Antitubercular Therapy Given to Differentiate Crohn's Disease From Intestinal Tuberculosis Predisposes to Stricture Formation
Background and aim: Treatment trial with antitubercular therapy [ATT] is a common strategy in tuberculosis-endemic countries in case of a diagnostic dilemma between intestinal tuberculosis and Crohn's disease [CD]. Our aim was to determine the long-term clinical course of patients who received ATT before an eventual diagnosis of CD was made.
Methods: We performed retrospective comparison between CD patients who received ≥6 months of ATT vs those who did not receive ATT. Outcomes assessed were change in disease behaviour during follow-up, requirement of surgery and medication use.
Results: In all, 760 patients with CD were screened for the study and, after propensity matching for location and behaviour of disease, 79 patients in each group were compared. Progression from inflammatory [B1] to stricturing/fistulising [B2/B3] phenotype was increased among CD patients who received ATT [B1, B2, B3: 73.4%, 26.6%, 0% at baseline vs: 41.8%, 51.9%, 6.3% at follow-up, respectively] as compared with those who did not receive ATT [B1, B2, B3: 73.4%, 26.6%, 0% at baseline vs: 72.2%, 27.8%, 0% at follow-up, respectively] with an odds ratio of 11.05[3.17-38.56]. The usage of 5-aminosalocylates, steroids, immunosuppressants and anti-tumour necrosis factor was similar between both the groups. On survival analysis, CD patients who received ATT had a lower probability of remaining free of surgery [45%] than those who did not [76%] at 14 years of follow-up (hazard ratio [HR] = 3.22, 95% confidence interval [CI], 1.46-7.12, p = 0.004].
Conclusions: Crohn's disease patients diagnosed after a trial with antitubercular therapy had an unfavourable long-term disease course with higher rate of stricture formation and less chance of remaining free of surgery.