What is the primary treatment approach for an otherwise healthy individual presenting with infectious enteritis?

Treatment for Infectious Enteritis

The primary treatment for an otherwise healthy individual with infectious enteritis is aggressive rehydration with oral rehydration solution (ORS), while empiric antibiotics are generally NOT recommended for most cases of acute watery or bloody diarrhea unless specific high-risk features are present. 1

Core Treatment Principle: Rehydration First

Aggressive rehydration is the cornerstone of management and takes priority over all other interventions. 1

Rehydration Strategy

• Reduced osmolarity ORS is first-line therapy for mild to moderate dehydration in all age groups 1
• Intravenous isotonic fluids (lactated Ringer's or normal saline) should be administered for:
  • Severe dehydration
  • Shock or altered mental status
  • Failure of ORS therapy
  • Ileus 1
• Continue ORS until clinical dehydration is corrected, then maintain with ORS to replace ongoing stool losses 1

When Antibiotics Are NOT Indicated

For immunocompetent patients with acute watery diarrhea without recent international travel, empiric antimicrobial therapy is NOT recommended. 1

For immunocompetent patients with bloody diarrhea, empiric antibiotics while awaiting test results are NOT recommended unless specific criteria are met (see below). 1

When Antibiotics ARE Indicated

For Bloody Diarrhea - Treat Only If:

1. Infants <3 months of age with suspected bacterial etiology 1
2. Ill patients with documented fever in medical setting + abdominal pain + bloody diarrhea + bacillary dysentery (frequent scant bloody stools, fever, cramps, tenesmus) presumptively due to Shigella 1
3. Recent international travelers with temperature ≥38.5°C and/or signs of sepsis 1
4. Immunocompromised patients with severe illness and bloody diarrhea 1
5. Suspected enteric fever with sepsis features - treat empirically after obtaining blood, stool, and urine cultures 1

Empiric Antibiotic Selection

For adults meeting criteria above:

• Fluoroquinolone (ciprofloxacin) OR azithromycin depending on local susceptibility patterns and travel history 1
• Note: Increasing E. coli resistance to fluoroquinolones requires reviewing local susceptibility data 1

For children meeting criteria above:

• Third-generation cephalosporin for infants <3 months or those with neurologic involvement 1
• Azithromycin for others, based on local susceptibility and travel history 1

Critical Antibiotic Contraindication

AVOID antibiotics for STEC O157 and other STEC producing Shiga toxin 2 (or if toxin genotype unknown) - antibiotics increase risk of hemolytic uremic syndrome. 1

Supportive Care

Nutrition

• Continue breastfeeding throughout the illness 1
• Resume age-appropriate diet immediately after rehydration is complete 1

Adjunctive Medications

• Antimotility agents (loperamide), antiemetics, or antinausea drugs can be considered once adequately hydrated, but are NOT substitutes for fluid therapy 1
• Loperamide should NOT be given to children <18 years with acute diarrhea 1
• Loperamide may be given to immunocompetent adults with acute watery diarrhea 1

Special Populations

Immunocompromised Patients

• Lower threshold for empiric antibacterial treatment with severe illness and bloody diarrhea 1
• Consider broader coverage for healthcare-associated infections 1

Young Infants

• Exception to "no empiric antibiotics" rule if <3 months old and ill-appearing with suspected bacterial etiology 1

When to Modify or Stop Antibiotics

Antimicrobial treatment should be modified or discontinued when a clinically plausible organism is identified through culture results. 1

Common Pitfalls to Avoid

• Never withhold rehydration while pursuing diagnostic workup - fluid replacement is always the priority 1
• Do not treat asymptomatic contacts - they should follow infection control measures only 1
• Do not give antibiotics for STEC infections - this increases morbidity 1
• Do not use antimotility agents in children or when inflammatory/bloody diarrhea is present 1
• Avoid empiric antibiotics in most cases - the evidence shows only ~1 day symptom reduction with significant antibiotic resistance concerns 1