Subcutaneous panniculitis like T cell lymphoma associated with erythromelalgia.

Erythromelalgia is a rare disorder that simulates a small fiber neuropathy and patients often have painful erythematous extremities during episodes. It is of two types: A primary or inherited form that is sometimes associated with a Na channel mutation or a secondary disorder associated with an underlying systemic disorder. We present a 19-year-old boy who presented to us with erythromelalgia and a febrile illness with systemic rash. Detailed work-up revealed another unusual condition: Subcutaneous panniculitis like T cell lymphoma (SPTCL). This is the first report of an association of erythromelalgia with SPTCL.