Nearly half of COVID-19 patients enrolled in the study conducted in the Hubei province of China presented digestive symptoms, such as diarrhea and anorexia, and cited it as their chief complaint.

In the present study, 204 patients with COVID-19 and full laboratory, imaging, and historical data were analyzed. The average age was 54.9 years (SD +15.4), including 107 men and 97 women.

The authors  found that 99 patients (48.5%) presented to the hospital with digestive symptoms as their chief complaint. Patients with digestive symptoms had a significantly longer time from onset to admission than patients without digestive symptoms (9.0 days vs. 7.3 days). Patients with digestive symptoms had a variety of manifestations, such as anorexia (83 [83.8%] cases), diarrhea (29 [29.3%] cases), vomiting (8 [0.8%] cases), and abdominal pain (4 [0.4%] cases). In 7 cases there were digestive symptoms but no respiratory symptoms.

As the severity of the disease increased, digestive symptoms became more pronounced. Patients without digestive symptoms were more likely to be cured and discharged than patients with digestive symptoms (60% vs. 34.3%). Laboratory data revealed no significant liver injury in this case series.
Clinicians should recognize that digestive symptoms, such as diarrhea, may be a presenting feature of COVID-19. The authors recommend that "the index of suspicion may need to be raised earlier in at-risk patients presenting with digestive symptoms rather than waiting for respiratory symptoms to emerge." However, further large sample studies are needed to confirm these findings.

https://journals.lww.com/ajg/pages/default.aspx