Neuromyotonia and myasthenia gravis without thymoma

Neuromyotonia is a syndrome characterised by motor unit hyperactivity leading to muscle cramps, fasciculations, muscle stiffness, and persistent muscle contraction. In most neuromyotonia patients, the disorder is acquired. An autoimmune or paraneoplastic origin is common.1–3 Myasthenia gravis, thyrotoxicosis, systemic sclerosis, inflammatory demyelinating neuropathies, thymoma, bronchial carcinoma, and small cell lung cancer may be associated. Here, we report a patient with neuromyotonia, associated with myasthenia gravis and anti-voltage-gated potassium channels (VGKC) and anti-acetylcholine receptor (AChR) antibodies without thymoma. A 58 year old man of Portuguese descent presented at our neuromuscular clinic with dysesthesia and hypesthesia in the first three fingers of the right hand. Symptoms had started nine years before and had been attributed to cervical radiculopathy. Over the years, the symptoms had been fluctuating but for the past two months they had become debilitating. Therefore, the patient sought a second opinion. The patient volunteered that, although right hand pain was his main complaint, for many …