Altered microrheological parameters in Raynaud's phenomenon

Raynaud's phenomenon is an episodic, painful attack of the acral parts caused by local diminished blood supply. The aim of our study was to examine hemorheological parameters, cold agglutinins, cryoglobulins and their relationship in patients suffering from Raynaud's phenomenon.Blood was taken from 74 patients (mean age: 48 years, female/male: 56/18). Cold agglutinins and cryoglobulins were determined. Hemorheological parameters were also measured such as hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability. Results were compared to a group of 58 healthy controls (mean age: 31.5 years, female/male: 24/34).Cold agglutinins were positive in 70%, cryoglobulins in 43% of patients. When compared to healthy controls, increased red blood cell aggregation (64.54  ±  8.93 vs. 61.11  ±  7.05) and decreased red blood cell deformability (0.669  ±  0.002 vs. 0.681  ±  0.001) was observed in Raynaud's patients (p < 0.05), but there were no differences in hematocrit (43.27% ± 3.85 vs. 44.10% ± 3.70), plasma (1.27 mPas ± 0.08 vs. 1.24 mPas ± 0.09) and whole blood viscosity (4.12 mPas ± 0.52 vs. 4.26 mPas ± 0.46). No differences were found between the hemorheological profile of cold agglutinin/cryoglobulin positive and negative patients. Also primary and secondary Raynaud's patients had similar rheological profile.Erythrocyte aggregation and deformability seems to be unfavorable in Raynaud's patients that can play a role in the disturbance of the microcirculation.