Commentary on 'Degos disease: a C5b-9/interferon-α-mediated endotheliopathy syndrome' by Magro et al: a reconsideration of Degos disease as hematologic or endothelial genetic disease.

Magro et al in April of 2011 published a new article in the American Journal of Clinical Pathology on the etiology and treatment of Degos Disease (DD), and importantly, its fatal variant malignant atrophic papulosis (MAP). Specifically, Magro noted that MAP is a disease involving the complement cascade that can be treated effectively with eculizumab. DD has two variants, a benign variant confined to the skin and a malignant (heretofore fatal) variant that involves the skin and systemic organs. Five aspects of DD are discussed: (1) the clinical findings of DD, (2) thrombosis and DD, (3) the histology of DD, (4) the presence of viral like inclusions in the endothelial cells of patients with DD, and (5) the lack of any apparent immune defect that relates to DD. It seems the previous criteria for Degos Disease must be amended. Paroxysmal nocturnal hemoglobinuria (PNH) is discussed and its relationship with DD explored. Eculizumab has been approved to treat paroxysmal nocturnal hemoglobinuria. A review of the data suggests that MAP is a hematological or endothelial disease like PNH. PNH, eculizumab, and data about DD is discussed to give a basis for understanding DD and speculate why eculizumab may be promising for the treatment of MAP.