Chitotriosidase activity and dynamics of computed tomography data in COVID-19 patients

Abstract

Aim: To assess the relationship between initial plasma chitotriosidase (CHIT) activity and the dynamics of computed tomography (CT) data: lung injury volume, liver and spleen density in COVID-19 hospitalized patients.Material and Methods. The sub-analysis of the study registered in the Clinical Trial Registry with number: NCT04752085 was performed. The data of patients with available CT data of the chest on admission and at least once in dynamics during the period of hospitalization and the initial level of CTS in the blood plasma were analyzed. The density of the liver and spleen was determined in the scanned upper abdominal images, followed by the calculation of the ratio of the density of the liver to the density of the spleen.Results. A total of 121 patients were enrolled in this sub-analysis. Their baseline characteristics were as follows: median age 62 [53;70], males 48,7%. Between the day of admission and 7 [6;9] days of hospitalization, there was a significant increase in mean liver density from 52,04 [45,4; 56,7] to 57,5 [49,8; 62,7] HU and L/S ratio (liver to spleen ratio) 1,05 [0,91; 1,14] to 1,13 [0,99; 1,28], p < 0,001. The dynamics of the volume of lung tissue damage was multidirectional and, in general, did not change significantly. CHIT activity among patients whose lung injury volume increased during the hospitalization was significantly lower (65 [27; 119] nmol/ml/h) compared with patients whose lung injury volume did not change or decreased (124 [53; 232] nmol/ml/h), p = 0.006. The risk of lung injury progression was higher in patients with baseline CHIT level less than 100 nmol/h/ mL, (HR 3.1, 95% CI 1.4–6.9).Conclusion. Insufficient increase of CHIT activity can be associated with progression of lung injury, but does not affect the evolution of liver and spleen density as measured by CT.