Revised Algorithmic Approach to Differentiate Between Nonspecific and Specific Etiologies of Chronic Terminal Ileitis.

INTRODUCTION: Chronic isolated terminal ileitis (TI) may be seen in Crohn's disease (CD) and intestinal tuberculosis (ITB) in addition to other etiologies that may be managed symptomatically. We developed a revised algorithm to distinguish patients with a specific etiology from a nonspecific etiology. METHODS: Patients with chronic isolated TI followed up from 2007 to 2022 were retrospectively reviewed. A specific (ITB or CD) diagnosis was made based on standardized criteria, and other relevant data were collected. Using this cohort, validation of a previously suggested algorithm was conducted. Furthermore, based on the results of a univariate analysis, a multivariate analysis with bootstrap validation was used to develop a revised algorithm. RESULTS: We included 153 patients (mean age 36.9 ± 14.6 years, males-70%, median duration-1.5 years, range: 0-20 years) with chronic isolated TI of whom 109 (71.2%) received a specific diagnosis (CD-69, ITB-40). On multivariate regression and validation statistics with a combination of clinical, laboratory, radiological, and colonoscopic findings, an optimism corrected c-statistic of 0.975 and 0.958 was obtained with and without histopathological findings, respectively. Revised algorithm, based on these, showed sensitivity, specificity, positive and negative predictive values, and overall accuracy of 98.2% (95% CI: 93.5-99.8), 75.0% (95% CI: 59.7-86.8), 90.7% (95% CI: 85.4-94.2), 94.3% (95% CI: 80.5-98.5) and 91.5%(95% CI:85.9-95.4), respectively. This was more sensitive and specific than the previous algorithm (accuracy 83.9%, sensitivity 95.5%, and specificity 54.6%). DISCUSSION: We developed a revised algorithm and a multimodality approach to stratify patients with chronic isolated TI into specific and nonspecific etiologies with an excellent diagnostic accuracy, which could potentially avoid missed diagnosis and unnecessary side effects of treatment.

Effect of oral tobacco use and smoking on outcomes of Crohn's disease in India.

BACKGROUND AND AIM: Smoking has been linked with adverse outcomes in Crohn's disease (CD); however, it is not known whether oral tobacco (OT) use affects disease outcomes in these patients. The study aimed to assess the association between smoking or OT and outcomes in CD. METHODS: Retrospective analysis was performed on prospectively maintained records of CD patients from 2004 to 2016. The parameters assessed included disease characteristics at baseline (location, behavior, age at onset, perianal disease, and extraintestinal manifestations), course pattern, and outcomes (surgery, hospitalizations, immunomodulator or biologics use, and steroid requirement). RESULTS: A total of 426 patients were included (mean age: 39.9 years; 59.9% men; median follow up: 71 months). Forty patients were ever-OT users, and 59 were ever-smokers, ever-use being defined as daily use for at least 2 years. OT use was associated with male sex and smoking. Both OT use and smoking had no effect on baseline characteristics, but upper gastrointestinal disease was less common in ever-smokers. Both OT use and smoking did not have any effect on surgery, immunomodulator, and biologic use. Similarly, no association was found between these outcomes and duration, daily, and cumulative exposure to tobacco. Current but not former tobacco use in both smoked (adjusted odds ratio = 2.59 [1.22-5.49]) and OT (adjusted odds ratio = 2.97 [1.03-8.6]) forms increased risk of hospitalizations. CONCLUSION: Oral tobacco use and smoking had no significant detrimental effect on disease phenotype or medical and surgical requirements in CD in Indian patients, affirming other non-Caucasian studies that found lack of effect of smoking. However, current tobacco use in any form was associated with hospitalization during follow up.

Evaluation of Xpert MTB/RIF assay performance in the diagnosis of abdominal tuberculosis.

BACKGROUND/AIMS: The use of genetic probes for the diagnosis of pulmonary tuberculosis (TB) has been well described. However, the role of these assays in the diagnosis of intestinal tuberculosis is unclear. We therefore assessed the diagnostic utility of the Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) assay, and estimated the prevalence of multidrug-resistant (MDR) TB in the Indian population. METHODS: Of 99 patients recruited, 37 had intestinal TB; two control groups comprised 43 with Crohn's disease (CD) and 19 with irritable bowel syndrome. Colonoscopy was performed before starting any therapy; mucosal biopsies were subjected to histopathology, acid-fast bacilli staining, Lowenstein-Jensen culture, and nucleic acid amplification testing using the Xpert MTB/RIF assay. Patients were followed up for 6 months to confirm the diagnosis and response to therapy. A composite reference standard was used for diagnosis of TB and assessment of the diagnostic utility of the Xpert MTB/RIF assay. RESULTS: Of 37 intestinal TB patients, the Xpert MTB/RIF assay was positive in three of 37 (8.1%), but none had MDR-TB. The sensitivity, specificity, positive predictive value, and negative predictive value of the Xpert MTB/RIF assay was 8.1%, 100%, 100%, and, 64.2%, respectively. CONCLUSIONS: The Xpert MTB/RIF assay has low sensitivity but high specificity for intestinal TB, and may be helpful in endemic tuberculosis areas, when clinicians are faced with difficulty differentiating TB and CD. Based on the Xpert MTB/RIF assay, the prevalence of intestinal MDR-TB is low in the Indian population.