Pediatric erythromelalgia: A retrospective review of 32 cases evaluated at Mayo Clinic over a 37-year period

Background: Erythromelalgia has not been well characterized in the pediatric population. Objective: We sought to review our experience of erythromelalgia in the pediatric age group. Methods: We conducted a retrospective review of patients 18 years of age and younger with a diagnosis of erythromelalgia who were examined at Mayo Clinic in Rochester, MN, from 1970 to 2007. Results: The records of 32 patients (girls, 22 [69%]) were evaluated. Mean age was 14.1 years (range, 5-18 years) and mean time to diagnosis was 5.2 years. Seven patients (22%) had a first-degree relative with erythromelalgia; 4 were from the same family. Physical activity was limited because of discomfort in 21 patients (66%) and school attendance was affected in 11 patients (34%). Noninvasive vascular studies, which compared temperature, laser Doppler flow, and transcutaneous oximetry in the toes, identified vascular abnormalities in 13 (93%) of 14 patients. Neurophysiologic studies with autonomic reflex screening (including quantitative sudomotor axon reflex test and thermoregulatory sweat testing) showed evidence of a small-fiber neuropathy involving the skin in 10 (59%) of 17 patients studied; there was no evidence of large-fiber neuropathy in 20 patients in whom electromyographic and nerve conduction studies were performed. Topical lidocaine was the most commonly prescribed treatment (44%). Fifteen patients were monitored for an average of 9.1 years (median, 5.0 years; range, 0.4-23.7 years). At last follow-up, 5 patients had stable disease, 4 showed improvement, two had resolution, one reported worsening of symptoms, and 3 had died (one suicide). Limitations: Conclusions are limited because this was a retrospective chart review. Conclusion: Erythromelalgia in pediatric patients is associated with substantial morbidity and even death. The majority of cases are not inherited. Most patients studied have associated small-fiber neuropathy. The disease course is variable. A reliable and safe treatment has not been determined.