How many days does diarrhea typically last in patients with COVID-19 (Coronavirus Disease 2019)?

Duration of Diarrhea in COVID-19

Diarrhea in COVID-19 typically lasts for a median duration of 5 days (range 2-9 days), though it can vary depending on disease severity and individual factors. 1

Epidemiology and Presentation of Diarrhea in COVID-19

• Prevalence: Diarrhea occurs in approximately 7.7% of COVID-19 patients overall, with significant geographical variation:

  • 5.8% in studies from China
  • 18.3% in studies from other countries 2

• Timing of onset:

  • Median time from illness onset to diarrhea: 3 days (IQR 0.0-5.0) 1
  • In some cases, diarrhea may precede respiratory symptoms by a few days 2
  • Only about 9% of patients present with diarrhea as the initial symptom 1

• Clinical characteristics:

  • Most common stool characteristics: watery (64%) and mushy (28%) 1
  • Defecation frequency: 37% of patients defecate more than three times daily 1
  • Often accompanied by other GI symptoms:
    • Nausea (24%)
    • Vomiting (17%)
    • Poor appetite (24%) 1

Disease Course and Prognosis

The duration and severity of diarrhea in COVID-19 patients correlate with disease outcomes:

• Patients with diarrhea only:

  • Generally milder illness
  • Longer time from symptom onset to hospital admission (14.5 days vs. 11.0 days)
  • Higher rates of viral RNA in stool (80.0% vs. 52.4%) 3

• Patients with both diarrhea and respiratory symptoms:

  • Higher levels of inflammatory activity
  • Longer hospital stays (27.5 days vs. 23.0 days for diarrhea-only patients)
  • Higher mortality risk (3.2 times higher than diarrhea-only patients) 3

Pathophysiology

The gastrointestinal manifestations of COVID-19 are related to:

• SARS-CoV-2 binding to ACE2 receptors, which are abundant in the gastrointestinal tract 4
• Disruption of intestinal microbiome
• Intestinal barrier dysfunction
• Intestinal oxidative stress
• Cytokine storm affecting the gut 5

Management Considerations

• Monitor for dehydration and electrolyte imbalances in patients with prolonged diarrhea
• Pay adequate attention to nutritional requirements during hospitalization 1
• Consider that viral RNA shedding in stool may persist longer than in respiratory specimens 4
• In outpatients with new-onset diarrhea, obtain detailed history of COVID-19 associated symptoms and potential exposure 2

Clinical Pitfalls and Caveats

• Diarrhea may be the only presenting symptom in some COVID-19 patients, potentially leading to delayed diagnosis 2
• Patients with pre-existing gastrointestinal conditions (IBD, colorectal cancer) may have increased susceptibility to COVID-19 due to higher ACE2 receptor expression in colonic mucosa 6
• Fecal-oral transmission is possible, highlighting the importance of proper sanitation and hygiene measures 4
• Diarrhea may also be a side effect of medications used to treat COVID-19, requiring monitoring of liver function tests during treatment 2