ABSTRACT
Background: Coronavirus disease 2019 (COVID-19) has killed millions of individuals and has led to the largest economic contraction since the Great Depression. The antiviral effects of vitamin D can hinder viral replication directly, and also be effective in an anti-inflammatory and immunomodulatory way. Objective: This study aimed to estimate the serum levels of free 25 hydroxycholecalciferol (25(OH)-D) in patients with COVID-19 infection in correlation to clinical manifestations and severity in multicenter tertiary-care hospitals, Egypt. Subject and Methods: This cross-sectional study included 150 confirmed patients with COVID-19 by using RT-PCR for detection of the viral RNA. The COVID-19 patients were classified into four groups of mild (n=40) moderate (n=40), severe (n=40), and critical (n=30) based on disease severity. Serum concentrations of 25(OH)-D were tested using enzyme-linked immunosorbent assay (ELISA). Results According to the current study results, all included patients (n=150) had a low level of serum levels of 25(OH)-D (11.46±4.47) in COVID-19 patients compared to normal levels. Interestingly, the levels of serum 25(OH)-D were significantly low in severe (9.5±2.71) and critical (6.26±2.58) groups compared to mild (16.37±2.62) and moderate (12.3±2.62) groups. Also, there was a significant positive correlation between serum 25(OH)-D levels and hemoglobin, platelets, albumin, and SPO2 values. On the other hand, there was a significant negative correlation between serum 25(OH)-D levels and LDH, C reactive protein, D dimer, and ferritin levels. Conclusions: Patients with COVID-19 in particular patients with severe and critical COVID-19 had a significantly low level of serum 25(OH)-D compared to mild and moderate cases, in addition, PSO2 and D dimer were independently correlated with serum 25(OH)-D, thus low serum 25(OH)-D level could be a predictor of severe and critical COVID-19. © 2021, Ain Shams University Faculty of Medicine. All rights reserved.