Activation of coagulation and fibrinolysis in HIV-infected patients

Various coagulation abnormalities were reported in HIV-infected patients, which were usually considered as risk factors for thrombosis in the general population or in other disease states. This study was undertaken to determine whether HIV-infection was associated with an on-going pre/prothrombotic state. For that purpose, 70 consecutive HIV-infected out-patients were evaluated at distance of any acute episode. (55 males and 15 females with a mean age of 34 years, range: 19–69). 29 patients (41%) with a CD4+ lymphocytes count below 200 × 10⁶/L were classified as having AIDS. The control group consisted of 33 age and sex-matched healthy individuals. The plasma levels of sensitive markers of thrombin generation (prothrombin fragment 1+2 and thrombin-antithrombin complex), plasmin generation (plasmin-plasmin inhibitor complex), and plasmin activity (fibrin degradation products) were measured using ELISAs. The plasma level of these markers were significantly higher in HIV-infected patients than in healthy HIV-negative controls. Moreover, the plasma levels of these markers were found to be highly significantly correlated (p<0.001) in the patients group, suggesting an increased activation of both coagulation and fibrinolysis. However, despite trends toward increasing levels with decreasing CD4+ lymphocyte count, the plasma levels of these markers were not significantly different in AIDS and in non AIDS patients (classified upon the CD4+ lymphocytes count below and above 200 × 10⁶/L). These results suggest that HIV-infection is associated with an activation of both the coagulation and fibrinolytic systems, which could lead to a prothrombotic state in some of the patients.