SECONDARY RAYNAUDS-PHENOMENON

Raynaud's phenomenon (RP) is an episodic digital ischemia provoked by internal and/or external stressors. While the primary RP occurs indepe ndently of other diseases and appears to be mediated by a vegetative d ysbalance of the peripheral vasomotor tone, the secondary RP is often part of an underlying disorder, especially of collagen-vascular diseas es such as SLE or scleroderma. Vascular involvement in the pathogenesi s of connective tissue diseases is well known but poorly understood. E ndothelium injury by autoantibodies and circulating immune complexes m ay play a central but not sufficient role in the pathogenesis of secon dary RP. In this review, epidemiology and diagnosis of RP secondary to connective tissues diseases are described and new pathogenic concepts are discussed in view of current knowledge on endothelial function.