Treatment Criteria for Infective Acute Gastroenteritis
The primary treatment for infective acute gastroenteritis is oral rehydration therapy (ORT) with reduced osmolarity oral rehydration solution (ORS) for mild to moderate dehydration, while severe dehydration requires intravenous fluids until vital signs normalize. 1, 2
Assessment of Hydration Status
- Evaluate hydration status through physical examination looking for:
- Mild dehydration (3-5% fluid deficit): increased thirst, slightly dry mucous membranes 1
- Moderate dehydration (6-9% fluid deficit): loss of skin turgor, tenting of skin when pinched, dry mucous membranes 1, 2
- Severe dehydration (≥10% fluid deficit): severe lethargy, altered consciousness, prolonged skin tenting (>2 seconds), cool extremities, decreased capillary refill, rapid deep breathing 1, 2
Rehydration Therapy
Oral Rehydration
- Use ORT with reduced osmolarity ORS for mild to moderate dehydration 1, 2
- Administer 50-100 mL/kg over 3-4 hours for infants and children, and 2-4 L for adolescents and adults 2
- Use commercially available low-osmolarity ORS (e.g., Pedialyte, CeraLyte) 2
- Avoid apple juice, sports drinks, and commercial soft drinks as primary rehydration solutions 2
- ORT is as effective as intravenous fluid therapy for mild to moderate dehydration 3, 4
Intravenous Rehydration
- Administer isotonic intravenous fluids (lactated Ringer's or normal saline) when there is:
- Severe dehydration
- Shock
- Altered mental status
- Failure of ORS therapy
- Ileus 1
- Continue intravenous rehydration until pulse, perfusion, and mental status normalize 1
- The remaining deficit can be replaced using ORS once the patient improves 1
Nutritional Management
- Continue breastfeeding throughout the diarrheal episode in infants 1, 2
- Resume age-appropriate diet during or immediately after rehydration 1, 2
- Avoid fasting or withholding food for prolonged periods 2
- Avoid foods high in simple sugars which can exacerbate diarrhea through osmotic effects 2
Pharmacological Management
Antimicrobial Therapy
- Empiric antimicrobial therapy is generally not recommended for immunocompetent children and adults 2
- Consider empiric antimicrobial therapy in:
- Infants <3 months with suspected bacterial etiology
- Patients with fever, abdominal pain, and bloody diarrhea
- Suspected Shigella infection 2
- Avoid antimicrobial therapy for STEC O157 and other Shiga toxin-producing E. coli as it may increase risk of hemolytic uremic syndrome 2
Symptomatic Treatments
- Antimotility drugs (e.g., loperamide):
- Antiemetics (e.g., ondansetron):
- Probiotics may be offered to reduce symptom severity and duration in immunocompetent patients 1
- Oral zinc supplementation reduces diarrhea duration in children 6 months to 5 years in zinc-deficient populations 1
Special Considerations
- Immunocompromised patients with severe illness and bloody diarrhea should receive empiric antibacterial treatment 2
- Pregnant women with Salmonella gastroenteritis should receive treatment to prevent extraintestinal spread 2
- Laboratory studies (serum electrolytes, creatinine, glucose) are usually unnecessary except in severe dehydration requiring hospitalization 4
Prevention Measures
- Practice proper hand hygiene after using toilet, changing diapers, before/after food preparation, and after handling animals 1, 2
- Use infection control measures including gloves, gowns, and hand hygiene with soap and water when caring for patients with diarrhea 1, 2
- Asymptomatic contacts of people with bloody diarrhea should follow appropriate infection prevention measures 2