Cutaneous findings of collagen vascular disease and related emergent complications

Collagen vascular diseases are disorders of unknown etiology, with features of autoimmunity, in which the immune system loses the capacity to distinguish self from nonself. This loss of immune tolerance can result in varied and protean clinical manifestations, ranging from mild constitutional symptoms to major organ failure. Skin changes may be the initial manifestation of, or have pathognomonic features, for specific collagen vascular diseases, and are often invaluable to diagnosis. In this chapter we focus on identifying features of collagen vascular diseases, with an emphasis on cutaneous findings and emergent complications.