What is the best management for a patient with Crohn's disease, treated with infliximab (infliximab), presenting with a perianal fistula, discharge, induration, and low-grade fever for 3 weeks?

From the Guidelines

The best management for a case of Crohn's disease on infliximab presenting with perianal fistula, discharge, induration, and low-grade fever for 3 weeks would be option D, obtaining an MRI, as it provides detailed anatomical information about the fistula tract, identifies any associated abscesses, and helps determine the extent of disease 1. This patient's presentation with induration and fever suggests possible abscess formation, which requires accurate diagnosis before adjusting therapy.

Key Considerations

• While antibiotics (option B) may be needed, they should be guided by imaging findings, with metronidazole or ciprofloxacin commonly used for up to 3–4 months 1.
• Simply increasing the infliximab dose (option A) without assessing the underlying pathology could be dangerous if an abscess is present, as immunosuppression might worsen infection.
• A swab from discharge (option C) provides limited information about the fistula anatomy and wouldn't guide surgical management if needed.

Management Approach

After MRI assessment, comprehensive management would likely include:

• Drainage of any abscesses
• Appropriate antibiotics (typically ciprofloxacin and/or metronidazole)
• Optimization of medical therapy for Crohn's disease, considering higher infliximab doses may be beneficial for perianal fistulising disease, with target levels >10 μg/mL associated with better response 1.

Additional Guidance

The British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults support the use of infliximab for perianal fistulising disease, with higher levels potentially required for patients with perianal fistulae 1. A multidisciplinary approach, including surgical drainage of sepsis and adjunctive treatments like antibiotics and thiopurines, is recommended for optimal management of perianal fistulising Crohn's disease 1.

From the FDA Drug Label

In the second trial (ACCENT II [Study Crohn's II]), patients who were enrolled had to have at least 1 draining enterocutaneous (perianal, abdominal) fistula. At Week 14,65% (177/273) of patients were in fistula response Patients randomized to infliximab maintenance had a longer time to loss of fistula response compared to the placebo maintenance group Patients who achieved a fistula response and subsequently lost response were eligible to receive infliximab maintenance therapy at a dose that was 5 mg/kg higher than the dose to which they were randomized

The best management for a patient with Crohn's disease on infliximab who presents with perianal fistula and discharge, induration, and low-grade fever for 3 weeks is to continue or adjust infliximab therapy.

• The patient is already on infliximab, and the drug label suggests that patients who achieve a fistula response and subsequently lose response can be eligible to receive infliximab maintenance therapy at a dose that is 5 mg/kg higher than the dose to which they were randomized 2.
• There is no direct information in the label to support the use of antibiotics, swab from discharge, or MRI as the best management for this specific scenario.

From the Research

Best Management for Perianal Fistula and Discharge in Crohn's Disease

The best management for perianal fistula and discharge in Crohn's disease involves a combination of medical and surgical approaches.

• The use of infliximab, a chimeric monoclonal antibody targeting human tumor necrosis factor alpha (TNF), is approved for the treatment of fistulizing Crohn's disease 3.
• An exam under anesthesia (EUA) by a surgeon allows for complete inspection of the fistula as well as incision and drainage of an abscess and placement of a seton, which can improve the initial response and reduce the recurrence rate of fistulas 3.
• Combination therapy with infliximab, seton placement, and/or immunosuppressant (IS) drugs can be effective in achieving complete clinical response and stability over time 4.
• Local injections of infliximab along the fistula tract may also be an effective and safe treatment for perianal fistulas in Crohn's disease 5.
• Magnetic resonance imaging (MRI) can be used to assess the behavior of perianal fistulas before and after infliximab treatment, and to evaluate the anatomical evolution of Crohn's fistulas 6.

Diagnostic and Therapeutic Options

The following options can be considered for the management of perianal fistula and discharge in Crohn's disease:

• Increase dose of infliximab: This may not be the best option, as the initial response to infliximab is often dramatic, but the median duration of fistula closure is approximately 3 months, and repeated infusions are often required 3.
• Antibiotics: These may be used to treat any underlying infection, but are not a primary treatment for perianal fistulas in Crohn's disease.
• Swab from discharge: This may be useful for identifying any underlying infection, but is not a primary treatment for perianal fistulas in Crohn's disease.
• MRI: This can be used to assess the behavior of perianal fistulas before and after infliximab treatment, and to evaluate the anatomical evolution of Crohn's fistulas 6.

Overall Management Approach

The optimal management approach for Crohn's disease incorporates patient risk stratification, patient preference, and clinical factors in therapeutic decision-making, and may include a combination of medical and surgical approaches, including infliximab, EUA, seton placement, and/or immunosuppressant (IS) drugs 7.