Neuropathic pruritus (itch) in neuromyelitis optica

Abstract

Background: Neuropathic pruritus (itch) is an uncommon, but well described, symptom in neurology. There are itch-specific neurons in the dorsal horn of the spinal cord. We noted excessive pruritus in patients with neuromyelitis optica (NMO). Objective: We aimed to explore the characteristics of pruritus in NMO patients. Methods: We reviewed case records of a well-defined cohort of 45 serial aquaporin-4 antibody-positive patients visiting the national NMO service. All patients were interviewed. Results: Of the 45 antibody-positive NMO patients, 44 had myelitis and 12 of those 44 (27.3%) patients reported pruritus within a week of other symptoms of transverse myelitis with central cord involvement. In three patients, pruritus was the first symptom of a relapse, while in one case, pruritus was the very first symptom of the index episode of NMO. Conclusion: Neuropathic pruritus seems to be a common, but under-recognised symptom of myelitis associated with NMO.