What are the updated guidelines for managing acute gastroenteritis?

Updated Guidelines for Managing Acute Gastroenteritis

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

Assessment of Dehydration Status

Evaluate hydration through specific clinical signs rather than relying on laboratory values alone 1, 2:

• Skin turgor (decreased indicates dehydration) 1, 2
• Mental status (altered consciousness suggests moderate-severe dehydration) 1, 2
• Mucous membrane moisture (dry membranes indicate dehydration) 1, 2
• Capillary refill (prolonged >2 seconds suggests poor perfusion) 1
• Vital signs (tachycardia, hypotension in severe cases) 1
• Urine output (decreased frequency and volume) 1, 2

Categorize dehydration severity 1, 2:

• Mild: 3-5% body weight loss (or <4% in some classifications) 1, 2
• Moderate: 6-9% body weight loss (or 4-6% in some classifications) 1, 2
• Severe: ≥10% body weight loss (or >6% in some classifications) 1, 2

Rehydration Strategy

For Mild to Moderate Dehydration

Use low-osmolarity ORS as first-line therapy 1, 2:

• Children: 50-100 mL/kg over 3-4 hours 2
• Adolescents and adults: 2-4 L of ORS over 3-4 hours 2
• Moderate dehydration specifically: 100 mL/kg over 2-4 hours 1

Preferred ORS formulations: Use commercially available low-osmolarity solutions (e.g., Pedialyte, CeraLyte) 2. Avoid apple juice, sports drinks (Gatorade), and commercial soft drinks as they are inappropriate for rehydration due to high sugar content and osmotic effects 1, 2.

If persistent vomiting occurs: Start with small volumes using a syringe or medicine dropper, gradually increasing as tolerated 1. Consider ondansetron in children >4 years and adolescents (0.15 mg/kg per dose) to facilitate oral rehydration 1, 2.

If oral intake is refused or inadequate: Nasogastric administration of ORS (50-100 mL/kg over 3-4 hours) may be considered 1, 2.

For Severe Dehydration

Administer intravenous rehydration immediately for patients with 1, 2:

• Severe dehydration (≥10% body weight loss)
• Shock or hemodynamic instability
• Altered mental status
• Failure of oral rehydration therapy
• Ileus

IV fluid protocol 1, 2:

• Use isotonic fluids: lactated Ringer's or normal saline 1, 2
• Initial bolus: 20 mL/kg over 30 minutes 2
• Continue IV rehydration until pulse, perfusion, and mental status normalize (typically 2-4 hours) 1, 2
• Transition to ORS to replace remaining deficit once patient improves 1

Ongoing Loss Replacement

Replace ongoing losses with ORS until diarrhea and vomiting resolve 1, 2:

• Children <10 kg: 60-120 mL ORS for each diarrheal stool/vomiting episode (up to ~500 mL/day) 2
• Children >10 kg: 120-240 mL ORS for each diarrheal stool/vomiting episode (up to ~1 L/day) 2
• Adolescents and adults: Ad libitum intake up to ~2 L/day 2
• Alternative dosing: 10 mL/kg for each watery stool and 2 mL/kg for each vomiting episode 1

Reassess hydration status after 2-4 hours; if still dehydrated, reestimate deficit and restart rehydration 1.

Nutritional Management

Resume feeding early—do not withhold food 1, 2:

• Continue breastfeeding throughout the diarrheal episode in infants 1, 2
• Resume age-appropriate diet during or immediately after rehydration 1, 2
• Avoid fasting or restrictive diets for 24 hours as this does not improve outcomes 2
• Avoid foods high in simple sugars (soft drinks, undiluted apple juice) as they exacerbate diarrhea through osmotic effects 1

Pharmacological Management

Antiemetics

Ondansetron may be given to children >4 years and adolescents with significant vomiting to facilitate oral rehydration (0.15 mg/kg per dose) 1, 2.

Antimotility Agents

Loperamide should NOT be given to children <18 years with acute diarrhea 1. Loperamide may be given to immunocompetent adults with acute watery diarrhea once adequately hydrated (4 mg initially, then 2 mg after each loose stool) 1, 2. Avoid antimotility agents in cases of inflammatory diarrhea, bloody diarrhea, fever, or suspected toxic megacolon 1, 2.

Other Agents

Do not use adsorbents, antisecretory drugs, or toxin binders as they do not demonstrate effectiveness in reducing diarrhea volume or duration 1.

Probiotics and Zinc

Probiotics may reduce symptom severity and duration in both adults and children 1. Zinc supplementation (10-20 mg daily for 10-14 days) reduces diarrhea duration in children 6 months to 5 years of age in areas with high zinc deficiency prevalence or in malnourished children 1.

Antimicrobials

Antimicrobial agents have limited usefulness since viral agents are the predominant cause 1. Consider antimicrobial therapy only in specific cases: bloody diarrhea, recent antibiotic use, exposure to certain pathogens (e.g., Shigella, Campylobacter), recent foreign travel, or immunodeficiency 1.

Infection Control Measures

Practice proper hand hygiene 1, 2:

• After using toilet or changing diapers
• Before and after food preparation
• Before eating
• After handling soiled items or animals

Use gloves and gowns when caring for people with diarrhea 1, 2. Clean and disinfect contaminated surfaces promptly 1. Separate ill persons from well persons until at least 2 days after symptom resolution 1.

Monitoring and Disposition

Monitor vital signs every 2-4 hours including capillary refill, skin turgor, mental status, and mucous membrane moisture to assess for worsening dehydration 1. Track daily weights to monitor rehydration progress 1.

Plan discharge when 1:

• Tolerating oral intake
• Producing urine
• Clinically rehydrated
• Afebrile for 24 hours (if concurrent infection confirmed)

Critical Pitfalls to Avoid

Do not delay rehydration therapy while awaiting diagnostic testing—initiate rehydration promptly 1. Do not use inappropriate fluids like apple juice or sports drinks as primary rehydration solutions for moderate to severe dehydration 1, 2. Do not administer antimotility drugs to children or in cases of bloody diarrhea 1. Do not unnecessarily restrict diet during or after rehydration 1, 2. Do not neglect infection control measures as this can lead to outbreaks 1.