Computed tomography pulmonary angiography findings in HIV positive patients referred for suspected pulmonary thrombo-embolic disease
Background: South Africa has a significant HIV burden, and imaging is commonly done as part of the workup for respiratory distress. Objectives: To document the prevalence of pulmonary thrombo-embolic disease (PTED) and other findings in HIV positive patients referred for computed tomography pulmonary angiography (CTPA) for suspected PTED in a Johannesburg based academic hospital. Method: 40 CTPA studies of documented HIV positive individuals investigated for suspected PTED during a one-year period were retrieved, anonymised and interpreted by three consultant radiologists. Inter-reader reliability was calculated using Free Marginal Kappa. Results: A total of 14 out of 40 cases (35%) were positive for PTED. In the PE positive group: 57.14% had peripheral disease and 42.86% had both peripheral and central disease. The most common findings in the PE positive cases were as follows: pulmonary infarcts (17.5%), mosaic attenuation (17.5%), linear atelectasis (7.5%). The most common incidental findings were as follows: solid pulmonary nodules (52.5%), non-wedge-shaped consolidation (45%), cardiomegaly (52.5%), enlarged intra-thoracic lymph nodes (52.5%). Thirty percent of patients had findings related directly to the presence of PTED while most cases in the study (77.5%) had pulmonary findings not related to PTED. In the PE-negative cases, 55% had emergent findings that warranted immediate or urgent medical attention. Conclusion: CTPA imaging is critical for diagnosing PE, with our study echoing imaging findings of other studies in the literature. However, further investigation into judicious application of CTPA is required, as CTPA findings in the majority of cases in our study were not related to PE.
A dissertation submitted in the fulfillment of the requirements for the degree of Master of Medicine in Diagnostic Radiology to the Faculty of Health Sciences, School of Clinical Medicine,University of the Witwatersrand, Johannesburg, 2021