Published online Mar 7, 2022. doi: 10.3748/wjg.v28.i9.961
Peer-review started: February 11, 2021
First decision: March 28, 2021
Revised: April 25, 2021
Accepted: January 29, 2022
Article in press: January 29, 2022
Published online: March 7, 2022
Processing time: 384 Days and 10.5 Hours
Crohn’s disease (CD) is complicated by perianal fistulas in approximately 20% of patients. Achieving permanent fistula closure remains a challenge for physicians. An association between serum anti-tumor necrosis factor-α concentrations and clinical outcomes in patients with CD has been demonstrated; however, little information is available on serum adalimumab (ADA) concentrations and remission of perianal fistulas in such patients.
To study the relationship between serum ADA concentrations and clinical remission of CD-associated perianal fistulas.
This cross-sectional study of patients with CD-associated perianal fistulas treated with ADA was performed at four French hospitals between December 2013 and March 2018. At the time of each serum ADA concentration measurement, we collected information about the patients and their fistulas. The primary study endpoint was clinical remission of fistulas defined as the absence of drainage (in accordance with Present’s criteria), with a PDAI ≤ 4, absence of a seton and assessment of the overall evaluation as favorable by the proctologist at the relevant center. We also assessed fistula healing [defined as being in clinical and radiological (magnetic resonance imaging, MRI) remission] and adverse events.
The study cohort comprised 34 patients who underwent 56 evaluations (patients had between one and four evaluations). Fifteen patients had clinical remissions (44%), four of whom had healed fistulas on MRI. Serum ADA concentrations were significantly higher at evaluations in which clinical remission was identified than at evaluations in which it was not [14 (10-16) vs 10 (2-15) μg/mL, P = 0.01]. Serum ADA concentrations were comparable at the times of evaluation of patients with and without healed fistulas [11 (7-14) vs 10 (4-16) μg/mL, P = 0.69]. The adverse event rate did not differ between different serum ADA concentrations.
We found a significant association between high serum ADA concentrations and clinical remission of CD-associated perianal fistulas.
Core Tip: Perianal fistulas (PAFs) are a complication of Crohn’s disease (CD) in approximately 20% of patients. Adalimumab (ADA) was shown to treat CD-associated PAFs; however, little information is available on serum ADA concentrations and their remission. We performed a cross-sectional study at four hospitals in France to investigate this relationship, including 34 patients with 56 evaluations. Fifteen patients had clinical remission (44%). Serum ADA concentrations were significantly higher in evaluations showing clinical remission compared to those without. Thus, ADA serum concentrations that are required for PAF remission should be higher compared with the previously described concentrations associated with luminal remission.