Blood hyperviscosity with reduced skin blood flow in scleroderma

Abstract

SUMMARY The vascular complications of scleroderma have previously been attributed to the progressive obliteration of small vessels. Our study was carried out to determine whether abnormalities of blood viscosity occur in this disease, thereby contributing to th-ischaemic process. Blood viscosity was measured in 20 patients using a rotational viscometer. At a high rate of shear, blood hyperviscosity was found in 35 % of the patients and at a low rate of shear, in 70 %. In addition there was a significant increase in the plasma viscosity which implicates changes in plasma proteins (fibrinogen, immunoglobulins) as causing the hyperviscosity. Measurement of the hand blood flow by venous occlusion plethysmography showed reduced flow at 320, 270, and 20°C. A unique finding was a delayed recovery of the blood flow after cooling. These observations suggest that the increased resistance to blood flow in skin affected by scleroderma may be caused by an interaction between the occlusive vascular lesion and blood hyperviscosity. In addition, blood flow patterns and hyperviscosity could help distinguish scleroderma from primary Raynaud's disease.In patients with scleroderma several of the clinical features, such as Raynaud's phenomenon, can be attributed to a reduced blood flow through small arteries, arterioles, and capillaries. Histological and radiological studies have confirmed the existence of vascular abnormalities in this disease (Soila, 1964;Norton and Nardo, 1970;Rodnan, 1972;Campbell and LeRoy;1975), although the cause of these changes is unknown. Since the resistance to blood flow is partly dependent on the blood viscosity, detailed studies were carried out to determine whether blood hyperviscosity exists in patients with scleroderma, thereby contributing to the already increased vascular resistance associated with narrowing of the vessel lumen. The degree of impairment of the skin blood flow in this group of patients was assessed by measuring hand blood flow and its response to cooling. We compared the results with those obtained in patients with other connective tissue diseases and with impaired peripheral circulation. PatientsTwenty patients with scleroderma were studied.

Successful long-term (22 year) treatment of limited scleroderma using therapeutic plasma exchange: Is blood rheology the key?

“…Research studies [11,12,13,14,15] have consistently shown elevated blood viscosity in the majority of systemic scleroderma patients. The specific factor contributing to hyperviscosity, when reported, is increased red blood cell (RBC) aggregation.…”

Systemic Sclerosis - a Microvascular Disorder?

“…Increased viscosity of the blood occurs in SS (Goyle & Dormandy 1976, McGrath et al 1977, particularly at low shear rates and low temperatures as in the periphery, and may be due to reduced red cell deformability or to elevated fibrinogen levels. .…”

Raynaud's syndrome.

“…This picture may be confused with that of ulcerative colitis. 9 Diagnosis may sometimes be difficult: salmonella enteritis and ulcerative colitis are both common and their sigmoidoscopic appearances are similar. If the colitis is treated with corticosteroids then simultaneous systemic antibiotic cover is essential.…”