ACROCYANOSIS
Acrocyanosis is a bilateral dusky mottled discoloration of the hands, feet, and sometimes the face. It is persistent and accentuated by cold exposure. When the temperature is very low, the skin may be bright red. Trophic changes and pain do not occur, and pulses are present. This condition must be distinguished from Raynaud phenomenon , which is clearly episodic, often segmental, and painful, as well as from obstructive arterial disease .
Acrocyanosis is genetically determined and usually starts in adolescence. Chronic vasospasm of small cutaneous arterioles or venules with a secondary dilatation of the capillaries and subpapillary venous plexus has been postulated. Stasis in the papillary loops with aneurysmal dilatation at the tips redistributes blood flow to the subpapillary venous plexus. The blood flow may be compromised by altered erythrocyte flexibility, increased platelet adhesiveness, and other plasma viscosity factors.
Tissues are less sclerotic in acrocyanosis than in Raynaud phenomenon. They contain twisted collagen fibrils and large pericytes. In cases developing for the first time late in life, an underlying myeloproliferative disorder should be excluded. Remittent necrotizing acrocyanosis is associated with enhanced susceptibility to cooling and pain, as well as ulceration and gangrene of the fingers. Arteriolar occlusion by thrombi or intima proliferation may occur.
There is no effective treatment for acrocyanosis. Supportive measures to keep the skin warm are helpful.