What is the management of acute gastroenteritis?

Management of Acute Gastroenteritis

Rehydration: The Cornerstone of Treatment

Oral rehydration solution (ORS) is the first-line treatment for mild to moderate dehydration in both children and adults with acute gastroenteritis. 1, 2, 3

Assessment of Hydration Status

Evaluate dehydration severity through specific clinical signs 2, 3:

• Skin turgor (decreased in dehydration)
• Mental status (lethargy suggests moderate-severe dehydration)
• Mucous membrane moisture (dry indicates dehydration)
• Capillary refill time (>2 seconds abnormal)
• Urine output (decreased frequency/volume)

Categorize dehydration as 1, 2:

• Mild: 3-5% body weight loss
• Moderate: 6-9% body weight loss
• Severe: ≥10% body weight loss or signs of shock

Oral Rehydration Protocol

For mild to moderate dehydration 1, 2, 3:

• Infants and children: 50-100 mL/kg ORS over 3-4 hours
• Adolescents and adults (≥30 kg): 2-4 L ORS over 3-4 hours
• Use low-osmolarity ORS formulations (Pedialyte, CeraLyte, Enfalac Lytren) 1
• Do not use apple juice, sports drinks (Gatorade), or soft drinks as primary rehydration fluids 1, 2

Replace ongoing losses during maintenance 1, 2:

• Children <10 kg: 60-120 mL ORS per diarrheal stool or vomiting episode (up to ~500 mL/day)
• Children >10 kg: 120-240 mL ORS per episode (up to ~1 L/day)
• Adults: Ad libitum, up to ~2 L/day

When Oral Rehydration Fails

Nasogastric ORS administration may be considered for patients who cannot tolerate oral intake or refuse to drink adequately 1, 2

Intravenous rehydration is reserved for 1, 2, 3:

• Severe dehydration (≥10% deficit)
• Shock or altered mental status
• Failure of oral rehydration therapy
• Ileus

Use isotonic crystalloids (lactated Ringer's or normal saline) 1, 3:

• Administer 20 mL/kg boluses until pulse, perfusion, and mental status normalize 1
• Transition to ORS once patient improves to replace remaining deficit 2

Nutritional Management

Resume age-appropriate diet during or immediately after rehydration—do not fast or restrict diet. 1, 2, 3

• Continue breastfeeding throughout the illness in infants 1, 2, 3
• Offer starches (rice, potatoes, noodles), cereals, soup, yogurt, vegetables, and fresh fruits 4
• Avoid foods high in simple sugars (soft drinks, undiluted apple juice, Jell-O, presweetened cereals) as they worsen diarrhea through osmotic effects 2, 4
• Avoid high-fat foods that may delay gastric emptying 4
• Do not use diluted formulas for extended periods—inadequate nutrition 4
• The "BRAT diet" (bananas, rice, applesauce, toast) should not be used exclusively for prolonged periods due to inadequate energy and protein 4

Pharmacological Management

Antiemetics

Ondansetron may be given to children >4 years and adolescents with significant vomiting to facilitate oral rehydration 2, 3, 4

For younger children with vomiting, administer small volumes of ORS (5-10 mL) every 1-2 minutes, gradually increasing as tolerated 4

Antimotility Agents

Loperamide is contraindicated in children <18 years with acute diarrhea due to risk of serious side effects including ileus, drowsiness, and potentially fatal abdominal distention 2, 3, 4

Loperamide may be given to immunocompetent adults with acute watery diarrhea once adequately hydrated 2, 3

Adjunctive Therapies

Probiotics may reduce symptom severity and duration in both adults and children 2

Zinc supplementation reduces diarrhea duration in children 6 months to 5 years in areas with high zinc deficiency prevalence or in malnourished children 2, 3

Antimicrobials

Antimicrobials have limited usefulness since viral agents predominate in acute gastroenteritis 2, 4

Consider antimicrobial therapy only if 2, 4:

• Bloody diarrhea present
• Recent antibiotic use (consider C. difficile)
• Exposure to daycare centers where Giardia or Shigella prevalent
• Recent foreign travel
• Immunodeficiency

Do not delay rehydration while awaiting diagnostic testing or stool cultures 2, 4

Agents to Avoid

Do not use adsorbents (kaolin-pectin), antisecretory drugs, or toxin binders—they do not reduce diarrhea volume or duration and may interfere with appropriate therapy 2, 4

Infection Control Measures

Implement strict infection control to prevent transmission 2, 3:

• Hand hygiene after toilet use, diaper changes, before food preparation and eating
• Gloves and gowns when caring for patients with diarrhea
• Clean and disinfect contaminated surfaces promptly
• Separate ill persons from well persons until at least 2 days after symptom resolution

Indications for Hospitalization

Reserve hospitalization for 4:

• Severe dehydration or shock
• Failure of oral rehydration therapy
• Altered mental status
• Ileus
• Persistent vomiting preventing adequate oral intake

Critical Pitfalls to Avoid

• Do not delay rehydration while awaiting diagnostic testing 2, 4
• Do not use inappropriate fluids (apple juice, sports drinks) as primary rehydration for moderate-severe dehydration 2, 4
• Do not administer antimotility drugs to children or in bloody diarrhea 2, 3, 4
• Do not unnecessarily restrict diet during or after rehydration 2, 4
• Do not neglect infection control measures 2, 3