RESUMO
Vascular complications are frequently associated with SLE. It is hypothesized that haemorrheological abnormalities may play a role in the aetiology of micro-and-macrocirculatory disorders in SLE. The range of rheological abnormality was determined by measuring the concentration of plasma fibrinogen, serum albumin and relating these abnormalities to change in relative plasma viscosity (RPV) and relative serum viscosity (RSV) in 21 SLE patients. The SLE disease activity index (SLEDAI) was used to define the severity of the disease. Eleven patients were "severe" (SLEDAI score> 12) and ten patients were "limited" (SLEDAI score< 12). RPV and RSV were measured by capillary viscometry. Plasma fibrinogen was determined by a clot-weight procedure and serum albumin and globulin by the Biuret method. Results from the SLE patients were compared with those from a randomly selected control group. A significant increase in RPV (p< 0.001) and RSV (p< 0.05) was recorded for the SLE patients. The patients with severe disease had a significant (p<0.001) increase in RSV but neither in fibrinogen nor RPV as compared with patients with limited disease activity. The increased viscosity in SLE patients may constitute an impediment in blood flow. Furthermore, the higher serum viscosity in patients with severe disease suggests that serum viscosity may provide a useful marker for disease activity. (AU)
