What is the treatment for enterocolitis?

Treatment of Enterocolitis

Context-Specific Treatment Approach

The treatment of enterocolitis depends critically on the specific type: neutropenic enterocolitis requires immediate broad-spectrum antibiotics and supportive care, necrotizing enterocolitis (NEC) in neonates demands bowel rest with antibiotics and potential surgery, immune checkpoint inhibitor (ICI) enterocolitis necessitates systemic corticosteroids, while infectious bacterial enterocolitis is often self-limiting but may require targeted antibiotics in high-risk patients. 1, 2, 3

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Neutropenic Enterocolitis

Initial Management

• Start broad-spectrum antibiotics immediately covering enteric gram-negative organisms, gram-positive organisms, and anaerobes 1
• Use either monotherapy with piperacillin-tazobactam or imipenem-cilastatin, OR combination therapy with cefepime or ceftazidime plus metronidazole 1
• Administer granulocyte colony-stimulating factors (G-CSFs) 1
• Place nasogastric tube for bowel decompression 1
• Provide intravenous fluid resuscitation 1
• Enforce strict bowel rest (NPO status) 1

Diagnostic Workup

• Obtain CT scanning as the preferred imaging modality, looking for concentric bowel wall thickening, pericolic fluid collections, or pneumatosis intestinalis 1
• Send stool cultures and C. difficile testing 1

Surgical Indications

• Persistent gastrointestinal bleeding after correcting thrombocytopenia and coagulopathy 1
• Free intraperitoneal perforation 1
• Abscess formation 1
• Clinical deterioration despite aggressive medical management 1
• Avoid primary anastomosis in severely immunocompromised patients due to high risk of anastomotic leak 1

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Necrotizing Enterocolitis (Neonates)

Immediate Interventions

• Initiate fluid resuscitation to correct hemodynamic instability, with fluid administration rate exceeding ongoing losses 2, 4
• Insert nasogastric tube for bowel decompression 2, 4
• Enforce NPO status for bowel rest 2, 4
• Start broad-spectrum intravenous antibiotics immediately 2, 4

Antibiotic Regimens (Choose One)

• First-line option: Ampicillin + gentamicin + metronidazole 2
• Alternative first-line: Ampicillin + cefotaxime + metronidazole 2
• Monotherapy option: Meropenem 2
• For suspected MRSA or ampicillin-resistant enterococcus: Substitute vancomycin for ampicillin 2
• For suspected fungal infection in extremely low birth weight infants: Add fluconazole or amphotericin B 2

Critical Monitoring

• Perform serial abdominal examinations to detect perforation early 4
• Monitor for thrombocytopenia, neutropenia, and metabolic acidosis 2
• Assess hemodynamic status continuously for sepsis/septic shock 2, 4

Surgical Indications

• Evidence of bowel perforation on imaging 2
• Clinical deterioration despite maximal medical therapy 2
• Surgical options include laparotomy with resection of necrotic bowel and creation of ostomies, or peritoneal drainage as temporizing measure in very low birth weight neonates 2
• Obtain intraoperative Gram stains and cultures to guide antimicrobial therapy 2

Critical Pitfall

• Never use anticholinergic, antidiarrheal, or opioid agents as they aggravate ileus and mask clinical deterioration 2
• Early ileostomy closure is essential to prevent chronic salt-and-water-losing states that lead to recurrent life-threatening dehydration episodes 5

Outcomes

• Survival rate is approximately 95% unless entire bowel is involved 2
• When entire bowel is involved (25% of cases), mortality increases to 40-90% 2

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Immune Checkpoint Inhibitor (ICI) Enterocolitis

Severity-Based Treatment Algorithm

Mild Cases (Grade 1-2):

• Consider mesalamine or oral corticosteroids 1
• Continue ICI therapy with close monitoring 1

Moderate to Severe Cases (Grade 3-4):

• Withhold ICI therapy immediately 1
• Administer IV corticosteroids at 0.5-2 mg/kg prednisone equivalent daily with 4-6 week taper 1
• Test for C. difficile, CMV, and other infectious etiologies BEFORE starting immunosuppressive treatment 1

Second-Line Immunosuppression (If No Improvement in 3 Days)

• Approximately one-third of patients fail first-line glucocorticoid treatment 1
• Colonic ulceration is the ONLY predictive factor for needing second-line therapy, making endoscopy critical for risk stratification 1
• Choose between infliximab (5 mg/kg IV) or vedolizumab (300 mg IV) at weeks 0,2, and 6 1
• Prefer vedolizumab in patients with concurrent ICI hepatitis, as infliximab can induce rare hepatitis 1

Critical Pitfalls

• Do not delay imaging in patients with pain, fever, or bleeding 1
• Do not rely on CTCAE grading to predict need for second-line therapy; only colonic ulceration is predictive 1
• Early endoscopy correlates with improved outcomes 1

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Severe Ulcerative Colitis (Acute Severe UC)

Initial Management

• Administer IV corticosteroids: methylprednisolone 60 mg every 24 hours OR hydrocortisone 100 mg four times daily 6
• Provide IV fluid and electrolyte replacement with at least 60 mmol/day potassium supplementation (hypokalaemia/hypomagnesaemia can promote toxic dilatation) 6
• Administer subcutaneous prophylactic low-molecular-weight heparin for thromboprophylaxis 6

Diagnostic Workup

• Perform unprepared flexible sigmoidoscopy with biopsy to confirm diagnosis and exclude CMV infection 6
• Send stool cultures and C. difficile toxin assay 6
• If C. difficile detected, administer oral vancomycin and consider fecal microbial transplant; stop immunosuppressive therapy if possible 6

Rescue Therapy (Consider Early on Day 3 of Steroid Therapy)

• Overall response to steroids is 67%, with 28% requiring colectomy 6
• Do not extend steroid therapy beyond 7-10 days as it carries no additional benefit 6
• Rescue options include infliximab, ciclosporin (2 mg/kg/day IV), or tacrolimus 6
• Ciclosporin 2 mg/kg/day monotherapy is useful for patients who should avoid steroids (steroid psychosis, osteoporosis, poorly controlled diabetes) 6

Nutritional Support

• Provide enteral nutrition if malnourished (associated with fewer complications than parenteral nutrition: 9% vs 35%) 6
• Bowel rest through IV nutrition does not alter outcomes 6

Critical Pitfall

• Withdraw anticholinergic, anti-diarrhoeal, non-steroidal anti-inflammatory, and opioid drugs 6
• Patients remaining on ineffective medical therapy suffer high morbidity from delayed surgery 6

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Infectious Bacterial Enterocolitis

Clinical Recognition

• Characterized by bloody, purulent, and mucoid stool with fever, tenesmus, and severe abdominal pain 3, 7
• Common pathogens include Campylobacter, Salmonella, Shigella, enteroinvasive/enterohemorrhagic E. coli, Yersinia, and C. difficile 3, 7

Diagnostic Approach

• Obtain stool and rectal swab culture 3, 7
• Identify specific bacterial toxins 3, 7
• Consider flexible colonoscopy with biopsy to differentiate from idiopathic ulcerative colitis and ischemic colitis 7

Treatment

• Many bacterial colitis infections are self-limiting 3
• Use antibiotics for high-risk patients and those with complicated disease 3
• Ciprofloxacin is FDA-approved for infectious diarrhea caused by enterotoxigenic E. coli, Campylobacter jejuni, Shigella species, and Salmonella typhi 8