A one year audit of patients with venous thromboembolism presenting to a tertiary hospital in Johannesburg, South Africa

Evaluation of the modified Wells score in predicting venous thromboembolic disease in patients with tuberculosis or HIV in a South African 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 HIV and tuberculosis (TB). This study analyses the performance of this score in HIV/TB-infected patients compared with non-infected patients.

Objectives

To assess the performance of the MWS as an additional risk factor for VTE in hospitalised patients with a high burden of HIV/TB infections.

Method

This study was 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 with 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 it increased from 84.62% to 92.95% in the HIV+/TB+ category. These differences were statistically significant at P < 0.05 in all categories.

Conclusion

The MWS performs better when the infectivity of HIV/TB is included as an additional risk factor in the score.

CT pulmonary angiography findings in HIV-infected patients referred for suspected pulmonary thrombo-embolic disease

Background

South Africa bares a significant burden of HIV and imaging is commonly performed as part of the workup for respiratory distress.

Objectives

The aim of this study was to document the prevalence of pulmonary thrombo-embolic disease (PTED) and other findings in HIV-infected patients referred for CT pulmonary angiography (CTPA) for suspected PTED.

Method

Forty CTPA studies of documented HIV-infected individuals investigated for suspected PTED during a 1-year period were retrieved, anonymised and interpreted by three consultant radiologists. Inter-reader reliability was calculated using Free Marginal multi-rater Kappa.

Results

Fourteen of the forty cases (35%) were positive for PTED. In the pulmonary embolism (PE)-positive group, 57.14% had peripheral disease and 42.86% had both peripheral and central disease. Associated findings in the PE-positive cases were pulmonary infarcts (17.5%), mosaic attenuation (17.5%) and linear atelectasis (7.5%). The most common incidental findings were solid pulmonary nodules (52.5%), non-wedge-shaped consolidation (45%), cardiomegaly (52.5%) and enlarged intra-thoracic lymph nodes (52.5%). Thirty per cent of the study population had findings related directly to the presence of PTED, whilst most cases in the study (77.5%) had pulmonary findings unrelated to PTED. In the PE-negative cases, 55% reported emergent findings that warranted immediate or urgent medical attention.

Conclusion

Computed tomography pulmonary angiography imaging is critical for diagnosing PE. However, further investigation into the judicious application of CTPA in HIV-infected patients with suspected PTED is required, as CTPA findings in most of the cases in this study were unrelated to PE.

Improving anticoagulation in sub-Saharan Africa: What are the challenges and how can we overcome them?

Patients in sub-Saharan Africa generally have poor anticoagulation control. We review the potential reasons for this poor control, as well as the potential solutions. Challenges include the affordability and centralisation of anticoagulation care, problems with access to medicines and international normalised ratio monitoring, the lack of locally validated standardized dosing protocols, and low levels of anticoagulation knowledge among healthcare workers and patients. Increasing numbers of patients will need anticoagulation in the future because of the increasing burden of noncommunicable disease in the region. We propose that locally developed "warfarin care bundles" which address multiple anticoagulation challenges in combination may be the most appropriate solution in this setting currently.

Pragmatic Recommendations for the Management of Anticoagulation and Venous Thrombotic Disease for Hospitalized Patients with COVID-19 in Low- and Middle-Income Countries

New studies of COVID–19 are constantly updating best practices in clinical care. Often, it is impractical to apply recommendations based on high-income country investigations to resource limited settings in low- and middle-income countries (LMICs). We present a set of pragmatic recommendations for the management of anticoagulation and thrombotic disease for hospitalized patients with COVID-19 in LMICs. In the absence of contraindications, we recommend prophylactic anticoagulation with either low molecular weight heparin (LMWH) or unfractionated heparin (UFH) for all hospitalized COVID-19 patients in LMICs. If available, we recommend LMWH over UFH for venous thromboembolism (VTE) prophylaxis to minimize risk to healthcare workers. We recommend against the use of aspirin for VTE prophylaxis in hospitalized COVID-19 and non–COVID-19 patients in LMICs. Because of limited evidence, we suggest against the use of “enhanced” or “intermediate” prophylaxis in COVID-19 patients in LMICs. Based on current available evidence, we recommend against the initiation of empiric therapeutic anticoagulation without clinical suspicion for VTE. If contraindications exist to chemical prophylaxis, we recommend mechanical prophylaxis with intermittent pneumatic compression (IPC) devices or graduated compression stockings (GCS) for hospitalized COVID-19 patients in LMICs. In LMICs, we recommend initiating therapeutic anticoagulation for hospitalized COVID-19 patients, in accordance with local clinical practice guidelines, if there is high clinical suspicion for VTE, even in the absence of testing. If available, we recommend LMWH over UFH or Direct oral anticoagulants for treatment of VTE in LMICs to minimize risk to healthcare workers. In LMIC settings where continuous intravenous UFH or LMWH are unavailable or not feasible to use, we recommend fixed dose heparin, adjusted to body weight, in hospitalized COVID-19 patients with high clinical suspicion of VTE. We suggest D-dimer measurement, if available and affordable, at the time of admission for risk stratification, or when clinical suspicion for VTE is high. For hospitalized COVID-19 patients in LMICs, based on current available evidence, we make no recommendation on the use of serial D-dimer monitoring for the initiation of therapeutic anticoagulation. For hospitalized COVID-19 patients in LMICs receiving intravenous therapeutic UFH, we recommend serial monitoring of partial thromboplastin time or anti-factor Xa level, based on local laboratory capabilities. For hospitalized COVID-19 patients in LMICs receiving LMWH, we suggest against serial monitoring of anti-factor Xa level. We suggest serial monitoring of platelet counts in patients receiving therapeutic anticoagulation for VTE, to assess risk of bleeding or development of heparin induced thrombocytopenia.

Prevention of Venous Thromboembolism in 2020 and Beyond

Venous thromboembolism (VTE) is the third most common cause of vascular mortality worldwide and comprises deep-vein thrombosis (DVT) and pulmonary embolism (PE). In this review, we discuss how an understanding of VTE epidemiology and the results of thromboprophylaxis trials have shaped the current approach to VTE prevention. We will discuss modern thromboprophylaxis as it pertains to genetic risk factors, exogenous hormonal therapies, pregnancy, surgery, medical hospitalization, cancer, and what is known thus far about VTE in COVID-19 infection.

A case series of venous thromboembolic disease in a semi-urban setting in Cameroon

Objective

Our goal was to study the clinical characteristics, risk factors and outcome of patients admitted for venous thromboembolism (VTE) in the medical unit of the Buea Regional Hospital, Cameroon between 1st July 2016 and 30th November 2017.

Results

Twenty-two patients were admitted for VTE. There were 12 (54.4%) men. The mean age was 54.9 ± 13.9 years (range: 31–77 years). The main risk factors were immobilization (40.9%), HIV infection (22.7%), tuberculosis (18.2%), obesity (13.6%) and cancer (13.6%). Nineteen (86.4%) patients had deep venous thrombosis (DVT), 3(13.6%) had pulmonary embolism (PE). One patient had a concomitant DVT and PE. All patients received low molecular weight heparin and 76.2% were discharged on oral vitamin K antagonist while 23.8% were discharged on direct oral anticoagulants. The median length of hospital stay was 9.5 days (range: 4–34). Three deaths (13.6%) were recorded. This study describes VTE in a semi-urban setting in Cameroon and shows that immobility, HIV infection and tuberculosis are common risk factors for VTE in this semi-urban setting.