An Egyptian child with erythromelalgia responding to a new line of treatment: a case report and review of the literature
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.