Clinical presentation and diagnostic work up of suspected pulmonary embolism in a district hospital emergency centre serving a high HIV/TB burden population

Abstract

IntroductionThe diagnosis of pulmonary embolism (PE) is challenging to make and is often missed in the emergency centre. The diagnostic work-up of PE has been improved by the use of clinical decision rules (CDRs) and CT pulmonary angiography (CTPA) in high-income countries. CDRs have not been validated in the South African environment where HIV and tuberculosis (TB) are highly prevalent. Both conditions are known to induce a hyper-coagulable state. The objective of this study was to describe the clinical presentation and diagnostic workup of suspected PE in our setting and to determine the prevalence of HIV and TB in our sample of patients with confirmed PE.MethodsThis study was a retrospective chart review of patients with suspected PE who had CTPAs performed between October 2013 and October 2015 at a district hospital in Cape Town, South Africa. Data were collected on demographics, presenting signs and symptoms, vitals, bedside investigations, HIV and TB status. A Revised Geneva score (RGS) was calculated retrospectively and compared to the CTPA result.ResultsThe median age of patients with confirmed PE was 45 years and 68% were female. The CTPA yield for PE in our study population was 32%. The most common presenting complaint was dyspnoea (83%). Deep venous thrombosis (DVT) was present in 29%. No sign or symptom was observed to be markedly different in patients with confirmed PE vs no PE. Among patients with confirmed PE, 37% were HIV positive and 52% had current TB. RGS compared poorly with CTPA results.ConclusionsPE remains a diagnostic challenge. In our study, the retrospectively calculated CDR was not predictive of PE in a population with a high prevalence of HIV and TB. Emergency physicians should be cautious when making a clinical probability assessment of PE in this setting. However, further studies are needed to develop a predictive CDR for the local environment.

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

“…5,6,7,9 This is in keeping with other literature on HIV-infected patients where the mean ages for PE were younger than the general population, ranging from 40 to 45 years. 2,3,10,11,12 Presenting symptoms in this study were typical of that described in the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED II) trial, including shortness of breath, syncope, chest pain and haemoptysis -all of which are non-specific. 13 The CTPA prevalence of PE in an HIV-infected study population in this study was found to be 35%.…”

Diagnostic Accuracy of D-Dimer Assay in Pulmonary Embolism Using Ctpa as Gold Standard

“…12 Clinical prediction rules such as Well's and Geneva criteria to determine pretest probability for PE are validated in well-resourced countries but seem to fall short in terms of applicability in low resource settings. 7,13 Clinical prediction rules have also been shown to be unreliable in pregnancy where D-dimer had a sensitivity of 88.4% and low specificity of 8% using a standard cut off. 14 Multiple studies have been conducted to determine the diagnostic accuracy of the d-dimer assay in diagnosis of PE.…”

“…6 The diagnosis of pulmonary embolism in resource limited settings may be challenging as evidenced by the search for clinical decision rules by various set ups. 7 The D-dimer is a breakdown product of the cross linked fibrin mesh and can be used to rule out pulmonary embolism in patients with low pretest clinical probability based on specified cut off levels e.g 1000ng/ml. 6 This finding has also been found to be true in children.…”

COVID-19 Associated Pulmonary Thromboembolic Events in Anti-Coagulated Patients: Case Series from a Tertiary Facility in Ghana

“…CTPA is the gold standard for diagnosing PE [16]. However, there may be financial and logistic limitations in accessing CTPA especially in resource restrained settings, with the added challenge of exposure of technicians to COVID-19 patients [13,28]. These hindrances may lead to delayed/missed diagnosis and increased chances of mortality.…”