Simple demographic, laboratory and chest radiograph variables can identify COVID-19 patients with pulmonary thromboembolism: a retrospective multicentre United Kingdom study
Published November 2023 in the British Journal of Radiology which can be read here.
To (1) identify discriminatory demographic, laboratory and initial CXR findings; (2) explore correlation between D-dimer and radiographic severity scores; and (3) assess accuracy of published D-dimer thresholds to identify pulmonary thromboembolism (PTE) in COVID-19 patients.
Our main findings:
At admission, COVID patients that were male, had a high neutrophil count, abnormal CXR and a greater CXR zonal severity score were more likely to have a PE
Only the neutrophil count at the time of peak D-dimer was a significant predictor of PE
The higher the CXR zonal severity score, the higher the D-dimer values
None of the D-dimer thresholds were reproducible in our population (ie we had a much lower sensitivy for cut off values used in similar studies across the world). I personally find these results quite interesting [see Table 3(b)] as some UK hospitals use d-dimer cut offs for CTPA requests, but our study shows that you shouldn't really use these in COVID patients as both COVID and PE can put up the D-dimer levels.
Thank you to everyone who took part in the study!