Immunohistochemistry and real-time Polymerase Chain Reaction: importance in the diagnosis of intestinal tuberculosis in a Peruvian population.

INTRODUCTION: The diagnosis of intestinal tuberculosis is challenging even nowadays. This study aims to report the positivity rates of new diagnostic methods such as immunohistochemistry and Real-Time Polymerase Chain Reaction in patients with intestinal tuberculosis, as well as describe the pathological and endoscopic features of intestinal tuberculosis in our population. METHODS: This was a retrospective observational study conducted in patients diagnosed with intestinal tuberculosis, between 2010 to 2023 from the Hospital Nacional Daniel Alcides Carrion and a Private Pathology Center, both located in Peru. Clinical data was obtained, histologic features were independently re-evaluated by three pathologists; and immunohistochemistry and real-time Polymerase Chain Reaction evaluation were performed. The 33 patients with intestinal tuberculosis who fulfilled the inclusion criteria were recruited. RESULTS: Immunohistochemistry was positive in 90.9% of cases, while real-time Polymerase Chain Reaction was positive in 38.7%. The ileocecal region was the most affected area (33.3%), and the most frequent endoscopic appearance was an ulcer (63.6%). Most of the granulomas were composed solely of epithelioid histiocytes (75.8%). Crypt architectural disarray was the second most frequent histologic finding (78.8%) after granulomas, but most of them were mild. CONCLUSION: Since immunohistochemistry does not require an intact cell wall, it demonstrates higher sensitivity compared to Ziehl-Neelsen staining. Therefore, it could be helpful for the diagnosis of paucibacillary tuberculosis.

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.

Clinicopathological profile of gastrointestinal tuberculosis: a multinational ID-IRI study.

Data are relatively scarce on gastro-intestinal tuberculosis (GITB). Most studies are old and from single centers, or did not include immunosuppressed patients. Thus, we aimed to determine the clinical, radiological, and laboratory profiles of GITB. We included adults with proven GITB treated between 2000 and 2018. Patients were enrolled from 21 referral centers in 8 countries (Belgium, Egypt, France, Italy, Kazakhstan, Saudi Arabia, UK, and Turkey). One hundred four patients were included. Terminal ileum (n = 46, 44.2%), small intestines except terminal ileum (n = 36, 34.6%), colon (n = 29, 27.8%), stomach (n = 6, 5.7%), and perianal (one patient) were the sites of GITB. One-third of all patients were immunosuppressed. Sixteen patients had diabetes, 8 had chronic renal failure, 5 were HIV positive, 4 had liver cirrhosis, and 3 had malignancies. Intestinal biopsy samples were cultured in 75 cases (78.1%) and TB was isolated in 65 patients (86.6%). PCR were performed to 37 (35.6%) biopsy samples and of these, 35 (94.6%) were positive. Ascites samples were cultured in 19 patients and M. tuberculosis was isolated in 11 (57.9%). Upper gastrointestinal endoscopy was performed to 40 patients (38.5%) and colonoscopy in 74 (71.1%). Surgical interventions were frequently the source of diagnostic samples (25 laparoscopy/20 laparotomy, n = 45, 43.3%). Patients were treated with standard and second-line anti-TB medications. Ultimately, 4 (3.8%) patients died and 2 (1.9%) cases relapsed. There was a high incidence of underlying immunosuppression in GITB patients. A high degree of clinical suspicion is necessary to initiate appropriate and timely diagnostic procedures; many patients are first diagnosed at surgery.

How can gastro-intestinal tuberculosis diagnosis be improved? A prospective cohort study.

BACKGROUND: Gastrointestinal tuberculosis (TB) is diagnostically challenging; therefore, many cases are treated presumptively. We aimed to describe features and outcomes of gastrointestinal TB, determine whether a clinical algorithm could distinguish TB from non-TB diagnoses, and calculate accuracy of diagnostic tests. METHODS: We conducted a prospective cohort study of hospitalized patients in Kota Kinabalu, Malaysia, with suspected gastrointestinal TB. We recorded clinical and laboratory characteristics and outcomes. Tissue samples were submitted for histology, microscopy, culture and GeneXpert MTB/RIF®. Patients were followed for up to 2 years. RESULTS: Among 88 patients with suspected gastrointestinal TB, 69 were included in analyses; 52 (75%) had a final diagnosis of gastrointestinal TB; 17 had a non-TB diagnosis. People with TB were younger (42.7 versus 61.5 years, p = 0.01) and more likely to have weight loss (91% versus 64%, p = 0.03). An algorithm using age < 44, weight loss, cough, fever, no vomiting, albumin > 26 g/L, platelets > 340 × 109/L and immunocompromise had good specificity (96.2%) in predicting TB, but very poor sensitivity (16.0%). GeneXpert® performed very well on gastrointestinal biopsies (sensitivity 95.7% versus 35.0% for culture against a gold standard composite case definition of confirmed TB). Most patients (79%) successfully completed treatment and no treatment failure occurred, however adverse events (21%) and mortality (13%) among TB cases were high. We found no evidence that 6 months of treatment was inferior to longer courses. CONCLUSIONS: The prospective design provides important insights for clinicians managing gastrointestinal TB. We recommend wider implementation of high-performing diagnostic tests such as GeneXpert® on extra-pulmonary samples.

[Gastric tuberculosis in an elderly patient:a case report].

A woman in her 70s presented to our hospital with epigastric pain, back pain, and weight loss. Esophagogastroduodenoscopy was performed, and numerous protuberances, which were suspected to be submucosal tumors, were found at the gastric corpus. The patient was diagnosed with gastric tuberculosis based on the biopsy results of these protuberances. Histopathological analysis demonstrated non-caseating epithelioid granuloma. A positive culture for Mycobacterium tuberculosis was also obtained on gastric juice analysis and confirmed using polymerase chain reaction assay. In the rapidly aging population in Japan, our findings emphasize on the importance of differentiating gastrointestinal tuberculosis, including gastric tuberculosis, from other diseases. This case may provide information about the development of gastric tuberculosis.

Intestinal tuberculosis: a diagnostic challenge.

OBJECTIVE: To describe characteristics, presentation, time to diagnosis and diagnostic findings of patients with intestinal tuberculosis (ITB) in a low-burden country. METHOD: Retrospective study of 61 consecutive ITB patients diagnosed between 2008 and 2014 at a large East London hospital. RESULTS: Forty of sixty-one patients were male. Mean age was 34.6 years. 93% of patients were born abroad, mostly from TB-endemic areas (Indian subcontinent: 88%, Africa: 9%). 25% had concomitant pulmonary TB. Median time from symptom onset to ITB diagnosis was 13 weeks (IQR 3-26 weeks). Ten patients were initially treated for IBD, although patients had ITB. The main sites of ITB involvement were the ileocaecum (44%) or small bowel (34%). Five patients had isolated perianal disease. Colonoscopy confirmed a diagnosis of ITB in 77% of those performed. 42 of 61 patients had a diagnosis of ITB confirmed on positive histology and/or microbiology. CONCLUSION: Diagnosis of ITB is often delayed, which may result in significant morbidity. ITB should be excluded in patients with abdominal complaints who come from TB-endemic areas to establish prompt diagnosis and treatment. Diagnosis is challenging but aided by axial imaging, colonoscopy and tissue biopsy for TB culture and histology.

Esophageal tuberculosis with coexisting opportunistic infections in a renal allograft transplant recipient.

We report a renal allograft transplant recipient with esophageal tuberculosis (TB) coinfected with herpes simplex virus (HSV) and Candida. The patient presented with oropharyngeal candidiasis and was started on fluconazole. Upper gastrointestinal endoscopy showed whitish patches with mucosal ulcers in the esophagus. Histopathological examination confirmed TB and HSV infection. The patient recovered after antiviral, antifungal, and anti-tubercular therapy with reduction in immunosuppression. In a TB-endemic zone, TB can coexist with opportunistic infections in an immunocompromised host.

Tubercular Intestinal Strictures Show a Poor Response to Anti-Tuberculous Therapy.

BACKGROUND: The literature on resolution of intestinal strictures in patients with intestinal tuberculosis (ITB) after anti-tuberculous therapy (ATT) is sparse and ambivalent. We aimed to assess the frequency of stricture resolution after ATT and its predictors. METHODS: This ambispective cohort study included consecutive ITB patients with strictures who received ATT for ≥6 months and were on regular follow-up between January 2004 and December 2015. Resolution of stricture was assessed at the end of ATT by endoscopy/radiology. RESULTS: Of 286 patients, 128 had strictures, and 106 were finally included (63 males, median age 35 years). The stricture location was distal ileum/ileocecal in 52 (49.1%), colon in 37 (34.9%), ileocolonic in 4 (3.8%), proximal small bowel in 10 (9.4%), and gastroduodenal in 4 (3.8%) patients. Although all patients demonstrated mucosal healing (indicating resolution of active infection), stricture resolution occurred only in 25/106 (23.6%) patients. Symptoms pertaining to stricture (pain abdomen/recurrent SAIO) were present in 104/106 (98%) patients, and after a median of 6 (6-9) months of ATT, these symptoms resolved only in half, 88% (22/25) in patients with stricture resolution and 38% (30/79) in patients with persistent strictures. Colonic strictures had the least resolution (5.4%) followed by proximal small intestinal (20%) and distal ileal/ileocecal (36.5%). Although not statistically significant, stricture resolution was less frequent in patients with multiple strictures, longer strictures (>3 cm), and strictures in which scope was not negotiable prior to ATT. CONCLUSION: Only one-fourth of ITB patients with strictures show resolution of stricture following ATT. The resolution of strictures is dependent on disease location, and majority of them exhibit symptoms pertaining to stricture even after ATT.

Endoscopic ultrasound in diagnosis of esophageal tuberculosis: 10-year experience at a tertiary care center.

Definite diagnosis of esophageal tuberculosis (ET) requires isolation of tubercle bacilli, which is challenging in clinical practice. Difficulty in differentiating ET from other esophageal diseases may well result in a delay in diagnosis. The literature on utility of endoscopic ultrasound (EUS) in diagnosis of ET is insufficient. This study aims to evaluate the role of EUS morphology combined with EUS-guided tissue acquisition in the diagnosis of ET. Data of the 35 patients diagnosed with ET from January 2006 to October 2015 were retrospectively analyzed. After miniprobe and linear echoendoscopic visualization, either linear EUS-guided deep biopsy or EUS-guided fine needle aspiration was performed for tissue acquisition. Histocytopathological results showing caseous necrosis or acid fast bacilli (AFB) or epithelioid granuloma were considered diagnostic. Esophageal wall thickening or mass formation with disruption of the adventitia due to infiltration by adjacent mediastinal lymphadenopathy was typically observed under EUS. Tissue acquisition revealed epithelioid granuloma in 33 patients, caseous necrosis in 13, a positive AFB stain in 14, and nonspecific chronic inflammation in 2. Of the 35 patients, 33 (94.3%) with both characteristic EUS morphology and diagnostic histocytopathology were considered to have an EUS established diagnosis. The remaining two with only nonspecific chronic inflammation received empirical antitubercular chemotherapy based solely on EUS morphology. The two-year follow-up confirmed diagnosis of ET in all patients. While the final diagnosis of ET was based upon two-year follow-up of treatment response to antitubercular medication in addition to caseous necrosis/granuloma/positive-AFB stain revealed by EUS-guided tissue acquisition, an EUS-established diagnosis of ET and medical treatment with long-term follow-up is rational and practical compared with surgery or untreated follow-up.

Abdominal Tuberculosis.

Abdomen is involved in 11% of patients with extra-pulmonary tuberculosis; The most common site of involvement is the ileocaecal region, other locations of involvement, in order of descending frequency, are the ascending colon, jejunum, appendix, duodenum, stomach, oesophagus, sigmoid colon, and rectum. Apart from the basic work up, Investigations like CT scan, EUS, Capsule endoscopy, Balloon enteroscopy, Ascitic fluid ADA, TB-PCR, GeneXpert, Laproscopy are being increasingly used to diagnose tuberculosis.Therapy with standard antituberculous drugs is usually highly effective for intestinal TB. Six-months therapy is as effective as nine-months therapy. Multi-Drug Resistance (MDR) has been observed in 13% of MTB isolates. The development of Drug Induced Hepatotoxicity (DIH) during therapy for TB is the most common reason leading to interruption of therapy. There are various guidelines for the management of TB post DIH. Surgery is usually reserved for patients who have developed complications or obstruction not responding to medical management.

Clinico-Pathological Profile and Surgical Outcome of Patients of Gastrointestinal Tuberculosis Undergoing Laparotomy.

Tuberculosis is one of the earliest diseases affecting the mankind. Abdominal tuberculosis constitutes a common public health issue in developing countries like ours. Gastrointestinal tuberculosis often involves the ileocecal region. Surgery in case of abdominal tuberculosis is required to overcome the deleterious effects of the disease like tissue disorganization, obstruction and perforatio. AIMS AND OBJECTIVES: 1. To study the various clinical profiles of gastrointestinal tuberculosis in patients undergoing laparotomy; 2. To study the surgical pathology of gastrointestinal tuberculosis; 3. To study the various surgical treatment modalities based upon the intraoperative findings and its outcome. Results: This is a prospective study over 12 months at Himalayan Institute of Medical Sciences, SRHU, Swami Ram Nagar, Dehradun. This study was done to study the clinic-pathological profile of gastrointestinal tuberculosis undergoing laparotomy. Incidence of gastro intestinal tuberculosis was seen highest in age group 15 to 25 years with male predominance. Most commonly presentation being intestinal obstruction with ileo-caecal as the most common area involved and right hemicolectomy as the commonest procedure done. Common surgical pathologies were ileo-caecal mass and ileal perforation and this also has relation to pulmonary tuberculosis. CONCLUSION: Inspite of specific antituberculous drugs and vast measures against the disease, including chemoprophylaxis and pasteurisation abdominal tuberculosis remains a fairly common disease even today. Gastrointestinal tuberculosis has an indolent course and the common mode of presentation is usually sub acute or chronic. Prompt surgical exploration, vigilant postoperative care and administration of ATD helped to treat the patients successfully with their complete cure and rehabilitation.

Severe hypercholesterolemia mediated by lipoprotein X in a patient with cholestasis.

Lipoprotein X (LpX) is an abnormal lipoprotein associated with cholestasis. It is a significant cause of severe hypercholesterolemia and should always be considered in patients with cholestatic liver disease. This case highlights the significance of LpX as a cause of severe hypercholesterolemia in a patient with cholestasis secondary to a granulomatous hepatitis attributed to tuberculosis. Lipoprotein agarose gel electrophoresis and gradient gel electrophoresis were performed for the detection of LpX. The liver function tests, electrolytes, lipid profile and bile acids were also determined. Anti-tuberculous therapy was initiated and the liver functions improved with normalisation of the lipid profile.

[Detection of Mycobacterium tuberculosis complex in paraffin-embedded tissues by real-time fluorescent quantitative polymerase chain reaction].

OBJECTIVE: To investigate the feasibility of real-time fluorescent quantitative (qPCR) assay in detecting mycobacterium tuberculosis complex (MTB) in paraffin embedded tissues for diagnostic purpose. METHODS: Using qPCR assay, 1000 consecutive formalin-fixed and paraffin embedded (FFPE) tissues (from 2011 to 2012) suspected of MTB infection were tested by amplifying the MTB specific insertion sequence 6110 (IS6110). The specificity of the PCR product was confirmed by Sanger sequencing as compared with the MTB genomic DNA of the IS6110 sequence. Tissues with Ziehl-Neelsen acid-fast staining were used as control. RESULTS: In the 1000 samples, 513 were positive for mycobacterium by Ziehl-Neelsen acid-fast staining (detection rate 51.3%); whereas 546 were MTB positive by qPCR assay (detection rate 54.6%). Concordance rate for both assays was 73.1%. The diagnosis rate increased by 14.4% by combinination of Ziehl-Neelsen acid-fast staining and qPCR results. More interestingly, by analyzing the Ziehl-Neelsen acid-fast staining and qPCR results three cases of M.leprae infection and four cases of non-tuberculous Mycobacterium (NTM) infection were identified. CONCLUSIONS: qPCR detection of MTB in FFPE tissue is more sensitive than Ziehl-Neelsen acid-fast staining assay. Combination of these two assays can increase the detection rate and also identify some rare cases of NTM infection.

[The symptoms and surgical tactics for complicated forms of the abdominal cavity tuberculosis].

The results of treatment of 12 patients, suffering complicated forms of abdominal tuberculosis and external intestinal fistulas, were presented. Late diagnosis of abdominal tuberculosis in the patients, suffering the complications phase of the disease, is caused by unclear symptoms presence in early stages of the disease. Clinical and laboratory indices in peritonitis of a phthisis origin are nonspeciphic. In 91% of patients, admitted to the hospital for complicated forms of abdominal tuberculosis and external intestinal fistulas, the operative treatment was indicated. Surgical intervention (more frequently right-sided hemicolectomy, enterostomy, the abscesses opening, the caseously-changed lymph nodes excision, formation of anastomosis) was performed in 11 patients for peritonitis and external intestinal fistulas. The method of a secure invagination anastomoses formation was elaborated, permitting to perform primary restoration operations. An early diagnosis, early effective therapy and radical surgical intervention conduction for complicated abdominal tuberculosis promote the patients to survive.

Recent updates in diagnosis of abdominal tuberculosis with emphasis on nucleic acid amplification tests.

INTRODUCTION: Abdominal tuberculosis (TB) is a common epitome of extrapulmonary TB (EPTB), wherein peritoneal and intestinal TB are the most prevalent forms. Diagnosis of abdominal TB is a daunting challenge owing to variable anatomical locations, paucibacillary nature of specimens and atypical clinical presentations that mimic other abdominal diseases, such as Crohn's disease and malignancies. In this review, we made a comprehensive study on the diagnosis of abdominal TB. AREA COVERED: Various modalities employed for abdominal TB diagnosis include clinical features, imaging, bacteriological tests (smear/culture), histopathological/cytological observations, interferon-gamma release assays and nucleic acid amplification tests (NAATs). Among NAATs, loop-mediated isothermal amplification assay, PCR, multiplex-PCR, nested PCR, real-time PCR and GeneXpert® MTB/RIF were discussed. Identification of circulating Mycobacterium tuberculosis cell-free DNA by real-time PCR within ascitic fluids is another useful approach. EXPERT OPINION: Several novel molecular/immunological methods, such as GeneXpert Ultra, aptamer-linked immobilized sorbent assay, immuno-PCR (I-PCR) and nanoparticle-based I-PCR have recently been developed for detecting pulmonary TB and several EPTB types, which may also be explored for abdominal TB diagnosis. Precise and prompt diagnosis of abdominal TB may initiate an early therapy so as to reduce the complications, i.e. abdominal pain, ascites, abdominal distension, intestinal obstruction/perforation, etc., and avoid surgical involvement.Plain Language SummaryAbdominal tuberculosis (TB) is a manifestation of extrapulmonary TB (EPTB), where peritoneal and intestinal TB are two major forms. Diagnosis of abdominal TB is difficult owing to low bacterial load present in clinical samples and non-specific clinical presentations as it mimics other diseases such as inflammatory bowel diseases, abdominal malignancies, etc. Bacteriological tests (smear/culture) almost fail owing to poor sensitivities and it is not always possible to get representative tissue samples for histopathological and cytological observations. In recent years, molecular tests i.e. nucleic acid amplification tests (NAATs), such as PCR/multiplex-PCR (M-PCR), nested PCR and GeneXpert are widely employed. Markedly, PCR/M-PCR and nested PCR exhibited reasonable good sensitivities/specificities, while GeneXpert revealed low sensitivity in most of the studies but high specificity, thus it could assist in differential diagnosis of intestinal TB and Crohn's disease. Further, novel molecular/immunological tests employed for pulmonary TB and other EPTB types were described and those tests can also be utilized to diagnose abdominal TB. Reliable and rapid diagnosis of abdominal TB would initiate an early start of anti-tubercular therapy and reduce the severe complications.

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.

Gastrointestinal tuberculosis in renal transplant recipients: case report and review of the literature.

Mycobacterium tuberculosis is an important opportunistic pathogen following renal transplantation and is often associated with adverse outcomes. Gastrointestinal tuberculosis (GITB) is an infrequent manifestation of TB but a potentially lethal one. We present a case of a renal allograft recipient with GITB 18 months after transplant and review other published cases to identify the typical presenting symptoms, risk factors, and natural history. Treatment of GITB is also discussed.