Higher Anti-tumor Necrosis Factor-α Levels Correlate With Improved Radiologic Outcomes in Crohn's Perianal Fistulas

Area of Science:

• Gastroenterology
• Immunology
• Radiology

Background:

• Perianal fistulas are a common complication of Crohn's disease.
• Anti-tumor necrosis factor-α (TNF) therapies are used to manage Crohn's disease.
• The relationship between anti-TNF drug levels and radiologic healing of perianal fistulas is not well-established.

Purpose of the Study:

• To investigate the association between anti-TNF drug levels and radiologic outcomes in patients with perianal fistulising Crohn's disease.
• To determine if higher drug levels correlate with improved healing on magnetic resonance imaging (MRI).

Main Methods:

• A retrospective, cross-sectional, multicenter study included 193 patients with perianal fistulising Crohn's disease on infliximab or adalimumab.
• Drug levels were measured within 6 months of perianal MRI.
• Radiologic disease activity was assessed using the Van Assche Index, with an inflammatory subscore.

Main Results:

• Patients achieving radiologic healing had significantly higher median anti-TNF drug levels compared to those with active disease.
• Higher drug level tertiles were associated with incremental reductions in the inflammatory subscore.
• A trend towards higher drug levels was observed in patients with radiologic remission.

Conclusions:

• Elevated anti-TNF drug levels are linked to improved radiologic healing in perianal fistulising Crohn's disease.
• Optimizing anti-TNF therapy may enhance MRI-detected healing of perianal fistulas in Crohn's patients.