Endoscopic and clinical responses to anti-tubercular therapy can differentiate intestinal tuberculosis from Crohn's disease

Diagnostic value of SAT-TB in stool and urine samples for intestinal and urinary tuberculosis

BACKGROUND

The simultaneous amplification/testing for tuberculosis (SAT-TB) targets specific 16s rRNA for detecting Mycobacterium tuberculosis in real-time.

OBJECTIVE

To evaluate SAT-TB's performance in detecting intestinal and urinary TB using stool and urine samples.

METHODS

Stool (94) and urine samples (69) (From 2021 to 2022), were collected from pulmonary combined with suspected intestinal or urinary tuberculosis. Simultaneous detection of Mycobacterium tuberculosis was performed using the SAT-TB method, Xpert MTB/RIF assay, and MGIT960 culture.

RESULTS

For stool samples, the sensitivity, specificity, and area under the curve (AUC) were 53.33 %, 93.88 %, and 0.736 for SAT-TB; 60 %, 81.63 %, and 0.708 for Xpert; and 40 %, 95.92 %, and 0.680 for MGIT960. For urine samples, the sensitivity, specificity, and AUC for SAT-TB, Xpert, and MGIT960 were 27.27 %, 98.28 %, 0.628; 54.55 %, 96.35 %, 0.755; and 45.45 %, 100 %, 0.727, respectively.

CONCLUSION

ROC analysis indicated that SAT-TB had the highest diagnostic efficacy for stool samples when tested individually.

Diagnostic evaluation and management of abdominal tuberculosis

Abdominal Tuberculosis represents 11-16% of extrapulmonary tuberculosis and usually presents with vague abdominal symptoms that can mimic other diseases such as inflammatory bowel disorders, malignancy and sarcoidosis. Often the diagnosis is delayed and complications such as adhesions, obstruction, fistula or bleeding can occur. The common types are peritoneal and intestinal TB. Clinical findings should be complemented with appropriate imaging techniques such as ultrasound, CT/MRI scan, barium roentgenograms and endoscopy. Due to the paucibacillary nature, the sensitivity of AFB smear, culture, PCR assays are usually lower and interventional procedures such as endoscopy/laparoscopic biopsy should be promptly utilized wherever needed so as to initiate early treatment and avoid late complications. Standard anti-TB regimen (2RHZE/4RHE) usually achieve higher cure rates in drug sensitive TB. Close follow-up monitoring is needed to evaluate the effectiveness of proper and regular treatment. Endoscopic interventions or surgery may be required in managing complications.

Mistakes to avoid in the management of abdominal tuberculosis

INTRODUCTION

The diagnosis and management of abdominal tuberculosis, i.e Gastrointestinal Tuberculosis (GITB) and tuberculous peritonitis (TBP) is challenging. Abdominal tuberculosis, presenting usually with abdominal pain, intestinal obstruction, and constitutional symptoms, is typically a paucibacillary condition. The diagnosis hinges on a correct interpretation of clinical, radiological, histological, biochemical, and microbiological findings as also appropriately assessing response to therapy.

AREAS COVERED

The authors review potential missteps that could occur in managing GITB and TBP sourced from published literature and clinical experience. These include avoiding excess use of tests with limited accuracy, understanding limitations of ascitic adenosine deaminase (ADA) and granulomas, avoiding empirical antitubercular therapy (ATT) where possible but also understanding that microbiological tests may not always be positive, and finally not to bank solely on subjective clinical responses but to use objective markers in assessing response to therapy. In addition, diagnosis of predisposing immunosuppressed states, attention to nutrition, appropriate management of sequelae with endoscopic dilatation/surgery, and early surgery when indicated are some of the additional issues discussed.

EXPERT OPINION

In future, a more secure diagnosis banking on the use of better microbiological tools, multiparameter-based models, artificial intelligence-based approaches, and use of advances in -omics-based approaches can improve diagnosis and avoid some missteps.

Artificial intelligence-aided colonoscopic differential diagnosis between Crohn's disease and gastrointestinal tuberculosis

BACKGROUND AND AIM

Differentiating between Crohn's disease (CD) and gastrointestinal tuberculosis (GITB) is challenging. We aimed to evaluate the clinical applicability of an artificial intelligence (AI) model for this purpose.

METHODS

The AI model was developed and assessed using an internal dataset comprising 1,132 colonoscopy images of CD and 1,045 colonoscopy images of GITB at a tertiary referral center. Its stand-alone performance was further evaluated in an external dataset comprising 67 colonoscopy images of 17 CD patients and 63 colonoscopy images of 14 GITB patients from other institutions. Additionally, a crossover trial involving three expert endoscopists and three trainee endoscopists compared AI-assisted and unassisted human interpretations.

RESULTS

In the internal dataset, the sensitivity, specificity, and accuracy of the AI model in distinguishing between CD and GITB were 95.3%, 100.0%, and 97.7%, respectively, with an area under the ROC curve of 0.997. In the external dataset, the AI model exhibited a sensitivity, specificity, and accuracy of 77.8%, 85.1%, and 81.5%, respectively, with an area under the ROC curve of 0.877. In the human endoscopist trial, AI assistance increased the pooled accuracy of the six endoscopists from 86.2% to 88.8% (P = 0.010). While AI did not significantly enhance diagnostic accuracy for the experts (96.7% with AI vs 95.6% without, P = 0.360), it significantly improved accuracy for the trainees (81.0% vs 76.7%, P = 0.002).

CONCLUSIONS

This AI model shows potential in aiding the accurate differential diagnosis between CD and GITB, particularly benefiting less experienced endoscopists.

Endoscopic Monitoring of Treatment of Indeterminate Intestinal Lesions in a Prospective "Real-Life" Cohort in Eastern India Where Tuberculosis Remains Endemic: Distinguishing Intestinal Tuberculosis From Crohn's Disease

Introduction It is sometimes difficult to differentiate between intestinal tuberculosis (ITB) and Crohn's disease (CD) in India, as both conditions may mimic each other. The aim was to differentiate ITB from CD in indeterminate intestinal lesions with a therapeutic trial of anti-tubercular therapy (ATT) and follow-up to find out the clinical, endoscopic, radiological, and histological predictors for differentiation between ITB and CD. Methods A prospective observational cohort study of patients diagnosed with ITB and CD according to the Asia-Pacific Guidelines in a "real-life" clinical setting was conducted. ITB was diagnosed by Paustian criteria with Logan's modification. CD was diagnosed according to European Crohn's and Colitis Organization (ECCO) guidelines. We put the patients with a definite diagnosis of ITB and those with an indeterminate diagnosis on ATT and followed them up clinically, endoscopically, and radiologically. Patients were reassessed clinically, endoscopically, and histologically eight weeks after the start of therapy. They were again evaluated endoscopically and radiologically after completion of six months of ATT. The CD patients continued anti-inflammatory, immunomodulator, biological, and/or steroid treatments. Results We conducted this prospective study on consecutive Indian patients who had 21 definite diagnoses of ITB, 26 definite diagnoses of CD, and 42 indeterminate diagnoses. We diagnosed 49 with ITB and 28 (57%) after a therapeutic trial. Ultimately, 40 patients received a CD diagnosis, with 14 (35%) not responding to the ATT therapeutic trial. In patients with ITB, symptomatic improvement after eight weeks of ATT is correlated with endoscopic healing, especially for ulcers but not necessarily for nodularity or strictures. In 50% of these patients, minimal nodularity/pseudopolypii as well as residual scarring was seen on endoscopy even after completion of therapy. Strictures in ITB patients persisted on endoscopy in 40% despite six months of ATT. GI bleeding (64% vs. 10%; p < 0.0001), chronic diarrhea (71% vs. 35%; P = 0.02), fistula or sinuses (21% vs. 0%; p < 0.01), and multiple site involvement of the intestine (73% vs. 6%; p < 0.0001) were significantly more common in CD than in patients with ITB. Fever (82% vs. 50%; p < 0.01) and positive tuberculin tests were more common in ITB patients. PCR positivity and the presence of AFB in smear and culture could be demonstrated in only a small percentage of ITB patients. Conclusion Therapeutic trials in indeterminate intestinal lesions can distinguish ITB from CD without significant adverse effects. Strictures in patients with ITB do not resolve in all patients. GI bleeding, chronic diarrhea, fistulas or sinuses, multiple sites of involvement, and fever have the highest accuracy in differentiating ITB from CD.

New diagnostic strategies to distinguish Crohn's disease and gastrointestinal tuberculosis

PURPOSE OF REVIEW

Despite advances in our radiological, histological and microbiological armamentarium, distinguishing between Crohn's disease (CD) and intestinal tuberculosis (ITB), especially in a TB endemic country, continues to be a challenging exercise in a significant number of patients. This review aims to summarize current available evidence on novel diagnostic techniques which have a potential to fill the gap in our knowledge of differentiating between ITB and CD.

RECENT FINDINGS

Both ITB and CD are associated with altered host immune responses, and detection of these altered innate and adaptive immune cells has potential to distinguish ITB from CD. ITB and CD have different epigenetic, proteomic and metabolomic signatures, and recent research has focused on detecting these differences. In addition, the gut microbiome, which is involved in mucosal immunity and inflammatory responses, is considerably altered in both ITB and CD, and is another potential frontier, which can be tapped to discriminate between the two diseases. With technological advancements, we have newer radiological modalities including perfusion CT and dual-layer spectral detector CT enterography and evidence is emerging of their role in differentiating ITB from CD. Finally, time will tell whether the advent of artificial intelligence, with rapidly accumulating data in this field, will be the gamechanger in solving this puzzle of diagnostic dilemma between ITB and Crohn's disease.

SUMMARY

Recent advances need to be clinically validated before they can be used as novel diagnostic measures to differentiate Intestinal TB from CD.

Ten missteps in the management of inflammatory bowel disease in Asia: An expert report by the Asian Pacific Association of Gastroenterology Working Group on Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is rapidly emerging in the Asia Pacific region. However, there are many challenges in the diagnosis and management of this condition. The Asian Pacific Association of Gastroenterology (APAGE) Working Group on IBD conducted a round table meeting to identify 10 common mistakes in the management of IBD in Asia. To summarize, many physicians still over rely on a definitive histological diagnosis before starting treatment and do not fully establish disease extent such as perianal and proximal gastrointestinal involvement in Crohn's disease (CD) or extent of involvement in ulcerative colitis (UC). It is also essential to actively look for evidence of extra-intestinal manifestations, which may influence choice of therapy. In terms of conventional therapy, underuse of topical 5 aminosalicylates (5-ASAs) in UC and inappropriate dosing of corticosteroids are also important considerations. Acute severe UC remains a life-threatening condition and delay in starting rescue therapy after inadequate response to intravenous steroids is still common. Anti-tumor necrosis factors should be considered first line in all cases of complex perianal fistulizing CD. Most patients with IBD are on potent immunosuppressive therapy and should be screened for latent infections and offered vaccinations according to guidelines. Under-recognition and management of significant complications such as anemia, osteoporosis, malnutrition, and thromboembolism should also be addressed. Colonoscopy is still not properly performed for dysplasia/cancer surveillance and for evaluating post-op recurrence of CD. Another common misstep is inappropriate withdrawal of medications during pregnancy leading to increased complications for the mother and the newborn.

Multiple Tubercular Intestinal Perforations: A Case Report

Intestinal tuberculosis (TB) is a frequently encountered pathology by surgeons all over India. There exists a vast body of knowledge about this disease; however, a detailed understanding of its presentation as well as surgical management is essential for every Indian surgeon, given its rampant nature. This report discusses the case of a 28-year-old female presenting with severe left upper abdominal pain, non-bilious vomiting, and fever, who was ultimately diagnosed with small bowel TB leading to perforations. Despite a history of pulmonary TB treated a year prior, the patient exhibited significant clinical and imaging findings, including pneumoperitoneum and peritonitis. Exploratory laparotomy revealed multiple tubercular perforations in the mid-jejunum and a stricture causing proximal jejunal dilatation. Surgical intervention involved resection of the affected segment and end-to-end anastomosis. Histopathological analysis confirmed TB as the cause. This case underscores the importance of considering TB in the differential diagnosis of small bowel perforations and highlights the critical role of timely surgical intervention and comprehensive management in improving patient outcomes.

Management of Crohn's disease in Taiwan: consensus guideline of the Taiwan Society of Inflammatory Bowel Disease updated in 2023

Crohn's disease (CD) is a chronic, fluctuating inflammatory condition that primarily affects the gastrointestinal tract. Although the incidence of CD in Taiwan is lower than that in Western countries, the severity of CD presentation appears to be similar between Asia and the West. This observation indicates the urgency for devising revised guidelines tailored to the unique reimbursement system, and patient requirements in Taiwan. The core objectives of these updated guidelines include the updated treatment choices and the integration of the treat-to-target strategy into CD management, promoting the achievement of deep remission to mitigate complications and enhance the overall quality of life. Given the diversity in disease prevalence, severity, insurance policies, and access to medical treatments in Taiwan, a customized approach is imperative for formulating these guidelines. Such tailored strategies ensure that international standards are not only adapted but also optimized to local contexts. Since the inception of its initial guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease (TSIBD) has acknowledged the importance of continuous revisions for incorporating new therapeutic options and evolving disease management practices. The latest update leverages international standards and recent research findings focused on practical implementation within the Taiwanese healthcare system.

Asymptomatic intestinal tuberculosis of the terminal ileum diagnosed on colonoscopy: a case report and literature review

Objective

Colonoscopy is useful in diagnosing intestinal tuberculosis. However, the terminal ileum is generally not examined during routine colonoscopy. Therefore, even with colonoscopy, the diagnosis can be missed in patients with lesions confined to the terminal ileum. Herein, we report the case of an asymptomatic patient with intestinal tuberculosis, in whom a colonoscope insertion into the terminal ileum led to the diagnosis.

Patient

An asymptomatic 71-year-old man visited our hospital for a colonoscopy after a positive fecal occult blood test.

Results

Colonoscopy revealed diffuse edematous and erosive mucosa in the terminal ileum. Mycobacterium tuberculosis was detected by polymerase chain reaction and culture of biopsy specimens from the erosions, leading to the diagnosis of intestinal tuberculosis. The patient was treated with antitubercular agents for 6 months, and a follow-up colonoscopy revealed healing of the lesions.

Conclusion

Asymptomatic intestinal tuberculosis may occasionally be detected on colonoscopy following a positive fecal occult blood test and is sometimes confined to the terminal ileum. Therefore, clinicians should consider intestinal tuberculosis in the differential diagnosis of the causes of positive fecal occult blood test results and perform colonoscopies, including observation of the terminal ileum.

Differential diagnosis of Crohn's disease and intestinal tuberculosis based on ATR-FTIR spectroscopy combined with machine learning

BACKGROUND

Crohn's disease (CD) is often misdiagnosed as intestinal tuberculosis (ITB). However, the treatment and prognosis of these two diseases are dramatically different. Therefore, it is important to develop a method to identify CD and ITB with high accuracy, specificity, and speed.

AIM

To develop a method to identify CD and ITB with high accuracy, specificity, and speed.

METHODS

A total of 72 paraffin wax-embedded tissue sections were pathologically and clinically diagnosed as CD or ITB. Paraffin wax-embedded tissue sections were attached to a metal coating and measured using attenuated total reflectance fourier transform infrared spectroscopy at mid-infrared wavelengths combined with XGBoost for differential diagnosis.

RESULTS

The results showed that the paraffin wax-embedded specimens of CD and ITB were significantly different in their spectral signals at 1074 cm-1 and 1234 cm-1 bands, and the differential diagnosis model based on spectral characteristics combined with machine learning showed accuracy, specificity, and sensitivity of 91.84%, 92.59%, and 90.90%, respectively, for the differential diagnosis of CD and ITB.

CONCLUSION

Information on the mid-infrared region can reveal the different histological components of CD and ITB at the molecular level, and spectral analysis combined with machine learning to establish a diagnostic model is expected to become a new method for the differential diagnosis of CD and ITB.

Differentiation of Crohn's disease, ulcerative colitis, and intestinal tuberculosis by dual-layer spectral detector CT enterography

AIM

To investigate the value of radiological features and energy spectrum quantitative parameters in the differential diagnosis of Crohn's disease (CD), ulcerative colitis (UC), and intestinal tuberculosis (ITB) by dual-layer spectral detector computed tomography (CT) enterography (CTE).

MATERIALS AND METHODS

Clinical and CTE data were collected from 182 patients with CD, 29 with UC, and 51 with ITB. CT images were obtained at the enteric phases and portal phases. The quantitative energy spectrum parameters were iodine density (ID), normalised ID (NID), virtual non-contrast (VNC) value, and effective atomic number (Z-eff). The area under curve (AUC) of the receiver operating characteristic curve (ROC) was calculated.

RESULTS

The vascular comb sign (p=0.009) and enlarged lymph nodes (p=0.001) were more common in patients with CD than UC or ITB. In the differentiation of moderate-severe active CD from UC, enteric phase NID (AUC, 0.938; p<0.001) and portal phase Z-eff (AUC, 0.925; p<0.001) had the highest accuracy, which were compared separately. In the differentiation of moderate-severe active CD from ITB, enteric phase NID (AUC, 0.906; p<0.001) and portal phase Z-eff (AUC, 0.947; p<0.001) had the highest accuracy; however, the AUC value was highest when the four parameters are combined (AUC, 0.989; p<0.001; AUC, 0.986; p<0.001; AUC, 0.936; p<0.001; and AUC, 0.986; p<0.001).

CONCLUSION

The present study shows that the combined strategies of four parameters have higher sensitivity and specificity in differentiating CD, UC, and ITB, and may play a key role in guiding treatment.

Duodenal tuberculosis with gastric outlet obstruction: a case report of successful diagnosis and treatment, with review of literature

BACKGROUND

Duodenal tuberculosis (TB) is extremely rare, and its diagnosis is challenging owing to the lack of specific symptoms and radiological or endoscopic findings. When it leads to gastric outlet obstruction (GOO), diagnosing it accurately and providing appropriate treatment is crucial. However, this is often overlooked.

CASE PRESENTATION

A 35-year-old man presented with abdominal pain, fullness, vomiting, and weight loss. Upper gastrointestinal endoscopy and radiography revealed nearly pinpoint stenosis with edematous and reddish mucosa in the D1/D2 portion of the duodenum. Computed tomography (CT) showed the duodenal wall thickening, luminal narrowing, multiple enlarged abdominal lymph nodes, and portal vein stenosis. Conventional mucosal biopsy during endoscopy revealed ulcer scars. We initially suspected stenosis due to peptic ulcers; however, chest CT revealed cavitary lesions in both lung apices, suggesting tuberculosis. Due to the suspicion of duodenal TB and the need to obtain deeper tissue samples, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed. The tissue sample showed caseating granulomas with multinucleated giant cells, and acid-fast bacilli were positive by Ziehl-Neelsen staining. The patient was diagnosed with duodenal TB and subsequent GOO. Because the patient had difficulty eating, surgical intervention was prioritized over antitubercular drugs, and laparoscopic gastrojejunostomy was performed. The patient started an oral diet on the 3rd postoperative day and began antitubercular treatment immediately after discharge on the 11th day. During the 6th month of treatment, endoscopic examination revealed residual duodenal stenosis; however, the bypass route functioned well, and the patient remained asymptomatic.

CONCLUSIONS

An aggressive biopsy should be performed to diagnose duodenal TB. EUS-FNA has proven to be a useful tool in this regard. Both nutritional improvement and antitubercular treatment were achieved early and reliably by performing laparoscopic gastrojejunostomy for duodenal TB with GOO.

Visceral Fat Indices: Do They Help Differentiate Crohn's Disease and Intestinal Tuberculosis in Children?

BACKGROUND AND AIMS

Crohn's disease [CD] and intestinal tuberculosis [ITB] are often difficult to differentiate. Mesenteric fat hypertrophy is a feature of CD. We evaluated the utility of fat indices (visceral fat [VF] and subcutaneous fat [SF]) in differentiating CD and ITB in children.

METHODS

Symptomatic children diagnosed to have CD or ITB based on recommended criteria were enrolled. Clinical, anthropometric, and laboratory details were noted. Abdominal fat was measured on computed tomography in supine position at the level of L4 vertebrae. VF and SF area was measured separately by a radiologist, blinded to the diagnosis. The sum of VF and SF was taken as total fat [TF]. VF/SF and VF/TF ratios were calculated.

RESULTS

Thirty-four (age 14 years [10.8-17.0], 14 boys) children were recruited: 12 had CD [seven boys, age 13.0 years] and 22 had ITB [seven boys, age 14.5 years]. VF area was higher in CD compared to ITB (18.34 cm2 [15.62-40.01] vs 6.48 cm2 [2.65-21.96]; p = 0.012). The SF and TF area was similar in ITB and CD. The ratios of VF/SF (0.82 [0.57-1.5] vs 0.33 [0.16-0.48]; p = 0.004) and VF/TF (0.45 [0.36-0.60] vs 0.25 [0.13-0.32]; p = 0.004) were significantly higher in CD. On comparing CD and ITB in boys and girls separately, the difference was significant for boys but not for girls. A VF/SF ratio of 0.609 predicted CD with a good sensitivity [75%] and specificity [86.4%] [area under the curve 0.795, 95% confidence interval 0.636-0.955; p = 0.005].

CONCLUSION

The VF/SF ratio is a simple, non-invasive, objective parameter to differentiate CD and ITB in children, particularly boys. Larger studies are needed to validate this in girls.

Enduring Dilemmas in Gastroenterology

Making a correct diagnosis is the first, and most important, step in the therapeutic journey of a disease [...].

Assessment of CT perfusion indices of the clinicoradiological response to anti-tubercular therapy in patients with intestinal tuberculosis

AIM

To explore the possibility of using a novel technique, CT perfusion imaging, to monitor the response to anti-tubercular therapy (ATT) in patients with intestinal tuberculosis.

MATERIALS AND METHODS

A prospective observational study was performed in adults with treatment naive-intestinal tuberculosis. Clinical, endoscopic, and conventional radiological findings of patients were compared at baseline and post-ATT. CT perfusion imaging was performed with recording of six perfusion parameters (blood flow, blood volume, mean transit time, time to peak, maximum peak intensity, and permeability/blood flow extraction).

RESULTS

Twenty-two patients (13 women, 59%) with a median age of 25 years were recruited. The terminal ileum and ileocaecal junction were the most frequent sites of involvement (59%), with multiple segments of the intestine being involved in 16 patients (73%). Median duration of ATT was 6 months (range 6-10 months). Complete clinical response was observed in 22/22 (100%) patients, endoscopic response in 12/12 (100%) patients, and radiological response in 10/13 (76%) patients. There was a significant decrease in mean blood flow, blood volume, maximum peak intensity, and an increase in mean transit time and time to peak on follow-up CT perfusion imaging performed after 6 months of ATT.

CONCLUSION

Significant alterations in CT perfusion parameters were demonstrated following treatment, consistent with a decline in inflammation and vascularity. CT perfusion imaging of the bowel is a novel means to assess the radiological response to ATT in intestinal tuberculosis, although at the cost of a higher dose of radiation exposure.

Differentiating gastrointestinal tuberculosis and Crohn's disease- a comprehensive review

Gastrointestinal Tuberculosis (GITB) and Crohn's disease (CD) are both chronic granulomatous diseases with a predilection to involve primarily the terminal ileum. GITB is often considered a disease of the developing world, while CD and inflammatory bowel disease are considered a disease of the developed world. But in recent times, the epidemiology of both diseases has changed. Differentiating GITB from CD is of immense clinical importance as the management of both diseases differs. While GITB needs anti-tubercular therapy (ATT), CD needs immunosuppressive therapy. Misdiagnosis or a delay in diagnosis can lead to catastrophic consequences. Most of the clinical features, endoscopic findings, and imaging features are not pathognomonic for either of these two conditions. The definitive diagnosis of GITB can be clinched only in a fraction of cases with microbiological positivity (acid-fast bacilli, mycobacterial culture, or PCR-based tests). In most cases, the diagnosis is often based on consistent clinical, endoscopic, imaging, and histological findings. Similarly, no single finding can conclusively diagnose CD. Multiparametric-based predictive models incorporating clinical, endoscopy findings, histology, radiology, and serology have been used to differentiate GITB from CD with varied results. However, it is limited by the lack of validation studies for most such models. Many patients, especially in TB endemic regions, are initiated on a trial of ATT to see for an objective response to therapy. Early mucosal response assessed at two months is an objective marker of response to ATT. Prolonged ATT in CD is recognized to have a fibrotic effect. Therefore, early discrimination may be vital in preventing the delay in the diagnosis of CD and avoiding a complicated course.

Computed tomography enterography-based multiregional radiomics model for differential diagnosis of Crohn's disease from intestinal tuberculosis

PURPOSE

To build computed tomography enterography (CTE)-based multiregional radiomics model for distinguishing Crohn's disease (CD) from intestinal tuberculosis (ITB).

MATERIALS AND METHODS

A total of 105 patients with CD and ITB who underwent CTE were retrospectively enrolled. Volume of interest segmentation were performed on CTE and radiomic features were obtained separately from the intestinal wall of lesion, the largest lymph node (LN), and region surrounding the lesion in the ileocecal region. The most valuable radiomic features was selected by the selection operator and least absolute shrinkage. We established nomogram combining clinical factors, endoscopy results, CTE features, and radiomic score through multivariate logistic regression analysis. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the prediction performance. DeLong test was applied to compare the performance of the models.

RESULTS

The clinical-radiomic combined model comprised of four variables including one radiomic signature from intestinal wall, one radiomic signature from LN, involved bowel segments on CTE, and longitudinal ulcer on endoscopy. The combined model showed good diagnostic performance with an area under the ROC curve (AUC) of 0.975 (95% CI 0.953-0.998) in the training cohort and 0.958 (95% CI 0.925-0.991) in the validation cohort. The combined model showed higher AUC than that of the clinical model in cross-validation set (0.958 vs. 0.878, P = 0.004). The DCA showed the highest benefit for the combined model.

CONCLUSION

Clinical-radiomic combined model constructed by combining CTE-based radiomics from the intestinal wall of lesion and LN, endoscopy results, and CTE features can accurately distinguish CD from ITB.

Clinical characteristics and diagnosis of intestinal tuberculosis in clinical practice at Thailand's largest national tertiary referral center: An 11-year retrospective review

BACKGROUND

Diagnosing intestinal tuberculosis (ITB) is challenging due to the low diagnostic sensitivity of current methods. This study aimed to assess the clinical characteristics and diagnosis of ITB at our tertiary referral center, and to explore improved methods of ITB diagnosis.

METHODS

This retrospective study included 177 patients diagnosed with ITB at Siriraj Hospital (Bangkok, Thailand) during 2009-2020.

RESULTS

The mean age was 49 years, 55.4% were male, and 42.9% were immunocompromised. Most diagnoses (108/177) were made via colonoscopy; 12 patients required more than one colonoscopy. Among those, the sensitivity of tissue acid-fast bacilli (AFB), presence of caseous necrosis, polymerase chain reaction (PCR), and culture was 40.7%, 13.9%, 25.7%, and 53.4%, respectively. Among patients with negative tissue histopathology, 4 (3.7%) and 13 (12.0%) were ITB positive on tissue PCR and culture, respectively. The overall sensitivity when all diagnostic methods were used was 63%. Seventy-six patients had stool tests for mycobacteria. The overall sensitivity of stool tests was 75.0%. However, when analyzing the 31 patients who underwent both endoscopy and stool testing, the sensitivity of stool testing when using tissue biopsy as a reference was 45.8%. Combining stool testing and tissue biopsy did not significantly increase the sensitivity compared to tissue biopsy alone (83.9% vs. 77.4%, respectively).

CONCLUSION

Despite the availability of PCR and culture for TB, the overall diagnostic sensitivity was found to be low. The sensitivity increased when the tests were used in combination. Repeated colonoscopy may be beneficial. Adding stool mycobacteria tests did not significantly increase the diagnostic yield if endoscopy was performed, but it could be beneficial if endoscopy is unfeasible.

Comparative evaluation of interleukin-10, transforming growth factor-β, and interleukin-17 in gastrointestinal tuberculosis and crohn's disease

Background

Gastrointestinal tuberculosis (GITB) and Crohn's disease (CD) are close mimickers and difficult to discriminate. Recent work has focused on the immunological differences between GITB and CD based on cytokines related to T-regulatory cells and Th17 cells. In the present cross-sectional study, suspected cases of GITB or CD underwent extensive clinical, radiological, endoscopic, histological, and microbiological assessment. The diagnosis was based on standard criteria and response to antitubercular therapy endoscopically.

Methods

Interleukin (IL)-10, transforming growth factor-β (TGF-β), and IL-17 were measured and compared between GITB and CD along with other parameters. Fisher's exact test and Mann-Whitney U test were used as per the data type.

Results

Of the 27 patients, 11 had CD, 9 had GITB, and 7 had other conditions. Chronic diarrhea, involvement of left and long segments of the colon, and aphthous ulcers were significantly more frequent in CD; however, transverse ulcers were in GITB. IL-10 was reduced in both GITB (median-interquartile range [IQR] 9.54 [3.65-24.04]) and CD (median-IQR 13.28 [6.91-22.50]) compared to control (median-IQR 26.72 [10.34-35.43]). TGF-β showed little variation, but IL-17 was below the detection limit in most cases. None of these cytokines were significantly different between CD and GITB. The sensitivity and specificity of multiplex Mycobacterium tuberculosis-polymerase chain reaction were 44.44% and 100%, respectively.

Conclusion

Serum cytokine profiling (IL-10, IL-17, and TGF-β) could not significantly differentiate GITB and CD. Moreover, extensive molecular, transcriptomic, chemokines, and cytokine analyses may shed light on these aspects.

Applying logistic LASSO regression for the diagnosis of atypical Crohn's disease

In countries with a high incidence of tuberculosis, the typical clinical features of Crohn's disease (CD) may be covered up after tuberculosis infection, and the identification of atypical Crohn's disease and intestinal tuberculosis (ITB) is still a dilemma for clinicians. Least absolute shrinkage and selection operator (LASSO) regression has been applied to select variables in disease diagnosis. However, its value in discriminating ITB and atypical Crohn's disease remains unknown. A total of 400 patients were enrolled from January 2014 to January 2019 in second Xiangya hospital Central South University.Among them, 57 indicators including clinical manifestations, laboratory results, endoscopic findings, computed tomography enterography features were collected for further analysis. R software version 3.6.1 (glmnet package) was used to perform the LASSO logistic regression analysis. SPSS 20.0 was used to perform Pearson chi-square test and binary logistic regression analysis. In the variable selection step, LASSO regression and Pearson chi-square test were applied to select the most valuable variables as candidates for further logistic regression analysis. Secondly, variables identified from step 1 were applied to construct binary logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was performed on these models to assess the ability and the optimal cutoff value for diagnosis. The area under the ROC curve (AUC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy rate, together with their 95% confidence and intervals (CIs) were calculated. MedCalc software (Version 16.8) was applied to analyze the ROC curves of models. 332 patients were eventually enrolled to build a binary logistic regression model to discriminate CD (including comprehensive CD and tuberculosis infected CD) and ITB. However, we did not get a satisfactory diagnostic value via applying the binary logistic regression model of comprehensive CD and ITB to predict tuberculosis infected CD and ITB (accuracy rate:79.2%VS 65.1%). Therefore, we further established a binary logistic regression model to discriminate atypical CD from ITB, based on Pearsonchi-square test (model1) and LASSO regression (model 2). Model 1 showed 89.9% specificity, 65.9% sensitivity, 88.5% PPV, 68.9% NPV, 76.9% diagnostic accuracy, and an AUC value of 0.811, and model 2 showed 80.6% specificity, 84.4% sensitivity, 82.3% PPV, 82.9% NPV, 82.6% diagnostic accuracy, and an AUC value of 0.887. The comparison of AUCs between model1 and model2 was statistically different (P < 0.05). Tuberculosis infection increases the difficulty of discriminating CD from ITB. LASSO regression showed a more efficient ability than Pearson chi-square test based logistic regression on differential diagnosing atypical CD and ITB.

Addition of computed tomography chest increases the diagnosis rate in patients with suspected intestinal tuberculosis

BACKGROUND/AIMS

Intestinal tuberculosis (ITB) is difficult to diagnose due to poor sensitivity of definitive diagnostic tests. ITB may be associated with concomitant pulmonary tuberculosis (PTB) which may remain undetected on chest X-ray. We assessed the role of contrast enhanced computed tomography (CECT) chest in detecting the prevalence of active PTB, and increasing the diagnostic yield in patients with suspected ITB.

METHODS

Consecutive treatment naïve patients with suspected ITB (n=200) who underwent CECT chest (n=88) and had follow-up duration>1 year were recruited in this retrospective study (February 2016 to October 2018). ITB was diagnosed in the presence of caseating granuloma, positive acid fast stain or culture for Mycobacterium tuberculosis on biopsy, presence of necrotic lymph nodes (LNs) on CT enterography or positive response to anti-tubercular therapy. Evidence of active tuberculosis on CECT-chest was defined as presence of centrilobular nodules with or without consolidation/miliary nodules/thick-walled cavity/enlarged necrotic mediastinal LNs.

RESULTS

Sixty-five of eighty-eight patients (mean age, 33.8±12.8 years; 47.7% of females) were finally diagnosed as ITB (4-caseating granuloma on biopsy, 12-necrotic LNs on CT enterography, 1-both, and 48-response to anti-tubercular therapy) and 23 were diagnosed as Crohn's disease. Findings of active TB on CECT chest with or without necrotic abdominal LNs were demonstrated in 5 and 20 patients, respectively. No patient with Crohn's disease had necrotic abdominal LNs or active PTB. Addition of CECT chest in the diagnostic algorithm improved the sensitivity of ITB diagnosis from 26.2% to 56.9%.

CONCLUSIONS

Addition of CECT chest significantly improves the sensitivity for definite diagnosis in a patient with suspected ITB.

ECCO Topical Review on Clinicopathological Spectrum and Differential Diagnosis of Inflammatory Bowel Disease

INTRODUCTION

Many diseases can imitate inflammatory bowel disease [IBD] clinically and pathologically. This review outlines the differential diagnosis of IBD and discusses morphological pointers and ancillary techniques that assist with the distinction between IBD and its mimics.

METHODS

European Crohn's and Colitis Organisation [ECCO] Topical Reviews are the result of an expert consensus. For this review, ECCO announced an open call to its members and formed three working groups [WGs] to study clinical aspects, pathological considerations, and the value of ancillary techniques. All WGs performed a systematic literature search.

RESULTS

Each WG produced a draft text and drew up provisional Current Practice Position [CPP] statements that highlighted the most important conclusions. Discussions and a preliminary voting round took place, with subsequent revision of CPP statements and text and a further meeting to agree on final statements.

CONCLUSIONS

Clinicians and pathologists encounter a wide variety of mimics of IBD, including infection, drug-induced disease, vascular disorders, diverticular disease, diversion proctocolitis, radiation damage, and immune disorders. Reliable distinction requires a multidisciplinary approach.

Differentiation of intestinal tuberculosis and Crohn's disease through an explainable machine learning method

Differentiation between Crohn’s disease and intestinal tuberculosis is difficult but crucial for medical decisions. This study aims to develop an effective framework to distinguish these two diseases through an explainable machine learning (ML) model. After feature selection, a total of nine variables are extracted, including intestinal surgery, abdominal, bloody stool, PPD, knot, ESAT-6, CFP-10, intestinal dilatation and comb sign. Besides, we compared the predictive performance of the ML methods with traditional statistical methods. This work also provides insights into the ML model’s outcome through the SHAP method for the first time. A cohort consisting of 200 patients’ data (CD = 160, ITB = 40) is used in training and validating models. Results illustrate that the XGBoost algorithm outperforms other classifiers in terms of area under the receiver operating characteristic curve (AUC), sensitivity, specificity, precision and Matthews correlation coefficient (MCC), yielding values of 0.891, 0.813, 0.969, 0.867 and 0.801 respectively. More importantly, the prediction outcomes of XGBoost can be effectively explained through the SHAP method. The proposed framework proves that the effectiveness of distinguishing CD from ITB through interpretable machine learning, which can obtain a global explanation but also an explanation for individual patients.

A Novel Clinical Radiomics Nomogram to Identify Crohn's Disease from Intestinal Tuberculosis

Purpose

To establish a clinical radiomics nomogram to differentiate Crohn’s disease (CD) from intestinal tuberculosis (ITB).

Patients and Methods

Ninety-three patients with CD and 67 patients with ITB were recruited (111 in training cohort and 49 in test cohort). The region of interest (ROI) for the lesions in the ileocecal region was delineated on computed tomography enterography and radiomics features extracted. Radiomics features were filtered by the gradient boosting decision tree (GBDT), and a radiomics score was calculated by using the radiomics signature-based formula. We constructed a clinical radiomics model and nomogram combining clinical factors and radiomics score through multivariate logistic regression analysis, and the internal validation was undertaken by ten-fold cross validation. Analyses of receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the prediction performance. DeLong test was applied to evaluate the performance of the clinical, radiomics and combined model.

Results

The clinical radiomics nomogram, which was based on the 9 radiomics signature and two clinical factors, indicated that the clinical radiomics model had an area under the ROC curve (AUC) value of 0.96 (95% confidence interval [CI]: 0.93–0.99) in the training cohort and 0.93 (95% CI: 0.86–1.00) in validation cohort. The clinical radiomics model was superior to the clinical model and radiomics model, and the difference was significant (P = 0.006, 0.004) in the training cohort. DCA confirmed the clinical utility of clinical radiomics nomogram.

Conclusion

CTE-based radiomics model has a good performance in distinguishing CD from ITB. A nomogram constructed by combining radiomics and clinical factors can help clinicians accurately diagnose and select appropriate treatment strategies between CD and ITB.

A combination of circulating microRNA-375-3p and chemokines CCL11, CXCL12, and G-CSF differentiate Crohn's disease and intestinal tuberculosis

Differentiation of Crohn’s disease (CD) from intestinal tuberculosis (ITB) is a big challenge to gastroenterologists because of their indistinguishable features and insensitive diagnostic tools. A non-invasive biomarker is urgently required to distinguish ITB/CD patients particularly in India, a TB endemic region, where CD frequency is increasing rapidly due to urbanization. Among the three differentially expressed miRNAs obtained from small RNA transcriptomic profiling of ileocaecal/terminal ileal tissue of ITB/CD patients (n = 3), only two down-regulated miRNAs, miR-31-5p, and miR-215-5p showed comparable data in qRT-PCR. Out of which, only miR-215-5p was detectable in the patient’s plasma, but there was no significant difference in expression between ITB/CD. On the other hand, miR-375-3p, the pulmonary TB specific marker was found in higher amount in the plasma of ITB patients than CD while reverse expression was observed in the ileocaecal/terminal ileal tissues of the same patients. Next, using Bioplex pro-human cytokine 48-plex screening panel, only three chemokines, Eotaxin-1/CCL11, SDF-1α/CXCL12, and G-CSF have noted significantly different levels in the serum of ITB/CD patients. ROC analysis has revealed that compared to a single molecule, a combination of miR-375-3p + Eotaxin-1/CCL11 + SDF-1α /CXCL12 + G-CSF showed a better AUC of 0.83, 95% CI (0.69–0.96) with 100% specificity and positive predictive value while sensitivity, negative predictive value, and accuracy were 56%, 69%, and 78% respectively in distinguishing ITB from CD. This study suggests that a combination of plasma markers shows better potential in differentiating ITB from CD than a single marker and this panel of markers may be used for clinical management of ITB/CD patients.

An outcome-based composite approach for the diagnosis of intestinal tuberculosis: a pilot study from a tertiary care centre in South India

BACKGROUND

The diagnosis of intestinal TB (ITB) is challenging because of its overlapping features with Crohn's disease. This outcome-based study evaluated the combination of colonoscopy, histopathology, Xpert MTB/RIF and TB culture for best sensitivity and specificity.

METHOD

This was a four-year retrospective, observational study of 426 clinically suspected patients who underwent colonoscopy with biopsies for histopathology, Xpert MTB/RIF and TB culture. ITB was diagnosed using the composite reference standard (CRS), which comprised either histological features or culture or Xpert MTB/RIF positivity, and positive response to anti-tuberculous treatment on follow up.

RESULTS

35 (8.2%) patients were diagnosed with ITB. Histopathology had the highest sensitivity (91.4%) and negative predictive value (99.2%), MTB/RIF had the highest specificity (100%) and positive predictive value (100%). A combinatorial approach with Xpert MTB/RIF and histopathology had optimal diagnostic value (97%), approaching 100% sensitivity with culture. 40% of cases were diagnosed within 12 hours with Xpert MTB/RIF and 97% cases within three days.

CONCLUSION

This combinatorial diagnostic model provides rapid and reliable diagnosis of ITB which may be useful in endemic areas.

Gastrointestinal tuberculosis: A systematic review of epidemiology, presentation, diagnosis and treatment

Tuberculosis (TB) once considered a disease of the developing world is infrequent in the developing world too. Its worldwide prevalence with a huge impact on the healthcare system both in economic and health terms has prompted the World Health Organization to make it a top priority infectious disease. Tuberculous infection of the pulmonary system is the most common form of this disease, however, extrapulmonary TB is being increasingly recognized and more often seen in immunocompromised situations. Gastrointestinal TB is a leading extrapulmonary TB manifestation that can defy diagnosis. Overlap of symptoms with other gastrointestinal diseases and limited accuracy of diagnostic tests demands more awareness of this disease. Untreated gastrointestinal TB can cause significant morbidity leading to prolonged hospitalization and surgery. Prompt diagnosis with early initiation of therapy can avoid this. This timely review discusses the epidemiology, risk factors, pathogenesis, clinical presentation, current diagnostic tools and therapy.

Application value of tissue tuberculosis antigen combined with Xpert MTB/RIF detection in differential diagnoses of intestinal tuberculosis and Crohn's disease

Background

The purpose of this study was to examine the value of Xpert MTB/RIF assay and detection of additional Mycobacterium tuberculosis complex (MTBC) species antigens from intestinal tissue samples in differentiating intestinal tuberculosis (ITB) from Crohn’s disease (CD).

Methods

Several clinical specimens of intestinal tissue obtained by either endoscopic biopsy or surgical excision were used for mycobacteriologic solid cultures,Xpert MTB/RIF assays, immunohistochemistry, and histological examinations. Four antigens (38KDa, ESAT-6, MPT64, and Ag85 complex) of MTBC in the intestinal tissue were detected by immunohistochemical analysis.

Results

The study included 42 patients with ITB and 46 with CD. Perianal lesions and longitudinal ulcers were more common in patients with CD, while caseating granuloma and annular ulcers were more common in patients with ITB. The positive rate of MTBC detected by Xpert MTB/RIF in intestinal tissues of patients with ITB was 33.33%, which was significantly higher than that in patients with CD and that detected using acid-fast staining smears. It was also higher than that detected by tissue MTBC culture, but the difference was not statistically significant. The positive MPT64 expression rate in patients with ITB was 40.48%, which was significantly higher than that observed in patients with CD. The sensitivity of parallelly combined detection of tuberculosis protein MPT64 and Xpert MTB/RIF in diagnosing ITB was 50.0%.

Conclusions

The detection of Xpert MTB/RIF in intestinal tissue is a rapid and useful method for establishing an early diagnosis of ITB. The detection of MTBC using Xpert MTB/RIF and MPT64 antigen in intestinal tissues has a definitive value in the differential diagnosis ofITB and CD. The combination of these two methods can improve the detection sensitivity.

Inflammatory bowel disease: An Indian perspective

Inflammatory bowel disease (IBD) in recent times is causing a significant healthcare burden as both ulcerative colitis and Crohn's disease (CD) require lifelong therapy and constant monitoring. The current review highlights the concerns in a country like India with special reference to the changing trends of IBD, risk attribution and the financial issues. Indian immigrants behave like residential Indians, whereas their children show IBD prevalence similar to the West, highlighting the role of environmental triggers. However, the environmental and genetic factors in Indians with IBD are not well understood. Men appear to be more frequently affected than women in India. The disease severity is milder in the patients, both males and females, but the risk for colorectal cancer (CRC) is similar to the West. The incidence of paediatric IBD is on the rise. The major burden of IBD in the Indian subcontinent at present is in children, adolescents and teens. Cost towards the management of complications, non-adherence to treatment, differentiating tuberculosis from CD and finally screening for CRC in patients with IBD are the points to ponder in the Indian scenario.

Serial measurements of faecal calprotectin may discriminate intestinal tuberculosis and Crohn's disease in patients started on antitubercular therapy

BACKGROUND

Response to antitubercular therapy (ATT) is often used to differentiate intestinal tuberculosis (ITB) from Crohn's disease. Role of non-invasive biomarkers to predict mucosal response to ATT is unclear.

MATERIALS AND METHODS

A prospective study to compare faecal calprotectin and serum C-reactive protein (CRP) levels at diagnosis, 2 and 6 months of ATT in patients with suspected ITB started on ATT was done. The patients were eventually divided into two groups: ITB or alternative diagnosis (OTH). Decline of calprotectin and CRP levels was used to compute area under the receiver operating characteristic (AUROC) to predict mucosal healing at 2 months.

RESULTS

Thirty-seven patients (mean age: 34.95 ± 16.35 years, 23 males) were included and 28 (75.67%) were diagnosed as ITB while nine (24.32%) had alternative diagnosis (OTH). The median faecal calprotectin values of ITB and OTH groups at baseline, 2 months and 6 months were 216 and 282 µg/g (P = 0.466), 43 and 216 µg/g (P = 0.003), and 26 and 213 µg/g (P < 0.001), respectively. The median CRP values at baseline, 2 months and 6 months were 18 and 30 mg/L (P = 0.767), 4.7 and 15 mg/L (P = 0.025), and 3 and 10.85 mg/L (P = 0.068), respectively. The AUROC of percent decline in faecal calprotectin and serum CRP at 2 months for mucosal healing were 0.8287 [95% confidence inteval (CI) 0.6472-1] and 0.6018 (95% CI 0.4079-0.7957), respectively.

CONCLUSION

Faecal calprotectin can help in assessing response to therapy in suspected ITB patients started on empirical ATT.

Asian Organization for Crohn's and Colitis and Asia Pacific Association of Gastroenterology practice recommendations for medical management and monitoring of inflammatory bowel disease in Asia

Inflammatory bowel disease (IBD) has increased in incidence and prevalence in Asian countries since the end of the 20th century. Moreover, differences in the cause, phenotypes, and natural history of IBD between the East and West have been recognized. Therefore, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have established recommendations on medical management of IBD in Asia. Initially, the committee members drafted 40 recommendations, which were then assessed according to Grading of Recommendations Assessment, Development and Evaluation. Eight statements were rejected as this indicated that consensus had not been reached. The recommendations encompass pretreatment evaluation; medical management of active IBD; medical management of IBD in remission; management of IBD during the periconception period and pregnancy; surveillance strategies for colitis-associated cancer; monitoring side effects of thiopurines and methotrexate; and infections in IBD.

Intestinal Tuberculosis: A Diagnostic Challenge

Diagnosing intestinal tuberculosis (TB) with uncommon clinical manifestations is often challenging. Here, we report a case of an alcoholic patient who presented with vague symptoms and was later diagnosed with intestinal TB. This patient experienced multiorgan failure causing hemodynamic instability requiring ionotropic support; acute hypoxic respiratory failure managed with non-invasive positive pressure ventilation, hepatic failure, transudative peritoneal effusion, and transudative pleural effusion. These conditions clouded our judgment to pursue colonoscopy for a definite diagnosis and delayed the anti-tuberculosis treatment. When intestinal tuberculosis TB is suspected, the differential diagnosis must be established with other gastrointestinal involving diseases, including mycobacterium avium complex (MAC) and Crohn's disease (CD). MAC can show overlapping features with intestinal TB or coexist with it; Acid-fast stain and tissue culture are the key tests to differentiate these two. In the presence of diagnostic uncertainty between intestinal TB and CD, a therapeutic trial with anti-tuberculous therapy may be warranted.

Systematic reporting of computed tomography enterography/enteroclysis as an aid to reduce diagnostic dilemma when differentiating between intestinal tuberculosis and Crohn's disease: A prospective study at a tertiary care hospital

Background and Aim

Crohn's disease (CD) and intestinal tuberculosis (ITB) have similar symptomatology and overlapping features on imaging, endoscopy, and histopathology. It is important to differentiate ITB from CD to initiate correct medical management. This prospective study aimed to characterize imaging features on computed tomography enteroclysis/enterography (CTE) that help in differentiating ITB from CD.

Methods

A total of 300 consecutive patients who underwent CTE with the suspicion of small bowel diseases were evaluated. CTE findings were documented on a detailed "CTE case record form" and were correlated with other investigations like endoscopy, histopathological and microbiological examination, and improvement on empirical therapy to arrive at a final diagnosis. Only confirmed cases of ITB/CD were included for further analysis.

Results

Final diagnoses revealed that 61 patients had ITB, 24 had CD, 90 patients had a final diagnosis not related to ITB/CD, and 125 had no bowel-related diseases. The sensitivity of CTE (ITB vs CD, 90.2 vs 91.6%) was higher than the sensitivity of ileocolonoscopy (ITB vs CD, 87 vs 83.3%). A homogenous pattern of bowel wall thickening and confluent bowel involvement were significantly more common in ITB. Stratified bowel wall thickening with mucosal hyperenhancement, skip lesions in the bowel, and a comb sign were significantly more common in CD. Stratified bowel wall enhancement with an intervening layer of fat was specifically (P < 0.001) seen in patients with CD, and necrotic (P = 0.002) and calcified (P = 0.055) lymph nodes were specifically seen in patients with ITB.

Conclusion

We propose a systematic approach to the radiological differentiation of ITB from CD.

Challenges in the diagnosis and management of inflammatory bowel disease in resource-limited settings in Asia

Inflammatory bowel disease (IBD) is increasing in prevalence in resource-limited settings in Asia. Although the prevalence of IBD is lower in these settings than in high-income countries, the high disease burden due to large population size is projected to overtake that of high-income countries in the near future. Unique challenges exist for diagnosing and managing IBD in Asia. On one hand, the inadequate disease awareness in physicians and the general population, the scarcity of diagnostic services, the infectious mimics of IBD (specifically intestinal tuberculosis), and the widespread use of empirical antibiotics and antitubercular therapy pose diagnostic challenges. On the other hand, the absence of a centralised health-care delivery system or universal health insurance, the high cost of therapy, limited access to biologics, and the high risk of opportunistic infections with immunosuppressive therapy present therapeutic challenges. The high probability of tuberculosis reactivation often precludes biological therapy because Asia is highly endemic for tuberculosis and has a high prevalence of latent tuberculosis. Current screening strategies are often ineffective in ruling out latent tuberculosis. Hence, management strategies are often modified according to these challenges. This Series paper discusses the challenges in the diagnosis and management of IBD in resource-limited settings in Asia.

Defining 'Satisfactory Response' to Therapy in Abdominal Tuberculosis: A Work in Progress

Abdominal tuberculosis is difficult to diagnose due to low sensitivity of microbiological tests and the low histological yield. Satisfactory response to therapy has long been used a criteria for the diagnosis of abdominal tuberculosis. However, the appropriate definitions of response to therapy in abdominal tuberculosis have remained unclear. Recent evidence suggests that mucosal healing of ulcers at the end of therapy or at two months (early mucosal response) is a helpful criteria of response to therapy. This also helps in exclusion of multidrug resistant tuberculosis and alternative diagnosis like Crohn's disease. Further limited literature suggests the use of some biomarkers like C-reactive protein in the follow-up of patients with peritoneal or intestinal tuberculosis.

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.

Is the rise in Crohn's disease in India accompanied by a fall in intestinal tuberculosis? A single-center experience

INTRODUCTION

The relationship between the incidence of intestinal tuberculosis (TB) and Crohn's disease (CD) is interesting, especially considering the striking similarity between the two conditions. Some studies from Asian populations suggested that the incidence of intestinal TB decreases when there is an increase in CD.

AIM

To compare the incidence trend between intestinal TB and CD over 15 years.

METHODS

Medical records of patients seen in the Division of Gastroenterology over 15 years (2005-2019) were reviewed. CD was diagnosed according to the Copenhagen criteria. Intestinal TB was diagnosed in the appropriate clinical situation if any one or more of the following was present: (1) positive TB MGIT culture; (2) positive Gene Xpert for TB; (3) suggestive histologic findings, with positive tissue acid-fast bacillus (AFB) on smear or with sustained response to anti-TB therapy. The incidence time trend of patients with CD and intestinal TB diagnosis was then studied year-wise.

RESULTS

632 medical case records were accessed; 60 patients were excluded due to inadequate data or not fulfilling diagnostic criteria. The 572 patients included 224 with intestinal TB (median age 37 years, IQR 22; 125 [56%] females) and 348 with CD (median age 40 years, IQR 25; 159 [46%] females [p < 0.02 as compared to TB]). Thus, more patients with CD were seen during the study period, but there was no correlation between the incidence of the two conditions (r = 0.318; p = 0.25).

CONCLUSION

In Indian patients in a single private-sector center, there was no inverse correlation between the incidence of intestinal TB and CD over 15 years.

Clinical diagnosis and endoscopic analysis of 10 cases of intestinal tuberculosis

To analyze the clinical characteristics of intestinal tuberculosis (ITB), pay attention to the diagnostic value of endoscopy and mucosal biopsy, improve the recognition of atypical manifestations of ITB under endoscopy, and reduce misdiagnosis and missed diagnosis.The clinical data of 10 patients who were hospitalized in Changzhou second people's Hospital and finally diagnosed as ITB from January 1, 2015 to present were analyzed retrospectively. The basic information, medical history, clinical manifestations and computed tomography (CT), endoscopy of the patients was analyzed retrospectively. The results of pathological examination were analyzed and sorted out.Among the 10 patients, the ratio of male to female was 7:3, 10 (100%) had abdominal pain, 3 (30%) had diarrhea and 2 (20%) had bloody stool. The positive rate of tuberculosis T cell test was 75% (6/8), the diagnostic rate of chest high resolution CT was 60%, and the abnormal rate of abdominal high-resolution CT was 66.7% (6/9). Colonoscopy showed that the lesions mainly involved ileocecum (70%) and ascending colon (60%). Most of the lesions were intestinal stenosis (60%) and circular ulcer (50%). In a few cases, cold abscess (20%) and scar diverticulum (10%). Most of the pathological manifestations were granuloma formation and multinucleated giant cells (60%). The detection rate of caseous granuloma was 20%.The general condition and clinical manifestations of patients with ITB are not specific. Endoscopy and mucosal biopsy are of great significance for its diagnosis. The clinical manifestations and endoscopy of some patients showed atypical signs. Therefore, the combination of multi-disciplinary team models and the enhancement of clinician's recognition of the characteristics of endoscopic examination of ITB can improve us the diagnosis level of ITB.

Prospective validation of CD4+CD25+FOXP3+ T-regulatory cells as an immunological marker to differentiate intestinal tuberculosis from Crohn's disease

Background/Aims

Crohn’s disease (CD) and intestinal tuberculosis (ITB) remain “difficult-to-differentiate” diseases. We have previously documented peripheral blood frequency of CD4⁺ CD25⁺ FOXP3⁺ T-regulatory cells (Treg) as a biomarker to differentiate CD and ITB. We tried to validate these results in a larger cohort of CD and ITB patients.

Methods

Seventy treatment naïve patients of CD (n = 23) and ITB (n = 47) (diagnosed by standard criteria) were recruited prospectively from October 2016 to May 2017. Patients with history of antitubercular therapy in the past were excluded. The frequency of Treg cells in peripheral blood was determined by flow cytometry, and compared between CD and ITB patients.

Results

Similar to our previous study, frequency of Treg cells in peripheral blood was significantly increased in ITB as compared to CD patients (40.9 [interquartile range, 33–50] vs. 24.9 [interquartile range, 14.4–29.6], P<0.001). Further, the receiver operating characteristics curve also showed good diagnostic accuracy with an area under the curve (AUC) of 0.77 (95% confidence interval, 0.65–0.89) and a FOXP3⁺ cutoff value of > 31.3% had a sensitivity and specificity of 83% and 82.6% respectively, to differentiate ITB from CD. Even for the indeterminate cases (n = 33), Treg cell frequency had similar diagnostic accuracy with an AUC of 0.85 (95% confidence interval, 0.68–0.95) and a cutoff of 32.37% had sensitivity and specificity of 87% and 95% respectively, to differentiate ITB from CD.

Conclusions

The current findings validate that the increased frequency of CD4⁺ CD25⁺ FOXP3⁺ Treg in the peripheral blood can be used as a biomarker with high diagnostic accuracy to differentiate ITB from CD.

Pediatric inflammatory bowel disease: Is it really uncommon in Asian children?

Background/Aim

Inflammatory bowel disease (IBD) is said to be rare in Asian children, and there is scarce information from India. We therefore analyzed our experience of pediatric IBD.

Methods

Prospectively maintained data of 105 consecutive children [median age 12 (IQR:7–14) years, 71 males] with IBD from July 2001 through June 2016 were retrospectively analyzed. Their detailed clinical features, endoscopic appearance, histopathology, and treatment outcomes were recorded. For Crohn's disease (CD), disease phenotype and disease location were assessed as per Paris classification.

Results

Disease spectrum includes ulcerative colitis (UC), 55 (52%); CD, 43 (41%); and IBD‐unclassified, 7 (7%). There was a significant increase in the number of cases in the last 5 years compared to the previous 10 years (63 vs. 42, r² = 0.96). Most UC cases (75%) had extensive/pancolitis, 74% of CD had colonic/ileocolonic disease, and 65% had inflammatory phenotype. Fever, growth failure, pain in abdomen, and need for surgery were significantly more frequent in CD than in UC (P < 0.0001). Over a median follow up of 19 (IQR: 7–48) months, remission was achieved in 48 of 51 (94%) UC patients and in 24 of 34 (70.6%) CD patients; an immunomodulator was required to maintain remission in 67% of UC cases. In CD, there was a significant reduction in the use of empirical antitubercular therapy (76%, P = 0.008) with time, and disease progressed in three.

Conclusions

IBD is not uncommon, and the incidence seems to be increasing among Indian children. UC is more common than CD and is more often an extensive disease. CD is mainly an inflammatory phenotype. The majority of children with IBD required an immunomodulator to maintain remission.

Intestinal tuberculosis and Crohn's disease: the importance and difficulty of a differential diagnosis

Tuberculosis (TB) is the most prevalent infection worldwide and affects one third of the population, predominantly in developing countries. Intestinal TB (ITB) is the sixth most frequent extra-pulmonary TB infection. Crohn's disease (CD) is a chronic inflammatory bowel disease that arises from the interaction of immunological, environmental and genetic factors. Due to changes in the epidemiology of both diseases, distinguishing CD from ITB is a challenge, particularly in immunocompromised patients and those from areas where TB is endemic. Furthermore, both TB and CD have a predilection for the ileocecal area. In addition, they share very similar clinical, radiological and endoscopic findings. An incorrect diagnosis and treatment may increase morbidity and mortality. Thus, a great degree of caution is required as well as a familiarity with certain characteristics of the diseases, which will aid the differentiation between the two diseases.