Lung volumetry correlates with P/F ratio and inflammatory biomarkers in COVID-19 patients

ABSTRACT

Background: The Computed Tomography Scan (CT scan) was widely used for SARS-CoV-2 pneumonia evaluation and its correlation with clinical and laboratory findings is useful in clinical management. Aims and objectives: This study examines the clinical and functional features of COVID-19 pneumonia in relation with the extent of ground glass (GGO) and consolidation areas defined by volumetric investigations on CT scan. Method(s) Sixty-one patients attending the emergency department were enrolled. A semi-automatic segmentation software was used to extract volumetric data that has been compared with clinical and laboratory findings. Result(s) The decrease of aerated lung volume with the increase of GGO and consolidation areas were strongly related with a decrease of P/F ratio (p<0.0001, p<0.0001 and p=0.0002 respectively). An inverse correlation was observed between GGO and consolidation areas with P/F (R= -0.62, p<0.0001 and R= -0.4 and p=0.003, respectively). No significant correlation was observed between consolidation versus ground glass opacities ratio (C/GGO) and P/F. The increase of GGO and consolidation corresponded to an increase in CRP (R=-0.68, p<0.0001) and LDH (R=-0.55, p<0.0001) and a decrease in both the absolute number and the percentage of lymphocytes (respectively R= 0.48, p<0.0001 and R= 0.54, p<0.0001) with a similar increase of neutrophils (respectively R= -0.33, p=0.01 and R= -0.54, p<0.0001). These parameters had a stronger correlation with GGO than with consolidation areas. Conclusion(s) The extension and the characteristics in terms of GGO and consolidation of the lung lesions have a significant correlation with P/F reduction, CRP and LDH increase and lymphocytes decrease.