Erythromelalgia: Definition, clinical contexts, differential diagnosis, and therapy. Single case and literature update

Clinical publications on this morbid condition report as many as 16 different Nav1 7 channel substitutions. They also report more than 40 pharmacological treatments, including agents with sodium channel blocking but nonspecific activity (mexiletine, lidocaine, carbamazepine), anti-neuropathic drugs (gabapentinoids and antidepressants), antidepressant drugs with efficacy on migraines (amitriptyline) vasoactive drugs for the management of hypertension, and analgesics (opioids and ketamine). Current research fails to address all patients’ clinical needs, although it recently suggests new genetic hypotheses yet to be tested and the central importance of genetic counseling, to inform patients and their families about the severity, likely course of symptoms, and risk of complications, and in some cases to guide clinical management. Current findings and the significant morbidity associated with the condition, even in light of the single case presented, highlight the need for mechanism-based therapies to improve clinical outcomes.