Hospital Admission for Infectious Diarrhea
No, not all patients with infectious diarrhea require hospital admission—most cases are self-limited and can be managed in outpatient settings with oral rehydration, reserving hospitalization only for those with severe dehydration, inability to tolerate oral intake, severe systemic illness, or specific high-risk features. 1, 2
Risk-Stratified Approach to Admission Decisions
Patients Who Should Be Admitted
Admit patients with any of the following criteria:
- Severe dehydration (>9% fluid loss with shock, altered mental status, or inability to drink) requiring IV fluid resuscitation 3
- Inability to tolerate oral intake or failure of oral rehydration therapy 4, 5
- Dysentery (frequent bloody stools with mucus, fever, severe abdominal cramping) suggesting invasive bacterial pathogens requiring immediate evaluation and antimicrobial therapy 6, 7
- Signs of systemic toxicity or sepsis including bacteremia risk with invasive pathogens 8, 2
- Severe or persistent vomiting preventing adequate oral rehydration 5
- Electrolyte derangements requiring IV correction 3
High-Risk Populations Requiring Lower Threshold for Admission
Consider admission for patients with mild-to-moderate symptoms if they have:
- Age >65 years 1, 2
- Immunosuppression (HIV infection, neutropenia, chemotherapy, immunomodulators) 1, 7, 2
- Significant comorbid disease 1
- Infants and young children at higher risk for rapid dehydration 7, 4
Patients Who Can Be Managed Outpatient
The majority of infectious diarrhea patients can be treated as outpatients when they have: 4, 2
- Mild-to-moderate dehydration (3-9% fluid loss) with ability to tolerate oral rehydration 3
- Acute watery diarrhea without blood, lasting 5-10 days, which is typically self-limiting 2
- No fever or systemic symptoms suggesting invasive infection 1
- Ability to maintain adequate oral intake 4
- Access to follow-up care and ability to return if symptoms worsen 1
Clinical Assessment Framework
Dehydration Severity Grading
Assess hydration status by checking for: 3
- Orthostatic hypotension
- Decreased skin turgor
- Dry mucous membranes
- Decreased urination
- Tachycardia (or paradoxical bradycardia in severe cases)
- Altered mental status
Grade as mild-to-moderate (3-9% loss) versus severe (>9% loss)—this determination drives the admission decision. 3
Inflammatory vs. Non-Inflammatory Diarrhea
Screen for inflammatory diarrhea, which increases likelihood of bacterial pathogen requiring admission: 1
- Clinical markers: Fever, tenesmus, bloody stools 1
- Laboratory confirmation: Fecal polymorphonuclear leukocytes or fecal lactoferrin testing 1
- Peripheral leukocytosis: Elevated total leukocyte count and neutrophil count suggest invasive bacterial pathogens 9
Special Considerations
For hospitalized patients developing diarrhea >3 days after admission: 1
- Do not routinely culture for standard bacterial pathogens (Campylobacter, Salmonella, Shigella) as yield is very low
- Do test for C. difficile toxin, which has 15-20% yield in this population 1
- Exception: Culture if patient admitted specifically for diarrheal illness, regardless of timing 1
Common Pitfalls to Avoid
Avoid unnecessary hospitalization for: 4, 2
- Viral gastroenteritis with adequate oral intake capability
- Mild watery diarrhea in immunocompetent adults without dehydration
- Patients who can access rapid outpatient evaluation and treatment escalation 1
Do not delay admission for: 7, 8
- Vulnerable populations (elderly, immunosuppressed, infants) even with moderate symptoms
- Any patient with signs of bacteremia or metastatic infection
- Dysentery presentation requiring immediate antimicrobial therapy 6
Pre-admission management is often suboptimal—studies show only 36% of patients receive oral rehydration solution before admission, while antidiarrheals (57%) and antiemetics (48%) are overprescribed. 5 This represents a missed opportunity to prevent hospitalization through appropriate early intervention.