Neuromyotonia: Remembering a Rare Pathology

Abstract

Neuromyotonia is an exceedingly rare disease. In most cases it seems to be acquired, with a probable autoimmune origin. It is characterized by peripheral nerve hyperexcitability with muscle hyperactivity and deficient relaxation, and it is frequently accompanied by autonomic and sensitive symptoms. The diagnosis is established by electromyography, showing spontaneous, multiple single motor unit discharges, firing at a high frequency. The diagnosis is relevant not only to achieve symptom control but also for its known association with neoplasia, which must be ruled out. Nevertheless, the diagnosis is difficult to establish due to the nonspecific and variable symptoms that may lead to confusion with the more common psychiatric or motor neuron diseases. Misdiagnose can result in incorrect therapeutic actions with further iatrogenic symptoms. We report a typical case of neuromyotonia, in respect of which we review the clinical presentation, complementary diagnostic methods, natural evolution and treatment of the disease.