What is the recommended treatment for enteritis and mesenteric adenitis?

Treatment for Enteritis and Mesenteric Adenitis

The primary treatment for enteritis is oral rehydration therapy with reduced osmolarity oral rehydration solution, while antibiotics are reserved only for specific high-risk situations; mesenteric adenitis is typically managed conservatively with supportive care, reserving antibiotics only when superinfection or abscess formation is documented. 1

Initial Management Approach

Rehydration as First-Line Therapy

For enteritis, immediate oral rehydration therapy (ORT) with reduced osmolarity oral rehydration solution is the cornerstone of treatment. 1 This should be initiated without delay, even before diagnostic test results are available. 1

• Mild to moderate dehydration: Administer ORS 50-100 mL/kg over 3-4 hours in infants and children, or 2-4 L in adolescents and adults 1
• Children <10 kg: Give 60-120 mL ORS after each diarrheal stool (maximum ~500 mL/day) 1
• Children >10 kg: Give 120-240 mL ORS after each diarrheal stool (maximum ~1 L/day) 1
• Severe dehydration with shock or altered mental status: Use isotonic intravenous fluids (lactated Ringer's or normal saline) at 20 mL/kg boluses until clinical improvement 1

Supportive Care Measures

• Resume age-appropriate diet immediately after rehydration is completed 1
• Provide thromboprophylaxis with low molecular weight heparin 2
• Correct electrolyte abnormalities and anemia 2
• Avoid antimotility agents (loperamide) in children under 18 years and in patients with bloody diarrhea or fever due to risk of complications 1

When to Use Antibiotics

For Enteritis

Empiric antimicrobial therapy is NOT routinely recommended for most cases of bacterial gastroenteritis. 1 Antibiotics should only be used in specific high-risk situations:

Indications for antibiotic therapy in enteritis: 1

• Infants under 3 months of age with suspected bacterial etiology
• Immunocompromised patients with severe illness and bloody diarrhea
• Patients with fever, abdominal pain, bloody diarrhea, and bacillary dysentery
• Evidence of systemic toxicity or sepsis

Antibiotic regimens when indicated: 1

• Adults: Fluoroquinolones (ciprofloxacin) or azithromycin
• Children: Third-generation cephalosporin or azithromycin
• Pathogen-specific: Azithromycin for Campylobacter, ciprofloxacin for Shigella, ciprofloxacin/TMP-SMX/amoxicillin for Salmonella

For Mesenteric Adenitis

Antibiotics should NOT be routinely administered for mesenteric adenitis. 2, 3 They are reserved only for documented superinfection or abscess formation.

When antibiotics are indicated for mesenteric adenitis (superinfection or abscess): 2, 3

• Target Gram-negative aerobic and facultative bacilli, Gram-positive streptococci, and obligate anaerobic bacilli 2, 3
• Recommended regimens: Fluoroquinolones or third-generation cephalosporins combined with metronidazole 2, 3
• Clinical improvement should be observed within 3-5 days 2, 3

Management of Complicated Intra-Abdominal Infections

For community-acquired intra-abdominal infections of mild-to-moderate severity (including complicated enteritis with perforation):

Single-agent options: 2

• Cefoxitin, ertapenem, moxifloxacin, tigecycline, or ticarcillin-clavulanic acid

Combination regimens: 2

• Cefazolin, cefuroxime, ceftriaxone, cefotaxime, ciprofloxacin, or levofloxacin, each combined with metronidazole

Special Considerations

Abscess Management in Mesenteric Adenitis

• Small abscesses (<3 cm): May respond to antibiotic therapy alone if non-drainable, without fistula, and no steroid therapy 2, 3
• Larger abscesses: Require percutaneous drainage (ultrasound or CT-guided) plus antibiotics 2, 3
• Failed drainage: Re-evaluation with repeat imaging is necessary; repositioning of drain or surgical intervention may be required 2, 3

Neutropenic Enteritis (Typhlitis)

For immunocompromised patients with neutropenic enteritis:

• First-line treatment: Broad-spectrum antibiotics with anti-pseudomonal activity (piperacillin-tazobactam or carbapenem) 2
• Conservative management: Antibiotics plus bowel rest achieves resolution in up to 86% of patients 2
• Surgery: Reserved only for perforation or ischemia 2
• Bowel wall thickness >10 mm on imaging: Associated with 60% mortality risk versus 4.2% if <10 mm 2

Critical Pitfalls to Avoid

• Never delay rehydration while waiting for diagnostic tests 1
• Avoid antibiotics for STEC O157 infections as they increase risk of hemolytic uremic syndrome 1
• Do not use antimotility agents in children or patients with bloody diarrhea/fever 1
• Do not routinely culture or give antibiotics for uncomplicated mesenteric adenitis 2, 3
• Monitor closely for clinical deterioration in patients managed conservatively, as failure to improve within 3-5 days requires re-evaluation 2, 3

Monitoring and Follow-Up

• Continue monitoring hydration status until symptoms resolve 1
• For patients on antibiotics, reassess within 3-5 days for clinical improvement 2, 3
• If no improvement with antibiotics and drainage, repeat imaging to assess adequacy of drainage 2, 3
• Modify or discontinue antimicrobial therapy when specific pathogen is identified 1