Differentiating Autonomic Denervation Dermatitis From Post-traumatic Eczema: A Case Series of Localized Eczematous Eruptions.

Autonomic denervation dermatitis is a newly introduced term that describes the occurrence of a scaly eczematous lesion at the site of incision of a previous surgery. The time lag between the incision and the occurrence of the eczematous lesion varies greatly, ranging from months to years. Autonomic denervation dermatitis, by definition, can occur at any site of previous surgery; however, a few sites are specially named, like surgery of the knee, injury to the infrapatellar branch of the saphenous nerve, and traumatic eczematous dermatitis (SKINTED) occurring after total knee arthroplasty. Autonomic denervation dermatitis is believed to occur due to the transection of dermal nerves, which pathophysiologically differentiates it from post-traumatic eczema, an inflammatory reaction presenting as eczematous lesions that develop at and around sites of mechanical, thermal, or chemical injury. Herein, we describe a series of five such cases and try to differentiate between autonomic denervation dermatitis and post-traumatic eczema.