Table 4.

The main results of qualitative studies.

Author	Methodology	Primary Results/Conclusion
Unterman et al. (2020) [30]	Single cell analysis	Calprotectin circulating level is significantly elevated in COVID-19 patients who died. Hence, a potential role in the evaluation of prognosis in these patients.
Livanos et al. (2020) [31]	Single cell analysis	Study negates the concept of gut tropism. It reports that there is a significant decrease in severity and deaths of COVID-19 when patients present with GI symptoms such as diarrhea, nausea and vomiting