Hematologic and Computed Tomography Features for Discriminating COVID-19 From Non-COVID-19 Pneumonia

The clinical symptoms of COVID-19 and non-COVID-19 pulmonary infections are very similar. This study aimed to differentiate between these groups of patients by evaluating laboratory criteria and abnormalities in CT scans.

The medical records of 200 patients referred to Amir Hospital in Zabol were analyzed between February 2020 to February 2021. Some of our findings in the COVID-19 group, compared to the non-COVID-19 group, included increase in red blood cell counts (RBCs), mean corpuscular hemoglobin concentration (MCHC), mean hematocrit (HCT), erythrocyte sedimentation rate (ESR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR).

The COVID-19 group had a lower mean corpuscular volume (MCV) of 80 femtoliters (fL) and mean cell hemoglobin (MCH) below 36. The symptoms of pulmonary infection were mostly bilateral in the COVID-19 group, whereas in the non-COVID-19 group, they were predominantly unilateral. In total, 21.6% of patients had 5 to 10 lesions, while 24.7% of the non-COVID-19 group had fewer than 3 lesions. The COVID-19 group showed a distribution of both peripheral and diffuse lesions, whereas the non-COVID-19 group had a predominantly peripheral distribution. Linear opacity and ground-glass opacity (GGO) were observed in 10(6.2%) and 40(24.7%) individuals in the COVID-19 group, and in 13(8%) and 32(19.8) individuals in the non-COVID-19 group, respectively. Twenty-one (13%) COVID-19 patients and 16(9.9%) non-COVID-19 patients exhibited septal thickening. Moreover, fine reticular opacities, crazy paving patterns, and pleural effusion were observed in 6(3.7%), 19(11.7%), and 8(4.9%) of the COVID-19 patients, and in 20(12.3%), 24(14.8%), and 18(11.1%) of the non-COVID-19 patients, respectively.

Finally, this study concluded that laboratory indices such as MCV, and CT scan findings such as septal thickening are very beneficial for distinguishing between these two groups.