammoplasty. Five years later, she developed spontaneous cramps and involuntary abnormal, painful, twitching movements in the same areas. With time, the cramps worsened and disabled the patient. The use of her right arm triggered contractures of muscles and abnormal movements. A diagnosis of neuromyotonia (NMT) was established on the basis of clinical findings and on electromyographic findings of a burst of high-frequency motor unit potentials recorded in the right triceps in the area of skin lesions. The results of medullary, encephalic MRI as well as a comprehensive metabolic panel were normal. She was positive for antinuclear antibodies without specificity. Neither antineural antibodies nor antivoltage-gated potassium channel complex antibodies (specifically, leucine-rich glioma inactivated protein 1 and contactin-associated protein-like-2) were detected. Her skin lesions were diagnosed as morphea. Two combined strategies of treatment were initiated: antiepileptic drugs for NMT and corticosteroids and methotrexate for morphea. NMT is a rare, debilitating neurological complication of morphea.