Small‐fiber neuropathy associated with autoinflammatory syndromes in children and adolescents

Introduction Small‐fiber neuropathy is rare in children. It has been associated with several autoimmune disorders, but there are no reports of an autoinflammatory etiology. Methods The data of four children/adolescents presenting with erythromelalgia and neuropathic pain from 2014 to 2019 were collected retrospectively from the electronic database of a pediatric medical center. Results Results of clinical and/or electrophysiological evaluation excluded large nerve fiber involvement. Skin biopsy results confirmed small‐fiber neuropathy. According to genetic analysis, two patients were heterozygous and one was homozygous for mutations in the familial Mediterranean fever (MEFV) gene. Behcet disease was diagnosed in the fourth patient. Treatment with anti–interleukin‐1 agents, intravenous immunoglobulin, and glucocorticoids was beneficial. Discussion The diagnosis of small‐fiber neuropathy should be considered in children/adolescents presenting with erythromelalgia. A thorough investigation is required to reveal the underlying disorder. Clinicians should be alert to the peripheral neurological manifestations of autoinflammatory syndromes because effective treatments are available.