Comparison of pathological clotting using haematological, functional and morphological investigations in HIV-infected and HIV-uninfected patients with deep vein thrombosis
Abstract Background Patients infected with the human immunodeficiency virus (HIV) are more prone to systemic inflammation and pathological clotting, and many may develop deep vein thrombosis (DVT) as a result of this dysregulated inflammatory profile. Coagulation tests are not routinely performed unless there is a specific reason. Methods We recruited ten healthy control subjects, 35 HIV negative patients with deep vein thrombosis (HIV negative-DVT), and 13 HIV patients with DVT (HIV positive-DVT) on the primary antiretroviral therapy (ARV) regimen- Emtricitabine, Tenofovir and Efavirenz. Serum inflammatory markers, haematological results, viscoelastic properties (using thromboelastography-TEG) and scanning electron microscopy (SEM) of whole blood (WB) were used to compare the groups. Results DVT patients (HIV positive and HIV negative) have raised inflammatory markers. The HIV positive-DVT group has anaemia in keeping with anaemia of chronic disorders. DVT patients have a hypercoagulable profile on the TEG but no significant difference between HIV negative-DVT and HIV positive-DVT groups. The TEG analysis compared well and supported our ultrastructural results. Scanning electron microscopy of DVT patient’s red blood cells (RBCs) and platelets demonstrates inflammatory changes including abnormal cell shapes, irregular membranes and microparticle formation. All the ultrastructural changes were more prominent in the HIV positive-DVT patients. Conclusions It is well-known that HIV infection is linked to inflammation and inflammation is linked with the presence of a hypercoagulable state. The presence of DVT is also associated with inflammation. Whether HIV is the cause of the DVT is not certain. Although there were trends that HIV infected patients were more hypercoagulable on functional tests (viscoelastic profile) compared to HIV uninfected patients, there were no significant differences between the 2 groups. Morphologically there were inflammatory changes in patients with DVT. These ultrastructural changes, specifically with regard to platelets, appear more pronounced in HIV infected patients which may contribute to increased risk for hypercoagulability and deep vein thrombosis.