Chitotriosidase as a Potential Biomarker of Survival in Covid-19 Patients

ABSTRACT

Rationale Researchers are racing towards the goal of effective biomarker which could assess the prognosis in patients with COVID-19. Chitotriosidase (CHIT) is an integral part of immune response. This enzyme is expressed by activated macrophages. The role of CHIT in COVID-19 patients was presumed as a predictor of mortality, but this data is unclear. This study aimed to determine the potential influence of CHIT on survival in patients with COVID-19. Methods The single-center cohort prospective observational analyzed hospitalized patients with COVID-19 from November 2020 to February 2021 (Clinical Trial Registry NCT04752085). Inclusion criterion was hospitalization with COVID-19 according to the modern guidelines. Exclusion criteria were history of hospitalization with COVID-19 infection, discharge from the hospital before the end of the treatment course, transfer to another hospital. Serum chitotriosidase (CHIT) level was defined on admission. The outcomes were assessed via phone calls on 90 and 180 days. The Kaplan-Meier estimator was used in our study for assessment of survival function. Results Baseline characteristics of 357 patients with COVID-19 were following age (65.2 ± 14.1 years), gender (males 48.5%), length of illness at the time of inclusion in the study (8.1 ± 4.4 days), CT stages of lung damage 0-2 (84.3 %), 3-4 (15.7 %). 30 patients died during admission. 2 patients died in the first 30 days after discharge from hospital. 68 patients were lost to follow up within 180 days. The level of serum CHIT between survivors was significantly lower than in non-survivors (90.5 [40.2;178.0] nmol/h/mL vs 180.0 [77.2;393.2] nmol/h/mL, p=0.001). Survival of patients with baseline CHIT level greater than 171 ng/h/mL was much worse especially in the first 30 days of follow-up (Table 1). Table 1. Kaplan-Meier test showing survival in COVID-19 patients with chitotriosidase level above the cut-off of 171 nmol/ml/h. Conclusions Our study proves that CHIT level more than 171 nmol/h/mL on admission can assess a short-term prognosis. Assessment of CHIT is preferable as a potential biomarker of short-term survival. Further research needs to be conducted in larger cohorts of patients.