Abstract
One of the etiological factors in Raynaud's phenomenon in connective tissue disease is the increase in plasma viscosity. We examined the efficacy of plasmapheresis (PP) as an index of blood and plasma viscosity. We performed double filtration plasmapheresis on 6 patients with connective tissue disease exhibiting Raynaud's phenomenon, who we diagnosed as one case of systemic lupus erythematosus and dermatomyositis, two cases of progressive systemic sclerosis and mixed connective tissue disease. We measured blood and plasma viscosity before and after PP. Blood viscosity was measured by a cone-plate rotational viscometer (Wells-Brookfield, Inc.). Plasma viscosity was measured by a capillary viscometer (Isogai's method). We studied the clinical symptoms of Raynaud's phenomenon, and measured the digital temperature by thermography. No significant difference in blood viscosity was found. Plasma viscosity in patient with Raynaud's phenomenon was higher than in normal controls, and significantly decreased after PP. The digital temperature by thermography tend to rise after PP. We noted an improvement in clinical symptoms by PP. We therfore conclude that PP is a useful way to treat of Raynaud's syndrome.
