What is the recommended treatment for a hemodynamically stable adult patient with infectious enterocolitis?

Treatment of Infectious Enterocolitis in Hemodynamically Stable Adults

For hemodynamically stable adults with infectious enterocolitis, treatment consists of oral or intravenous fluid resuscitation, empiric antimicrobial therapy targeting invasive bacterial pathogens (particularly Shigella, Salmonella, and Campylobacter), and supportive care—with antibiotics withheld only if Shiga toxin-producing E. coli (STEC) is suspected.

Initial Assessment and Stabilization

Fluid Resuscitation

• Begin intravenous fluid therapy immediately when infectious enterocolitis is suspected, even in the absence of overt volume depletion 1
• Volume depletion is common due to fever-induced tachypnea, poor oral intake from nausea/vomiting, and ileus from intestinal inflammation 1
• Hemodynamically stable patients without organ failure can receive urgent (rather than emergent) intervention, allowing up to 24 hours for medical stabilization with appropriate antimicrobial therapy and close monitoring 1

Diagnostic Evaluation

• Obtain stool cultures to identify invasive bacterial pathogens including Shigella, Salmonella, Campylobacter, and Shiga toxin-producing E. coli 2
• Test for C. difficile in patients with recent antibiotic exposure 3, 4
• Look for inflammatory markers in stool (leukocytes, lactoferrin, or calprotectin) to confirm inflammatory/invasive process 2
• Blood cultures are not routinely recommended for community-acquired infections unless the patient appears clinically toxic or is immunocompromised 1

Antimicrobial Therapy

Empiric Treatment

• Initiate antimicrobial therapy once infectious enterocolitis is diagnosed or strongly suspected 1
• For febrile dysenteric diarrhea, treat empirically for invasive bacterial pathogens (Shigella, Salmonella, Campylobacter) with azithromycin 1000 mg as a single oral dose 2
• Alternative empiric regimens include fluoroquinolones (ciprofloxacin 500-750 mg orally twice daily) for adults, which covers E. coli, Klebsiella, Enterobacter, Proteus, Pseudomonas, and other enteric pathogens 5
• Antimicrobials should be started in the emergency department for patients without septic shock 1

Pathogen-Specific Considerations

• Critical exception: Do NOT give antibiotics if STEC (E. coli O157:H7) is suspected, as this may precipitate hemolytic uremic syndrome 2
• STEC should be suspected when acute dysentery presents with only low-grade or absent fever 2
• Once laboratory diagnosis confirms a specific pathogen, initiate pathogen-specific antimicrobial therapy for all forms of infectious colitis except STEC 2
• For C. difficile colitis, use vancomycin or metronidazole as first-line therapy 6

Duration and Route

• Most infectious colitis cases are self-limiting, but antibiotics should be used for high-risk patients and those with complicated disease 7
• In hemodynamically stable patients with adequate gastrointestinal absorption and susceptible organisms, transition to oral antibiotics is appropriate for most Gram-negative bacteremia cases (88% of infectious disease physicians endorse this approach) 8
• Fluoroquinolones and trimethoprim-sulfamethoxazole are preferred oral agents for Gram-negative infections 8

Supportive Care

Symptom Management

• Antiemetic, antimotility, and antisecretory drugs can be used for symptom control 4
• Avoid anticholinergic, antidiarrheal, or opioid agents as they may aggravate ileus and mask clinical deterioration 9
• Oral hydration is preferred if tolerated; nasogastric or intravenous hydration for more severe illness 4

Monitoring

• Provide careful clinical monitoring during the initial 24-hour period if intervention is delayed 1
• Watch for signs of clinical deterioration that would necessitate surgical consultation 10, 3

Indications for Surgical Consultation

Absolute Indications (Require Emergency Surgery)

• Free perforation with generalized peritonitis 1, 10
• Hemodynamic instability with life-threatening hemorrhage unresponsive to resuscitation 1, 10
• Clinical deterioration despite maximal medical therapy 1, 3

Relative Indications

• Radiological signs of pneumoperitoneum and free fluid in acutely unwell patients 1
• Persistent gastrointestinal bleeding after correction of thrombocytopenia and coagulopathy 3
• Abscess formation requiring drainage 3

Common Pitfalls to Avoid

• Do not delay imaging in patients with severe pain, fever, or bleeding—CT scanning is the preferred modality to evaluate for complications 1, 3
• Do not administer antibiotics empirically if STEC is suspected based on clinical presentation (dysentery with minimal fever) 2
• Do not delay surgical consultation when peritoneal signs are present, as failure to remove necrotic bowel can be fatal 9
• Ensure adequate antimicrobial drug levels are maintained if a source control procedure becomes necessary 1