Isaacs’ Syndrome (Acquired Neuromyotonia): A Case Report

We report a case of a 24-year-old male, laborer by profession, who consulted neurology outpatient with chronic symptoms of gross muscle contractions, generalized weakness, and limitation in his routine activities since the age of eight. The examination was remarkable for pseudo hypertrophy in the calves muscles, pes cavus, and gross spontaneous muscle fasciculation with symmetrical involvement of the distal and proximal muscle groups in lower and upper extremities. His creatinine phosphate kinase (CPK) levels in blood were high. Nerve conduction study (NCS) and electromyography (EMG) confirmed diagnosis of Issacs’ disease showing neuromyotonic discharges associated with denervation and polyphasic units with fibrillation, positive sharp waves, and continuous repetitive discharges. He was started on carbamazepine, to which he responded well, and his symptoms improved.