Abdominal tuberculosis in a tertiary care centre in Saudi Arabia.

OBJECTIVES: Abdominal tuberculosis (ATB) is the second most common type of extra-pulmonary tuberculosis. Though it does not usually pose a significant risk of infectivity, ATB can go unidentified and progress to disseminated infection. The aim of this study is to highlight the incidence and outcome of this infection in a tertiary care centre in the Kingdom of Saudi Arabia (KSA). METHODS: In this retrospective study, we included all ATB patients admitted to our centre between January 1 st, 2010 and December 31, 2018. A total of 42 patients with a median age of 49 (range 18-83 years, 78.6% males) were identified. RESULTS: The most common presentation was abdominal pain, weight loss, and abdominal distension. All the patients were HIV negative; however, 50% had a comorbid condition, mainly diabetes mellitus, chronic renal failure, and liver cirrhosis. Tuberculous peritonitis was the predominant type of ATB. Suspicious and potentially malignant abdominal masses appeared on the abdominal CT scans of six patients. This suggest that TB should be excluded in patients from endemic area presenting with abdominal masses. All patients received standard anti-tuberculous medication for an average duration of 7.4 months. The outcome was excellent with 88%% achieving complete response. Adjunctive corticosteroids were not used, and none of the patients had a surgical complication. CONCLUSION: The diagnosis of ATB is challenging. It can mimic inflammatory bowel disease in young populations and malignancy in middle-aged and elderly population. For this reason, a high index of suspicion with prompt treatment is required to improve the prognosis and prevent complications.

CD73 expression in tissue granulomas in distinguishing intestinal tuberculosis from Crohn's disease in a South African cohort.

INTRODUCTION: Overlap of clinical, endoscopic and radiographic features, coupled with a poor microbiological yield makes differentiating Crohn's disease (CD) from intestinal tuberculosis (ITB) challenging. A potential histological differentiating mechanism is the use of immunohistochemical staining for the mesenchymal stem cell marker CD73, as a pilot study showed ITB but not CD granulomas stained positive for this marker. The aim of this study was to assess the value of CD73 in differentiating ITB from CD granulomas in a South African cohort. METHODS: Patients with confirmed CD or ITB were identified from a pathology database. Tissue sections were reviewed by a pathologist to confirm the presence of granulomas. These were then stained with a mouse monoclonal anti-CD73 antibody. The slides were examined together by a pathologist and gastroenterologist in a blinded manner for anti-CD73 staining around granulomas. RESULTS: Ninety six cases were available for analysis; 50 cases of ITB and 46 cases of CD. Thirty percent of CD granulomas (14/46) stained positive for CD73, whereas CD73 positivity was seen in 52% (26/50) of cases of ITB. This was statistically significant (OR 2.48, 95% CI 1.1-5.72, p = .03). The area under the curve (AUC) was 0.61. Sensitivity of CD73 in predicting ITB was 52% and specificity was 70%. Overall CD73 staining of granulomas correctly classified only 60% of cases. CONCLUSIONS: In our study we have shown that significantly more patients with ITB express CD73 in their granulomas than those with CD. However the relatively poor sensitivity, specificity and AUC make this test unlikely to be of value in our clinical practice.

Proteome analysis of the macroscopically affected colonic mucosa of Crohn's disease and intestinal tuberculosis.

Differentiation between intestinal tuberculosis (ITB) and Crohn's disease (CD) is challenging in geographical regions where both these diseases are prevalent. There is a need of biomarkers for differentiation between these two disorders. Colonic biopsies from inflamed mucosa of treatment-naive patients with ITB, CD and controls were used for analysis. Protein extracted from biopsies was digested with trypsin and resulting peptides were labeled with iTRAQ reagents. The peptides were subsequently analyzed using LC-MS/MS for identification and quantification. Gene ontology annotation for proteins was analyzed in PANTHER. Validation experiments were done for six differentially expressed proteins using immunohistochemistry. 533 proteins were identified and 241 proteins were quantified from 5 sets of iTRAQ experiments. While 63 were differentially expressed in colonic mucosa of patients with CD and ITB in at least one set of iTRAQ experiment, 11 proteins were differentially expressed in more than one set of experiments. Six proteins used for validation using immunohistochemistry in a larger cohort of patients; none of them however was differentially expressed in patients with ITB and CD. There are differentially expressed proteins in tissue proteome of CD and ITB. Further experiments are required using a larger cohort of homogeneous tissue samples.

Study of fibrotic complications and hydroxyproline content in mouse liver at different stages of generalized BCG-induced granulomatosis.

Generalized BCG-induced granulomatous was simulated in BALB/c male mice. The number of tuberculous granulomas in the liver and their size as well as the number of hepatocytes showing vacuolar degeneration increased from day 3 to 180 postinfection. Necrotic changes in hepatocytes were most pronounced at the acute phase of inflammation (days 3 to 30). Proliferative processes in the liver parenchyma in the experimental group were less marked than in the control. Increased content of collagen fibers in the liver was determined by excessive collagen synthesis in necrotic areas as well as increased amount of granulomas and fibroblasts. Enhanced proliferative and fibroplastic activity of fibroblasts in granulomas and liver parenchyma was evidently determined by activated granuloma macrophages. These shifts determined changes in the liver content of hydroxyproline during the acute and chronic periods of the disease.

Granulomas of intestinal tuberculosis and Crohn's disease can be differentiated by CD73 cell surface marker expression: a pilot study.

BACKGROUND: Intestinal tuberculosis (ITB) and Crohn's disease are similar granulomatous disorders. Granulomas are present in both and difficult to differentiate on histopathology alone. A recent study demonstrated recruitment of mesenchymal cells (MSCs) at the periphery of granulomas in lymph node tuberculosis which suppressed T cell responses. We hypothesized that granulomas of ITB would also recruit MSCs to evade host immune response. AIM: The purpose of this study was to demonstrate MSC markers in granulomas of ITB and evaluate whether distribution of MSC markers could differentiate between granulomas of Crohn's and ITB. METHODS: We initially retrospectively enrolled 17 patients with confirmed ITB (8) or Crohn's (9) with granulomas on histopathology. Tissues were evaluated by immunofluorescence for MSC markers CD29, CD90, CD73 and absence of haematopoietic markers CD31, CD34, CD45 and CD14. Double-staining was done to confirm presence of MSCs. Subsequently, 23 postoperative specimens of Crohn's (18) and ITB (5) were analyzed for validation. RESULTS: Overall, 27 Crohn's and 13 ITB cases were assessed. CD29 and CD90 positive cells were noted around both ITB and Crohn's granulomas. MSC marker CD73 was expressed around the granulomas of ITB alone and was completely absent in the Crohn's. The subsequent assessment of granulomas in postoperative specimens of Crohn's and ITB also showed similar results. CONCLUSION: Granulomas of ITB and Crohn's disease can be differentiated by CD73 MSC surface marker expression. The differential CD73 expression around ITB granuloma indicates that Mycobacterium tuberculosis evades host immunity by recruiting MSCs with CD73 expression. MSCs with increased CD73 expression could be the future for therapeutic intervention in Crohn's.

Profiling of ABC transporters during active ulcerative colitis and in vitro effect of inflammatory modulators.

BACKGROUND AND AIM: Inflammatory bowel disease is characterized by chronic inflammation of the gastro intestinal tract that manifests as ulcerative colitis and Crohn's disease. Comparative expression profiles of selected ABC transporter genes during active ulcerative colitis and intestinal tuberculosis were studied, and we also investigated the effect of inflammatory modulators on the expression of the transporters in HT-29 cells. METHODS: Using the GEO database, we selected ABC transporter genes that are differentially regulated during active UC and validated the altered expression in biopsies samples by RT-PCR. We also analyzed the effect of inflammatory modulators like TNF-α, lipopolysaccharides (LPS) and drugs (5-ASA, prednisolone and hydrocortisone) on the expression of ABCA1, ABCB8, ABCF2 and ABCC4 using HT-29 cells. RESULTS: We observed significant up-regulation of ABCA1 and ABCA3 while ABCF2, ABCC6, ABCB8 and ABCC4 were down-regulated during UC. ABCC4 was up-regulated in ITB but down-regulated in UC, whereas others showed similar patterns both in UC and ITB. Upon stimulation of HT29 cells by TNF-α, up-regulation of ABCA1, ABCB8, ABCF2 and ABCC4 was seen, and further using inhibitors we found that it was mediated through reactive oxygen species or NF-kB or both. LPS caused a dose dependent and significant down-regulation of ABCB8, ABCF2 and ABCC4 without any effect on ABCA1. The cells treated with drugs 5-ASA, prednisolone and hydrocortisone, exhibited up-regulation of transporters only at a higher dose. CONCLUSION: Altered expression of the above transporters may be associated with the disease. The study also hints at possible mechanisms of differential expression.

Comparative tight junction protein expressions in colonic Crohn's disease, ulcerative colitis, and tuberculosis: a new perspective.

We intended to see the pattern of TJ protein expression along with ultrastructural changes in colonic biopsies from patients with Crohn's disease (CD), ulcerative colitis (UC), and tuberculosis (cTB). Colonic biopsies from 11 patients with active CD and ten patients each with active UC and untreated cTB were taken along with biopsies from six patients with irritable bowel syndrome as controls. These were evaluated for expression pattern of key TJ proteins which included claudin-2 as TJ pore-forming protein, claudin-4 as pore-sealing protein, ZO-1 as scaffold protein, and occludin as TJ protein related to cell migration and polarity. Claudin-2 expression was upregulated along the whole length of intercellular junction (ICJ) in biopsies from patients with active CD and UC in comparison to the biopsies from cTB patients and controls, where its expression was limited to the uppermost part of ICJ. There was reduced expression of ZO-1 in UC, CD, and cTB. On transmission electron microscopic examination, the pentalaminar structure of TJs was destroyed in patients with CD and UC but no significant change was seen in those with cTB and in controls. The expression of claudin-2 was distinctly different in active CD and UC in comparison to its expression pattern in patients with cTB and in controls. The redistribution of claudin-2 expression was in accordance with the TJ ultrastructural changes in patients with UC, CD, and cTB. Altered claudin-2 expression, along with destroyed TJs, may result in loss of selective permeability in patients with UC and CD.

Chronic intestinal Mycobacteria infection: discrimination via VOC analysis in exhaled breath and headspace of feces using differential ion mobility spectrometry.

Differential ion mobility spectrometry (DMS) is a method to detect volatile organic compounds (VOC) in the ppt range. This study assessed whether VOC analysis using DMS could discriminate subjects with an experimentally induced chronic intestinal infection caused by Mycobacteria from non-infected controls. The animal model consisted of two groups of goats orally infected with two different doses of Mycobacterium avium subspecies paratuberculosis (MAP) and one group of non-infected healthy controls (each group: n = 6). Using DMS, exhaled breath and headspace of feces were analyzed on-line on an individual basis 9 months after inoculation of MAP. Data analysis included peak detection, cluster analysis, selection of discriminating VOC features (Mann-Whitney U test), and classification using a support-vector-machine. Taking the background of ambient air conditions into account, VOC analysis of exhaled breath as well as of feces revealed significant differences between chronically infected animals and non-infected controls. In both specimens, increasing as well as decreasing VOC features could be attributed to infection. Discrimination between infected and non-infected animals was sharper analyzing exhaled breath compared to headspace of feces. In exhaled breath, at least two VOC features were found to increase in a dose-dependent manner with increasing doses of MAP inoculated. Results of this study provide strong evidence that DMS analysis of exhaled breath has the potential to become a valuable tool for non-invasive assessment of VOC specifically related to certain diseases or infections.

Salivary levels of isoniazid and rifampicin in tuberculous patients.

Concentrations of isoniazid and rifampicin were determined in time-matched samples of saliva and serum from 30 tuberculous patients (18 with pulmonary tuberculosis and 12 with intestinal tuberculosis), comprising 18 slow and 12 rapid acetylators of isoniazid, following administration of isoniazid 300 mg and rifampicin 12 mg/kg. The diffusion of isoniazid into saliva was quite rapid and the salivary concentrations were similar to those in serum, suggesting that saliva could be used in place of serum for all pharmacokinetic studies with isoniazid. The salivary concentrations of rifampicin were much lower than those in serum, the mean peak concentrations being 0.9 and 8.5 microgram/ml, respectively. Further, there was evidence of a significant delay in the diffusion of rifampicin from serum to saliva.

Theophylline-isoniazid interaction.

Drugs influencing hepatic microsomal enzyme systems, such as isoniazid, may affect the elimination pattern of theophylline. The case reported here refers to an adult female patient with a history of chronic asthma and intestinal tuberculosis who, during isoniazid therapy, presented with theophylline plasma concentrations above the therapeutic range and developed toxic symptoms. The initial episode of theophylline toxicity occurred after one month of coadministering isoniazed 300 mg/d and theophylline 350 mg bid. The theophylline plasma concentration during this episode was 24.1 micrograms/mL and was associated with the typical symptoms of theophylline toxicity. Rechallenge with isoniazide 300 mg/d and theophylline 400 mg bid showed a progressive increase in trough morning theophylline plasma levels, reaching a toxic concentration of 25.1 micrograms/mL on day 55. After withdrawal of isoniazid, theophylline concentrations gradually declined, reaching 12.9 micrograms/mL in 35 days. Theophylline toxicity in this patient might have been induced by chronic administration of isoniazid.

A study of malabsorption in intestinal tuberculosis: stagnant loop syndrome.

A study was carried out in the patients with intestinal tuberculosis and obstruction requiring surgery to determine the pathogenesis of malabsorption in this condition. Fifteen of the 20 patients studied had malabsorption, nine of 17 (53%) had intestinal bacterial overgrowth and 10 of 16 (62.6%) had free bile acids in their jejunal aspirates. In a comparable group of nontuberculus intestinal obstruction requiring surgery, six of seven (85.7%) had malabsorption, and four of five (80%) had both the bacterial overgrowth as well as bile salt deconjugation. Among a group of 10 patients with intestinal tuberculosis without significant obstruction, four were found to have malabsorption but only one had evidence of bacterial overgrowth and bile salt deconjugation. In contrast, only one of the 10 patients with extraintestinal tuberculosis and none of the 12 healthy, normal subjects had malabsorption. None had bacterial overgrowth or bile salt deconjugation in either group. Resection of the obstructing lesion corrected the malabsorption as well as the bacterial overgrowth and the bile salt deconjugation in all four patients tested with intestinal tuberculosis. Malabsorption in intestinal tuberculosis thus appears to be associated with obstruction rather than with the tuberculous process. Demonstration of bacterial overgrowth and bile salt deconjugation in the upper small intestine of patients with intestinal tuberculosis with obstruction and malabsorption indicate the presence of a stagnant loop syndrome.

Fecal excretion of bile acids: a new technique for studying bile acid kinetics in patients with ileal resection.

The fecal elimination and enterohepatic circulation of bile acid was studied in 11 patients. 10 patients with varying degrees of ileal disease or resection and 1 patient with pancreatic insufficiency and no ileal disease. A new technique was employed which involved the nearly simultaneous administration of cholic acid-(14)C and a nonabsorbable marker. (51)CrCl(3). Each individual stool specimen was collected for 36-96 hr and analyzed separately. Assay of the radioactivity of each isotope allowed the accurate determination of an excretion rate for both cholic acid and (51)Cr. The difference between these rates was used to calculate an absorption coefficient for cholic acid. In addition, bile acid concentration measured by the steroid dehydrogenase technique, and the water content of each stool was determined. THE PATIENTS WERE DIVIDED INTO GROUPS DEPENDING UPON HOW MUCH SMALL INTESTINE WAS RESECTED OR DISEASED: six patients with less than 100 cm of ileal resection or disease (group A), and five patients with more than 100 cm of ileal disease or resection (group B). The (51)Cr excretion rate was similar in the two groups, but cholic acid-(24)C excretion rates were significantly more rapid in group B than in group A. The cholic acid absorption coefficient was essentially normal in the patient with pancreatic insufficiency, moderately decreased in group A patients, and extremely low or zero in group B patients. It was inversely related to the length of intestine diseased or resected. Daily fecal bile acid excretion was normal to twice normal in group A patients and 2-8 times normal in group B patients. In all patients with ileal disease or resection, there was a direct correlation between fecal bile acid, fecal mass, and fecal water. Each millimole of additional bile acid in the stool was associated with an increase in stool water of 11 moles (P < 0.01). These studies show that the kinetics of bile acids in the enterohepatic circulation can be accurately studied in patients with extensive ileal resection. The regular relationship between fecal bile acid and fecal mass and water suggests, but does not prove, a critical role of bile acid in determining stool water.