Primary adenocarcinoma of colon: A clinicopathological study with the prevalence and correlation of CDX2 biomarker expression - A tertiary care center experience.

BACKGROUND: Colorectal cancer is one of the alarming health problems worldwide. Prognostic biomarkers are the key for risk stratification in patients with colon cancer and the decision to recommend adjuvant chemotherapy. It has been difficult to identify a single prognostic biomarker for colon cancer. Currently, tumor stage, tumor grade, and microsatellite instability remain the most important prognostic variables that aid in the treatment of patients with colon cancer. Some studies highlighted that CDX2 immunohistochemistry negativity is an independent prognostic factor and indicates a worse survival rate. Our aim was to study the prevalence of CDX2 biomarker expression in patients diagnosed with primary adenocarcinoma and to correlate this with the clinical profile and pathological features. METHODS: Endoscopic mucosal biopsies and resection specimens of 148 patients diagnosed with colonic adenocarcinoma were analyzed. CDX2 immunohistochemistry was performed, and the result was correlated with clinicopathological features. The results were presented as mean, frequencies, and percentages. Pearson's Chi-square test was used to assess the associations between clinicopathological parameters and CDX2 immunohistochemistry negativity. RESULTS: The prevalence of CDX2 expression by immunohistochemistry in colon cancer was found to be 92%. CDX2 biomarker negativity was found to be higher in left-sided colon cancers, poorly differentiated adenocarcinoma, mucinous carcinoma, and higher TNM stages. CONCLUSION: CDX2-negative tumors are often associated with several adverse prognostic variables (e.g., advanced stage, poor differentiation, and metastasis). Thus, sub-classification of colon cancer based on the CDX2 biomarker aids to separate them into prognostically relevant categories.

Granulomatous inflammation is less common in delayed-onset Crohn's disease.

Crohn's disease (CD) usually affects younger individuals but delayed-onset disease is not uncommon. We studied the epidemiology, demographic profile, and clinical characteristics of patients with delayed-onset CD (disease onset >50 years) and compared them with CD in younger individuals (disease onset 20-40 years) in a tertiary care center in India. The presenting symptoms, site of involvement, and treatment profile were similar, except for weight loss, which was more often noted in young-onset CD. However, granulomatous inflammation on mucosal biopsy was twice as common in young-onset compared to delayed-onset CD. As it is thus seen less often in delayed-onset CD, this may lead to a potential delay in diagnosis and treatment.

Image-enhanced endoscopy for real-time differentiation between hyperplastic and fundic gland polyps in the stomach.

BACKGROUND: Fundic gland polyps (FGP) of stomach are benign, while some hyperplastic polyps (HP) may harbor dysplasia or malignancy. Conventional white light endoscopy (WLE) cannot reliably distinguish FGP from HP. We investigated the role of image-enhanced endoscopy in differentiating FGP from HP. METHODS: Patients with gastric polyps were recruited prospectively. The characteristics of the polyps were assessed using WLE and magnification narrow band imaging (mNBI). The microsurface, intervening space (IS), and microvascular (V) features of polyps were evaluated on mNBI. The pattern characteristic of FGP and HP were determined. Histopathology of polyps was the gold standard for diagnosis. Finally, in the validation phase, five endoscopists applied the characteristic features identified in this study to predict the type of gastric polyp and their performance was assessed. RESULTS: Forty-five patients with a total of 70 gastric polyps (HP-46, FGP-24) were included in this study. On mNBI, the pattern characteristic of HP included peripheral curved type of white structures forming large circular/villous loops (microsurface), enlarged intervening space, and microvessels appearing as dark patches in the intervening space (p<0.001 vs. FGP). These were noted in 95.7% HP. In contrast, 95.8% FGP had a pattern characterized by dotted/elliptical/tubular white structures (microsurface), normal width of intervening space, and microvessels surrounding the white structures in a network pattern. This IS-V pattern classification had an accuracy of >90% in the validation phase with intra-class correlation coefficient of 0.95. The accuracy of mNBI was higher than WLE (97.1% vs. 67%) in predicting the type of gastric polyp. CONCLUSIONS: Image-enhanced endoscopy with mNBI (IS-V pattern) performs very well in differentiating HP from FGP.

Lack of Association of Helicobacter pylori in Laryngeal Pathologies.

To study the association of Helicobacter pylori (H. pylori) in patients with laryngeal pathologies. Study design: prospective observational study. Tertiary care teaching hospital. One hundred consecutive patients with laryngeal lesions scheduled for microlaryngoscopy were enrolled in the study. Laryngopharyngeal reflux was assessed using the reflux symptom index and reflux finding score. Tissue samples from the laryngeal lesions were taken under general anaesthesia and were screened for the presence of H. pylori using real time polymerase chain reaction (PCR) for ureA genes and histopathological examination. Of the 100 patients, 14 had a significant reflux symptom index score and 35 had significant reflux finding score. The lesions in the study subjects included both benign and malignant laryngeal pathologies. Vocal cord polyps formed more than half of the laryngeal pathology (57%) studied. Our study could not detect H. pylori in any laryngeal lesions by PCR analysis and histopathological examination. H. pylori may not be associated with laryngeal pathologies.

Common polymorphisms of protein tyrosine phosphate non-receptor type 2 gene are not associated with risk of Crohn's disease in Indian.

BACKGROUND: Multiple genetic risk factors for Crohn's disease (CD) have been identified. However, these observations are not consistent across different populations. The protein tyrosine phosphate non-receptor type 2 (PTPN2) gene plays a role in various aspects of host defense including epithelial barrier function, autophagy, and innate and adaptive immune response. Two common polymorphisms in the PTPN2 gene (rs2542151 and rs7234029) have been associated with risk of CD in Western countries. AIM: To evaluate the association of PTPN2 gene polymorphisms with risk of CD in Indian population. METHODS: We conducted a prospective case-control study. Patients with CD were recruited, and their clinical and investigation details were noted. Controls were patients without organic gastrointestinal disease or other comorbid illnesses. Two common polymorphisms in the PTPN2 gene (rs2542151 and rs7234029) were assessed. DNA was extracted from peripheral blood samples of cases and controls and target DNA was amplified using specific sets of primers. The amplified fragments were digested with restriction enzymes and the presence of polymorphism was detected by restriction fragment length polymorphism. The frequency of alleles was determined. The frequencies of genotypes and alleles were compared between cases and controls to look for significant differences. RESULTS: A total of 108 patients with CD (mean age 37.5 ± 12.7 years, females 42.6%) and 100 controls (mean age 39.9 ± 13.5 years, females 37%) were recruited. For the single nucleotide polymorphism (SNP) rs7234029, the overall frequency of G variant genotype (AG or GG) was noted to be significantly lower in the cases compared to controls (35.2% vs 50%, P = 0.05). For the SNP rs2542151, the overall frequency of G variant genotype (GT or GG) was noted to be similar in cases compared to controls (43.6% vs 47%, P = 0.73). There were no significant differences in minor allele (G) frequency for both polymorphisms between the cases and controls. Both the SNPs had no significant association with age of onset of illness, gender, disease location, disease behaviour, perianal disease, or extraintestinal manifestations of CD. CONCLUSION: Unlike observation form the West, polymorphisms in the PTPN2 gene (rs7234029 and rs2542151) are not associated with an increased risk of developing CD in Indian patients.

Comparison of Magnetic Resonance Enterography Global Score (MEGS) with indices of Crohn's disease activity in South Asian population.

PURPOSE: Assessment of disease activity in Crohn's helps predict important clinical outcomes. Among the various modalities available to assess disease activity, magnetic resonance enterography (MRE) is considered a safe and reliable imaging option. Various MRE-based scoring systems have been developed to measure disease activity, one of which being the MRE global score (MEGS). We aimed to correlate MEGS with some of the important indices of Crohn's disease activity. METHODOLOGY: Crohn's disease patients referred for MRE were included in the study. Along with demographic profile and relevant investigations, MRE parameters related to MEGS were also assessed. RESULT: A total of 47 patients were recruited for the study. Their median age was 34 years (range 18-68 years), and male:female ratio was 16:31. There was modest positive correlation between MEGS and faecal calprotectin (r = 0.3, p = 0.04), CRP level (r = 0.34, p = 0.02) and Harvey Bradshaw index (r = 0.3, p = 0.043), respectively. However, there was strong correlation between segmental MEGS and Simple Endoscopic Score in those with terminal ileal disease (r = 0.81, p < 0.001). Mural thickness was the only MRE parameter that correlated with active disease (OR - 1.35, 95% CI 1.01, 1.81, p = 0.041) on multivariate analysis. There was moderate inter-observer agreement (Lin's r = 0.78, p < 0.001). CONCLUSION: MEGS showed modest correlation with indices of Crohn's disease activity which corroborates the complementary role of MRE in management of such patients.

Microsatellite instability in young patients with mucinous colorectal cancers - characterization using molecular testing, immunohistochemistry, and histological features.

CONTEXT: The incidence of colorectal cancers (CRCs) in young Indian patients is higher than the international average. CRCs in young patients are commonly of mucinous type and show microsatellite instability (MSI). AIMS: To ascertain the MSI status of mucinous CRCs in patients ≤40 years of age by molecular testing and to correlate this with immunohistochemical (IHC) analysis and tumor histology. SUBJECTS AND METHODS: Archived formalin-fixed paraffin embedded tissue blocks of 30 young mucinous CRC patients were retrieved. MSI testing was done using two mononucleotide markers - BAT26 and NR24. IHC analysis was done using MLH1, MSH2, and MSH6. Histological features of all cases were studied. Data were analyzed using the SPSS software and the Pearson's chi-square test and Fisher's exact test. RESULTS: Eight out of 30 cases (26.7%) showed MSI by molecular testing. IHC identified seven of these cases. Histological features showing a statistically significant association with MSI were the presence of a well-differentiated adenocarcinoma component (P = 0.003), peritumoral lymphocytes (P = 0.002) and tumor budding (P = 0.021). CONCLUSION: The detection of defective mismatch repair (MMR) proteins using IHC for MLH1, MSH2, and MSH6 and molecular testing using BAT26 and NR24 appears to be a good protocol to detect CRCs with MSI. Histology could be useful in identifying cases that require screening for presence of MMR protein defects.

Fibrillary glomerulonephritis in a human immunodeficiency virus-positive, hepatitis C-negative Indian patient: Expanding the profile of renal involvement in human immunodeficiency virus infection.

Highly active anti retroviral therapy (HAART) has dramatically improved life expectancy of human immunodeficiency virus (HIV) infected patients, converting HIV infection into a chronic illness with associated changes in its attendant renal complications. The past two decades have witnessed a decrease in the prevalence of HIV associated nephropathy (HIVAN), traditionally considered to be the hall mark of renal involvement in HIV infection. Simultaneously a host of other glomerular and tubulo-interstitial diseases have emerged, expanding the spectrum of HIV associated renal diseases, predominant among which is HIV associated immune complex mediated kidney diseases (HIVICK). Of the diverse glomerular diseases constituting HIVICK, fibrillary glomerulonephritis (FGN) remains a rarity, with only two existing reports to date, confined to patients co-infected with Hepatitis C virus (HCV). The pathogenetic role of HIV in these patients remains under a cloud because of previously well established association of HCV infection and FGN. We report a case of FGN in a HIV seropositive, HCV negative Indian patient, highlighting the diagnostic electron microscopy (EM) findings of FGN and strengthening the causal association of HIV with FGN. In view of increasing heterogeneity of renal complications in HIV infection, the diagnostic utility of a comprehensive renal biopsy evaluation inclusive of EM is emphasized for appropriate selection of treatment modalities.

Self-directed learning readiness of Indian medical students: a mixed method study.

BACKGROUND: Self-directed learning (SDL) is defined as learning on one's own initiative, with the learner having primary responsibility for planning, implementing, and evaluating the effort. Medical education institutions promote SDL, since physicians need to be self-directed learners to maintain lifelong learning in the ever-changing world of medicine and to obtain essential knowledge for professional growth. The purpose of the study was to measure the self-directed learning readiness of medical students across the training years, to determine the perceptions of students and faculty on factors that promote and deter SDL and to identify the role of culture and curriculum on SDL at the Christian Medical College, Vellore, India. METHODS: Guglielmino's SDL Readiness Scale (SDLRS) was administered in 2015 to six student cohorts (452 students) at admission, end of 1st, 2nd, 3rd and 4th year of training, and at the beginning of internship in the undergraduate medicine (MBBS) program. Analysis of variance (ANOVA) was used to compare SDL scores between years of training. 5 student focus groups and 7 interviews with instructors captured perceptions of self-direction. Transcripts were coded and analyzed thematically. RESULTS: The overall mean SDLRS score was 212.91. There was no significant effect of gender and age on SDLR scores. There was a significant drop in SDLRS scores on comparing students at admission with students at subsequent years of training. Qualitative analysis showed the prominent role of culture and curriculum on SDL readiness. CONCLUSIONS: Given the importance of SDL in medicine, the current curriculum may require an increase in learning activities that promote SDL. Strategies to change the learning environment that facilitates SDL have to be considered.

Spectrum of biopsy proven renal disease in South Asian children: Two decades at a tropical tertiary care centre.

AIM: We report findings from a large single centre paediatric renal biopsy cohort in South Asia. METHODS: We analyzed all renal biopsies performed on children aged ≤18 years between 1996 and 2015 at our centre. The clinical characteristics and histological diagnosis pertaining to each case, distribution of renal diseases in children with various clinical presentations, and changes in the pattern of kidney disease during the study period were analyzed. RESULTS: A total of 1740 paediatric kidney biopsies were performed during the study period. The mean age was 12.8 ± 4.9 years (8 months to 18 years) and the male: female ratio was 1.5:1. The most common indication for renal biopsy was nephrotic syndrome (63.2%) followed by acute nephritic syndrome (13%). Minimal change disease was the most common cause of nephrotic syndrome while endocapillary proliferative glomerulonephritis (65.7% infection related), remained the commonest cause of acute nephritic syndrome. IgA nephropathy was the commonest cause of chronic kidney disease. Contrary to trends in European paediatric cohorts, the frequency of lupus nephritis increased over the two decades of the study, while that of endocapillary proliferative glomerulonephritis did not show any appreciable decline. CONCLUSION: This study provides the largest data on biopsy proven renal disease in children from South Asia published till date and highlights important differences in the spectrum and trends of kidney disease compared to data from other regions.

Investigation into celiac disease in Indian patients with portal hypertension.

BACKGROUND: There is limited data on celiac disease in patients with cryptogenic cirrhosis or idiopathic noncirrhotic intrahepatic portal hypertension (NCIPH). Our objective was to evaluate for celiac disease in patients with portal hypertension in India. METHODS: Consecutive patients with portal hypertension having cryptogenic chronic liver disease (cases) and hepatitis B- or C-related cirrhosis (controls) were prospectively enrolled. We studied tissue transglutaminase (tTG) antibody and duodenal histology in study patients. RESULT: Sixty-one cases (including 14 NCIPH patients) and 59 controls were enrolled. Celiac disease was noted in six cases (including two NCIPH patients) as compared to none in controls. In a significant proportion of the remaining study subjects, duodenal biopsy showed villous atrophy, crypt hyperplasia, and lamina propria inflammation, not accompanied by raised intraepithelial lymphocytes (IELs); this was seen more commonly in cases as compared to controls. An unexpectedly high rate of tTG antibody positivity was seen in study subjects (66 %) of cases as compared to 29 % in controls (p-value < 0.001), which could indicate false-positive test result. CONCLUSION: In this study, 10 % of patients with unexplained portal hypertension (cryptogenic chronic liver disease) had associated celiac disease. In addition, an unexplained enteropathy was seen in a significant proportion of study patients, more so in patients with cryptogenic chronic liver disease. This finding warrants further investigation.

Acute liver injury induced by low dose dimethylnitrosamine alters mediators of hepatic vascular flow.

Alterations in liver vascular tone play an important role in chronic liver disease. The hepatic stellate cell (HSC) and mediators such as nitric oxide (NO) and hydrogen sulfide (H2S) have been implicated in regulation of vascular tone and intra-hepatic pressure. Though these have been studied in chronic liver damage, changes in response to acute liver injury induced by hepatotoxins such as dimethyl nitrosamine are not well understood. Liver injury was induced in mice by a single intra-peritoneal injection of dimethylnitrosamine (DMN), following which animals were sacrificed at 24, 48 and 72 h. Changes in vascular mediators such as NO and H2S as well as stellate cell activation was then examined. It was found that a single low dose of DMN in mice is sufficient to induce activation of hepatic stellate cells within 24 h, accompanied by oxidative stress, compromised metabolism of H2S and decreased levels of the von Willebrand factor (vWF) cleaving protease; a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13), which functions in intravascular thrombosis. A suppression of hepatic NO levels is also initiated at this time point, which progresses further and is sustained up to 72 h, at which point the HSC activation is still present. Compromised levels of ADAMTS13 and H2S metabolism however, begin to recover by 48 h and are almost similar to control by 72 h. In conclusion, these data suggest that even moderate acute insults in the liver can have far reaching consequences on a number of mediators of vascular flow in the liver.

Correlation between coinfection with parasites, cytomegalovirus, and Clostridium difficile and disease severity in patients with ulcerative colitis.

A cross-sectional study was undertaken to determine whether there was any association between intestinal infection (with parasites, cytomegalovirus, or Clostridium difficile) and clinical disease severity in patients with ulcerative colitis (UC). Consecutive cases of UC were enrolled after history and clinical examination, evaluated for presence of stool parasites (routine/special stains) and C. difficile toxins A and B (CDT) in stools. Segmental biopsies at colonoscopy were assessed for cytopathic changes of cytomegalovirus (CMV) infection. Statistical analysis was done to look for associations between the presence of infection and disease severity as assessed by the Truelove-Witts criteria. Eighty-seven patients (males = 51) of mean (SD) age 40.2 (12) years were enrolled. Thirty-nine patients (44.8 %) had severe disease, 11 (12.6 %) had moderate, and 37 (42.6 %) had mild disease. Ten (11.5 %) patients had parasites detected in stool, two (2.3%) had histological evidence of CMV, and three (3.4 %) were positive for CDT. The presence of pathogens was very significantly associated with moderate/severe UC. Thirteen of 15 cases (86 %) with detectable pathogens had moderate or severe UC compared to 37 of 72 cases (51 %) without detectable pathogens (p = 0.0194). The relative risk of a UC patient with stool pathogens having severe disease was 1.686 (95 % CI 1.250 to 2.276) compared to one without stool pathogens. The presence of stool pathogens was associated with disease severity in UC.

Clinical profile and predictors of disease behavior and surgery in Indian patients with Crohn's disease.

BACKGROUND: Recent years have seen the emergence of Crohn's disease (CD) in India and the predictors of disease behavior and surgery in these patients are not known. METHODS: The demographic and clinical profiles of patients diagnosed to have CD from January 1995 to December 2008 were analyzed retrospectively and associations with disease behavior and surgery were determined using multivariate analysis. RESULTS: Two hundred and twenty-three patients (age 35 ± 14.7 years, males 57.9 %) were included. Extraintestinal manifestations were noted in 27.4 % patients. There was a median delay of 24 months to diagnosis; 66 (29.6 %) patients received antitubercular therapy prior to diagnosis. The most common site of involvement was ileocolonic (40.4 %), and the most common disease behavior was nonstricturing and nonpenetrating (57.8 %). The disease was moderate to severe in 79 %. Around 40 % patients had a relapsing course of illness. Seventy-three patients (32.7 %) had at least one surgical intervention. Independent associations with aggressive disease behavior included the presence of small bowel disease and longer duration of illness. Predictors of surgical intervention were male sex, small bowel disease, perianal disease, and aggressive disease behavior. CONCLUSION: Diagnosis of CD is still delayed in India. Longer duration of illness predicted aggressive disease behavior. Surgery was performed more often in males with aggressive disease involving the small bowel and perianal area.

Zinc and zinc related enzymes in precancerous and cancerous tissue in the colon of dimethyl hydrazine treated rats.

Trace element zinc deficiency or excess is implicated in the development or progression of some cancers. The exact role of zinc in the etiology of colon cancer is unclear. To cast light on this question, an experimental model of colon carcinogenesis was applied here. Six week old rats were given sub cutaneous injections of DMH (30 mg/kg body weight) twice a week for three months and sacrificed after 4 months (precancer model) and 6 months (cancer model). Plasma zinc levels showed a significant decrease (p<0.05) at 4 months and a greater significant decrease at 6 months (p<0.01) as compared with controls. In the large intestine there was a significant decrease in tissue zinc levels (p<0.005) and in CuZnSOD, and alkaline phosphatase activity (p<0.05) in the pre-cancerous model and a greater significant decrease in tissue zinc (p<0.0001), and in CuZnSOD and alkaline phosphatase activity (p<0.001), in the carcinoma model. The tissue zinc levels showed a significant decrease in the small intestine and stomach (p<0.005) and in liver (p<0.05) in the cancer model. 87% of the rats in the precancer group and 92% rats in the cancer group showed histological evidence of precancerous lesions and carcinomas respectively in the colon mucosa. This study suggests that the decrease in plasma zinc, tissue zinc and activity of zinc related enzymes are associated with the development of preneoplastic lesions and these biochemical parameters further decrease with progression to carcinoma in the colon.

Activation of phospholipase A2 is involved in indomethacin-induced damage in Caco-2 cells.

Nonsteroidal anti-inflammatory drugs (NSAIDs), widely used in clinical practice, cause adverse effects in the gastrointestinal tract. These effects have been attributed to mechanisms such as drug-induced cyclooxygenase inhibition, oxidative stress, mitochondrial dysfunction and changes in cell membrane lipids. Our previous study showed that indomethacin (an NSAID commonly used in toxicity studies) caused activation of cytosolic phospholipase A(2) (cPLA(2)) in the rat small intestine. We hypothesized that activation of cPLA(2) is an important event in the pathogenesis of indomethacin-induced damage in enterocytes. To test this, we incubated enterocyte-like Caco-2 cells with indomethacin, with and without pretreatment with methyl arachidonyl fluorophosphonate (MAFP), an inhibitor of cPLA(2). Cells treated with indomethacin showed decreased viability and evidence of oxidative stress and morphological cell damage. Phospholipids were degraded in these cells, with increases in the levels of lysophospholipids and arachidonic acid. There was no evidence of apoptosis in the cells in response to the drug. Pretreatment of the cells with MAFP attenuated the drug-induced effects seen. This shows that activation of phospholipase A(2) appears to be an important event in the pathogenesis of indomethacin-induced damage in Caco-2 cells. To our knowledge, this is the first report that implicates the involvement of this enzyme in NSAID-induced enteropathy.

Retinoid metabolism in the small intestine during development of liver cirrhosis.

BACKGROUND AND AIMS: Retinoids are important mediators of cellular differentiation and proliferation in various epithelia of the body including the small intestine. Though alterations in intestinal epithelial cell proliferation have been noted in liver cirrhosis, mechanisms involved in the process are not well understood. This study examined the levels of various retinoids and retinoid-metabolizing enzymes in the small intestine during development of liver cirrhosis. METHODS: Four groups of animals were used (control, phenobarbitone control, thioacetamide and carbon tetrachloride treatment). Twice-weekly intragastric or i.p. administration of carbon tetrachloride or thioacetamide, respectively, produced liver cirrhosis after 3 months, which was confirmed through histology and serum markers. Retinoid levels were measured by high-performance liquid chromatography. RESULTS: A decrease in the levels of retinal, retinoic acid and retinol was evident in the intestine by 3 months, when cirrhosis was evident histologically, and these remained low until 6 months. A decrease in the activities of retinaldehyde oxidase, retinaldehyde reductase and retinol dehydrogenase was also seen in intestine from cirrhotic rats. CONCLUSION: These results suggest that altered retinoid metabolism in the intestine of cirrhotic rats might have an influence on changes in intestinal epithelial cell differentiation, seen in liver cirrhosis.

How reliable an indicator of inflammation is myeloperoxidase activity?

BACKGROUND: Myeloperoxidase (MPO) and interleukin-6 (IL-6) are often used as markers of inflammation. The aim of this study was to ascertain whether MPO activity is as reliable as IL-6 as an indicator of inflammation. METHODS: Inflammation was induced in mice, using either turpentine or indomethacin. Duodenal tissue was removed from these animals at various time periods ranging from 6 h to 7 days later. Concentrations of IL-6 and MPO activity were estimated in the tissue. Histopathological examination was also carried out at some of the time periods to determine the presence of neutrophil infiltration in turpentine-treated mice. RESULTS: Concentrations of IL-6 and MPO activity were significantly higher in tissue that had been treated with the agents used, at all the time periods studied, when compared with corresponding control tissue. Fold-increases in MPO activity were higher than fold-increases in IL-6. Concentrations of the 2 parameters showed significant positive correlation. Histopathological examination did not show significantly higher numbers of neutrophils infiltrating the tissue in response to turpentine, at the time periods studied. CONCLUSIONS: Estimation of MPO activity is a reliable indicator of inflammation, being more sensitive than histopathological examination of tissue and as good as measurement of IL-6 concentrations.

In situ PCR for Mycobacterium tuberculosis in endoscopic mucosal biopsy specimens of intestinal tuberculosis and Crohn disease.

Tuberculosis and Crohn disease are granulomatous disorders affecting the intestinal tract with similar clinical manifestations and pathologic features. We evaluated the use of in situ polymerase chain reaction (PCR) using Mycobacterium tuberculosis complex-specific primers for IS 6110 to differentiate these 2 disorders in archival mucosal biopsy specimens. In situ PCR was positive in 6 of 20 tuberculosis biopsy specimens and 1 of 20 Crohn disease biopsy specimens. Staining was localized to a site of granulomatous inflammation in 3 of the tuberculosis specimens and in the Crohn disease specimen. In the other tuberculosis biopsy specimens, positive staining was localized to inflammatory granulation tissue and to a focus of intact mucosa without granulomatous inflammation. The presence of M tuberculosis DNA in Crohn disease could be due to coexisting latent tuberculosis or indicate a role for these bacteria in triggering an abnormal immune response. Therefore, in situ PCR is potentially useful to differentiate intestinal tuberculosis from Crohn disease, if the sensitivity is improved.

Early activation of mucosal dendritic cells and macrophages in acute Campylobacter colitis and cholera: An in vivo study.

BACKGROUND AND AIM: Macrophages and dendritic cells are closely related mononuclear phagocytic cells. Little is known about their in vivo role in acute intestinal bacterial infections in humans. We undertook to evaluate these cells in rectal mucosal biopsies of patients with acute colitis. METHODS: All mucosal mononuclear phagocytic cells in rectal biopsies of patients with acute Campylobacter colitis (n = 5), shigellosis (n = 5), and cholera (n = 10) were evaluated ultrastructurally and compared with those in controls (n = 5). RESULTS: Mononuclear phagocytic cells in the superficial rectal mucosa showed a higher prevalence of ultrastructural features of activation in Campylobacter colitis and cholera than in controls. A lower prevalence of features of activation with increased monocytes was seen in shigellosis. Cells with the ultrastructural morphology of activated dendritic cells constituted 41% and 45% of all mononuclear phagocytic cells in two of five patients with Campylobacter colitis and 4-22% of cells in four of 10 patients with cholera. Their presence in patients with Campylobacter colitis was associated with significant surface epithelial damage and prominent acute inflammatory changes in the mucosa. CONCLUSIONS: This is the first ultrastructural study to show activated macrophages and dendritic cells in vivo in acute Campylobacter colitis and cholera. Dendritic cell activation occurred early in the clinical course of these infections. Surface epithelial damage may play a role in the activation of dendritic cells.