Validation of Scoring Systems for Differentiating Intestinal Tuberculosis from Crohn's Disease Utilizing Clinical, Endoscopic, and Interferon-gamma Releasing Assay in Asian Population
Differentiating CD from intestinal tuberculosis (ITB) is difficult due to the low sensitivities of currently available diagnostic tests. The Asia-Pacific guideline recommends anti-tuberculous therapy (ATT) for 8-12 weeks in patients with diagnostic uncertainty due to the risk of disseminated tuberculosis if patients with ITB are misdiagnosed with CD, and are prescribed immunosuppressive therapy. However, treatment with ATT has many side effects and may delay treatment in patients with CD, and this may cause severe relapse and developing complications. Many studies found that some clinical, endoscopy, pathology, radiology, and serology findings can help to improve diagnostic accuracy in these patients. However, no single diagnostic parameter can distinguish between CD and ITB. As a result, many models were developed that include various factors and modalities, and many of those models have been reported to have high performance. However, the number of studies performed to validate those models externally was limited. Correspondingly, this study is designed to prospectively validate models that integrate more advanced parameters (e.g., IGRA, CT enterography findings) with clinical, endoscopic, or pathological findings. However, it aims mainly to evaluate the model integrating clinical, endoscopic, and serological variables since CT enterography and pathological interpretation require experienced radiologists and pathologists but they are not available in many centers.
• Patients ages 18 years or older
• Undergoing colonoscopy and found ileal or colonic ulcers
• Have ileal and/or colonic tissue sent for mycobacterial tests, including stain for AFB, PCR, and culture
• Diagnosed with either intestinal tuberculosis or Crohn's disease a. Criteria of intestinal tuberculosis diagnosis includes any of following: i. Presence of caseating granuloma on pathological examination of specimens ii. Presence of acid-fast bacilli on pathological examination of specimens iii. PCR positive for Mycobacterium tuberculosis iv. Tissue culture growing organisms consistent with Mycobacterium tuberculosis v. Negative results in i to iv but response to empirical treatment with antituberculous therapy All are required to have clinical and endoscopic response to antituberculous therapy (ATT) treatment b. Diagnosis of Crohn's disease is based on clinical, endoscopic, pathological, and/or radiological findings which is confirmed by clinical \& endoscopic response to Crohn's disease treatment