Prothrombotic state in HIV: A study on protein C, protein S, homocysteine and correlation with CD4 counts

Human immunodeficiency virus (HIV) may result in variable haematological manifestations. Thrombotic events are more common among HIV-infected persons than the general population, possibly due to the increased inflammatory/hypercoagulable state and presence of concurrent comorbidities.

(1) Screen for coagulation abnormalities in HIV-infected patients. (2) Detect certain prothrombotic factors such as deficiency of protein C and protein S and elevation of homocysteine as possible precursors of coagulation defects in HIV patients. (3) Correlation of coagulation abnormalities with CD4 counts.

A pilot study of 1-year duration conducted in the Department of Pathology in collaboration with ART centre, KGMU Lucknow. All diagnosed HIV-seropositive patients (n = 30) who were not taking Vitamin K, antithrombotic and antiplatelet drugs including aspirin, oral contraceptives and not having known protein C/S deficiency were included in the present study as cases. Apart from this, 30 age- and sex-matched healthy individuals were also included in the present study. Assessment of the bleeding time, prothrombin time and activated partial thromboplastin time, complete blood count was done. Protein C and S were measured by calorimetric assay. Serum homocysteine was measured by the semi-automated method. CD4 count was done by flow cytometry.

The findings of the present study suggest a relationship between HIV, its complications and thrombosis. The HIV-seropositive patients have reduced levels of haemoglobin, CD4 counts, platelet counts, mean platelet volume, protein C and S activity as compared to the healthy individuals. Thrombophilic abnormality in the form of hyperhomocysteinaemia is more frequent in HIV-infected patients. All these parameters have a definite correlation with CD4 count.