Calprotectin, an emerging biomarker of interest in COVID-19: Meta-analysis using Stata

COVID-19 has been shown to present with a varied clinical course, hence the need for more specific diagnostic tools that could identify severe cases and predict outcomes during COVID-19 infection. Recent evidence has shown an expanded potential role for calprotectin, both as a diagnostic tool and as a stratifying tool in COVID-19 patients in terms of severity. Therefore, this systematic review and meta-analysis aims to evaluate the levels of calprotectin in severe and nonsevere COVID-19 and also identify the implication of raised calprotectin levels. Databases searched include MEDLINE, EMBASE, the Cochrane Library, Web of Science, and MedRxiv. Stata was employed in meta-analysis to compare the serum/fecal levels of calprotectin between severe and nonsevere COVID-19 infections. A pooled analysis of data in the eight quantitative studies from 613 patients who were RT-PCR positive for COVID-19 (average age = 55 years; 52% males) showed an overall estimate as 1.34 (95% CI: 0.77, 1.91). Stata was further employed to carry out an in-depth investigation of the in-between study heterogeneity. In conclusion, calprotectin levels have been demonstrated to be significantly elevated in COVID-19 patients who develop the severe form of the disease, and it also has prognostic importance.