Evaluation of the Modified Wells Score in predicting Venous Thromboembolic disease (VTE) in patients with Tuberculosis (TB) or Human Immunodeficiency Virus (HIV) in a South African (SA) setting
Background There is paucity of data on the Modified Wells Score (MWS) utility on patients with venous thromboembolism (VTE) in a South African setting where there is a high burden of Human immunodeficiency virus (HIV) and Tuberculosis (TB). This study analyses the performance of this score in HIV/TB infected patients compared to non-infected patients. Objectives Assess the performance of the MWS as an additional risk factor for VTE in hospitalised patients with a high burden of HIV/TB infections. Methods A retrospective cross sectional cohort analysis of the utility of the MWS in 156 HIV/TB infected and non-infected adult patients diagnosed with VTE on Compression Ultrasonography (CUS) or Computed Tomography Pulmonary Angiography (CTPA) in a medical inpatient setting over six months. Patients with HIV and/or TB were assessed as having an additional risk factor (1 point for each) and this was compared to the MWS. A McNeymar!s paired sample chi- squared test was used to compare the sensitivity of this score against the MWS. Results Of the 156 patients with VTE who were enrolled, HIV was the commonest risk factor (42.31%) with TB accounting for 10.90% of cases. When the MWS adjusted for HIV/TB was used, the sensitivity increased from 25% to 100% for the HIV-/TB+ category, it increased from 77.36% to 98.11% in the HIV+/TB- category and increased from 84.62% to 92.95% in the HIV+/TB+ category. These differences were statistically significant at pvalue <0.05 in all categories. Conclusion The MWS performs better when HIV/TB infectivity are included as additional risk factors in the score.
A research report submitted in partial fulfilment of the requirements for the degree of Master of Medicine in Internal Medicine to the faculty of Health Sciences, School of Clinical Medicine, University of theWitwatersrand, Johannesburg 2022