What is the treatment for enterocolitis?

Treatment of Enterocolitis

The treatment of enterocolitis depends critically on the specific type: for neutropenic enterocolitis, initiate broad-spectrum antibiotics with IV fluids and bowel rest; for food protein-induced enterocolitis syndrome (FPIES), administer IV fluid bolus of 10-20 mL/kg as first-line treatment; for immune checkpoint inhibitor (ICI) enterocolitis, use systemic corticosteroids (0.5-2 mg/kg prednisone equivalent); and for necrotizing enterocolitis in neonates, implement bowel rest, IV fluids, and broad-spectrum antibiotics with surgical consultation for perforation. 1, 2, 3

Neutropenic Enterocolitis

Initial Medical Management

• Start broad-spectrum antibiotics immediately covering enteric gram-negative organisms, gram-positive organisms, and anaerobes 1, 2
• Recommended antibiotic regimens include monotherapy with piperacillin-tazobactam or imipenem-cilastatin, or combination therapy with cefepime or ceftazidime plus metronidazole 1, 2
• Administer granulocyte colony-stimulating factors (G-CSFs) to accelerate neutrophil recovery 1, 2
• Implement nasogastric decompression, IV fluid resuscitation, and strict bowel rest 1, 2
• Add antifungal therapy if no response to antibacterial agents, as fungemia is common in this population 2

Diagnostic Workup

• Obtain stool cultures and C. difficile testing; consider ova and parasite testing based on risk factors 1
• CT scanning is the preferred imaging modality, showing bowel wall thickening >4 mm, pericolic fluid collections, or pneumatosis intestinalis 1, 2

Surgical Indications

• Intervene surgically for persistent gastrointestinal bleeding after correcting thrombocytopenia and coagulopathy, free intraperitoneal perforation, abscess formation, or clinical deterioration despite aggressive medical management 1, 2
• Perform resection of all necrotic material, typically by right hemicolectomy; avoid primary anastomosis in severely immunocompromised patients due to high risk of anastomotic leak 2

Critical Pitfalls

• Avoid anticholinergic, antidiarrheal, and opioid agents as they aggravate ileus and mask deterioration 2, 3
• Recognize that mortality rates reach 30-82% if treatment is delayed, making early aggressive management essential 2

Food Protein-Induced Enterocolitis Syndrome (FPIES)

Acute Reaction Management

• Administer IV fluid bolus of 10-20 mL/kg as first-line treatment for symptomatic FPIES reactions 4
• Provide IV fluids for treatment of immediate reactions with hypotension and/or repetitive emesis 4
• Consider IV ranitidine in combination with diphenhydramine, though ranitidine should not be used alone due to slower onset 4
• Administer systemic steroids for severe reactions, presumably to prevent late-phase responses, though evidence is limited 4

Monitoring and Observation

• Observe patients for at least 4 hours after food challenge for FPIES reactions 4
• For positive reactions, maintain observation for approximately 6 hours after symptom resolution 4
• Repeat vital signs and physical examination every 15 minutes during active reactions, then every 30-60 minutes after resolution until discharge 4

Important Considerations

• Up to 50% of positive oral food challenges may require IV fluid treatment 4
• Home oral food challenges are not recommended given the potential for severe reactions requiring IV hydration 4
• Multiple food hypersensitivities occur in 48% of FPIES patients, approaching 80% in those with solid food or soy-induced FPIES 5

Immune Checkpoint Inhibitor (ICI) Enterocolitis

First-Line Therapy

• Administer systemic glucocorticoids at 0.5-2 mg/kg prednisone equivalent daily with a 4-6 week taper for moderate to severe cases (grade 2-4) 1
• For mild cases (grade 1-2), consider mesalamine or oral corticosteroids 1
• Withhold ICI therapy in moderate to severe cases 1

Second-Line Immunosuppression

• If no improvement within 3 days of IV corticosteroids, escalate to infliximab (5 mg/kg IV) or vedolizumab (300 mg IV) at weeks 0,2, and 6 1
• Approximately one-third of patients fail first-line glucocorticoid treatment and require second-line agents 1
• Test for C. difficile, CMV, and other infectious etiologies before starting immunosuppressive treatment 1

Biologic Selection Strategy

• Choose vedolizumab in patients with concurrent ICI hepatitis, as infliximab can induce rare hepatitis 1
• Base selection between infliximab and vedolizumab on underlying malignancy, infection risk, and concurrent immune-related adverse events 1

Critical Pitfalls

• Do not delay imaging in patients with pain, fever, or bleeding, though diarrhea alone does not warrant abdominal imaging 1
• Do not rely on CTCAE grading to predict need for second-line immunosuppression; only colonic ulceration on endoscopy is predictive 1
• Perform early endoscopy as it correlates with improved outcomes 1

Necrotizing Enterocolitis (Neonatal)

Initial Medical Management

• Implement bowel rest with nasogastric decompression 3
• Administer IV fluid resuscitation to address hemodynamic instability 3
• Start broad-spectrum IV antibiotics immediately 3

Antibiotic Regimens

• First-line options include ampicillin, gentamicin, and metronidazole; or ampicillin, cefotaxime, and metronidazole 3
• Alternative monotherapy with meropenem is acceptable 3
• Substitute vancomycin for ampicillin if MRSA or ampicillin-resistant enterococcal infection is suspected 3
• Add fluconazole or amphotericin B for suspected fungal infection 3

Surgical Indications

• Intervene urgently for evidence of bowel perforation (pneumoperitoneum) 3, 6
• Operate for clinical deterioration despite maximal medical therapy 3
• Consider peritoneal drainage as temporizing measure or definitive treatment in very low birth weight neonates 3
• Perform laparotomy with resection of necrotic bowel and creation of ostomies or primary anastomosis as appropriate 3

Monitoring

• Monitor hemodynamics with management of sepsis/septic shock 3
• Track laboratory values for thrombocytopenia, neutropenia, and metabolic acidosis 3

Outcomes

• Survival rate is approximately 95% unless NEC involves the entire bowel 3
• When entire bowel is involved, mortality increases to 40-90% 3
• Nonoperative management succeeds in approximately 70% of cases 3

Critical Pitfalls

• Avoid anticholinergic, antidiarrheal, or opioid agents as they aggravate ileus and mask deterioration 3
• Do not delay surgical consultation when perforation or clinical deterioration occurs, as failure to remove necrotic bowel is often fatal 3

Ulcerative Colitis (Severe Acute)

Initial Management

• Administer IV corticosteroids as mainstay therapy: methylprednisolone 60 mg every 24 hours or hydrocortisone 100 mg four times daily 4
• Provide IV fluid and electrolyte replacement with at least 60 mmol/day potassium supplementation, as hypokalaemia or hypomagnesaemia can promote toxic dilatation 4
• Administer subcutaneous prophylactic low-molecular-weight heparin to reduce thromboembolism risk 4

Alternative First-Line Therapy

• IV ciclosporin 4 mg/kg/day monotherapy is as effective as IV methylprednisolone for acute severe UC and is useful for patients who should avoid steroids (steroid psychosis, osteoporosis, poorly controlled diabetes) 4

Rescue Therapy Timing

• Consider therapeutic alternatives (ciclosporin, tacrolimus, or infliximab) early, on or around Day 3 of steroid therapy 4
• Do not extend steroid therapy beyond 7-10 days as it carries no additional benefit 4

Diagnostic Workup

• Perform unprepared flexible sigmoidoscopy with biopsy to confirm diagnosis and exclude cytomegalovirus infection 4
• Obtain stool cultures and C. difficile toxin assay; if C. difficile is detected, administer oral vancomycin and consider fecal microbial transplant 4

Critical Pitfalls

• Withdraw anticholinergic, anti-diarrheal, non-steroidal anti-inflammatory, and opioid drugs 4
• Avoid delaying decision-making for rescue therapy, as patients remaining on ineffective corticosteroids suffer high morbidity from delayed surgery 4