Raynaud's phenomenon: Current concepts.

Raynaud's phenomenon (RP) is a transient, acral, vasospastic phenomenon that manifests with characteristic color changes. This vasospasm, classically triggered by cold temperatures, may also be driven by shifts in temperature, climate, or emotional state. Primary RP (PRP) is a common condition without severe sequelae. Secondary RP (SRP), which may be driven by vascular, autoimmune, hematologic, or endocrine etiologies, can result in digital ulceration, irreversible ischemia and necrosis, and secondary infection. This review delineates the clinical manifestations of both primary and secondary RP, as well as the current understanding of RP epidemiology and pathogenesis. Proper examination, including nailfold capillary microscopy, and laboratory workup for secondary causes of RP are also discussed. The traditional armamentarium of therapies used for RP, as well as newer medical and surgical options, is also summarized with particular regard to the clinical evidence for their efficacy.