Anil K Verma

Prevalence of celiac disease in the northern part of India: A community based study

Background and Aim:  While celiac disease is estimated to affect about 1% of the worlds population, it is thought to be uncommon not only in India but in Asia also. There is a lack of studies on the prevalence of celiac disease from Asian nations. The aim of the present study was to estimate the prevalence of celiac disease in the community.

Prevalence of Irritable Bowel Syndrome: A Community Based Study From Northern India

BACKGROUND/AIMS The prevalence of irritable bowel syndrome (IBS) varies from 4% to 20% in different Asian nations. Prevalence of IBS in native North Indian community is not known. METHODS Between November 2008 to December 2009, we estimated the prevalence of IBS in a rural community of Ballabgarh block, located in Haryana state. A structured questionnaire based on Rome III module was used to collect symptoms related to IBS from all the participants in a door to door survey. A Rome III criterion was used for diagnosis of IBS. IBS was further classified based on predominance of symptoms as constipation predominant, diarrhea predominant, mixed and unspecified based on Rome III module. RESULTS There were 4,767 participants (mean age 34.6 ± 10.8, males 50%). Overall, 555 (11.6%; 95% CI, 10.7-12.5) had constipation, 542 (11.4%; 95% CI, 10.5-12.3) diarrhea and 823 (17.3%; 95% CI, 16.2-18.4) abdominal pain. The overall prevalence of IBS was 4% (95% CI, 3.5-4.6). The prevalence of constipation predominant IBS was 0.3% (95% CI, 0.16-0.49), diarrhea predominant IBS 1.5% (95% CI, 1.18-1.90), mixed IBS 1.7% (95% CI, 1.35-2.11) and unsubtyped IBS 0.5% (95% CI, 0.32-0.75). The prevalence of IBS was significantly higher in females compared with males (4.8% vs 3.2%, P = 0.008). However, there was no significant difference between males and females in the prevalence of different subtypes of IBS. The prevalence increased with age. CONCLUSIONS The prevalence of IBS in a North Indian community is 4%. IBS poses a significant burden on the rural adults.

Celiac disease: A disease with varied manifestations in adults and adolescents

We aimed to determine the characteristics of patients with celiac disease and differences between those who presented during adolescence or adulthood.

CYP3A4-Catalyzed Simvastatin Metabolism as a Non-Invasive Marker of Small Intestinal Health in Celiac Disease

OBJECTIVES:Histological examination of duodenal biopsies is the gold standard for assessing intestinal damage in celiac disease (CD). A noninvasive marker of disease status is necessary, because obtaining duodenal biopsies is invasive and not suitable for routine monitoring of CD patients. As the small intestine is a major site of cytochrome P450 3A4 (CYP3A4) activity and also the location of the celiac lesion, we investigated whether patients with active CD display abnormal pharmacokinetics of an orally administered CYP3A4 substrate, simvastatin (SV), which could potentially be used for noninvasive assessment of their small intestinal health.METHODS:Preclinical experiments were performed in CYP3A4-humanized mice to examine the feasibility of the test. Subsequently, a clinical trial was undertaken with 11 healthy volunteers, 18 newly diagnosed patients with CD, and 25 celiac patients who had followed a gluten-free diet (GFD) for more than 1 year. The maximum concentration (Cmax) of orally administered SV plus its major non-CYP3A4-derived metabolite SV acid (SV equivalent (SVeq)) was measured, and compared with clinical, histological, and serological parameters.RESULTS:In CYP3A4-humanized mice, a marked decrease in SV metabolism was observed in response to enteropathy. In the clinical setting, untreated celiac patients displayed a significantly higher SVeq Cmax (46±24 nM) compared with treated patients (21±16 nM, P<0.001) or healthy subjects (19±11 nM, P<0.005). SVeq Cmax correctly predicted the diagnosis in 16/18 untreated celiac patients, and also the recovery status of all follow-up patients that exhibited normal or near-normal biopsies (Marsh 0-2). All patients with abnormal SVeq Cmax showed a reduction in the value after 1 year of following a GFD.CONCLUSIONS:SVeq Cmax is a promising noninvasive marker for assessment of small intestinal health. Further studies are warranted to establish its clinical utility for assessing gut status of patients with CD.

Titers of anti-tissue transglutaminase antibody correlate well with severity of villous abnormalities in celiac disease.

Goals: We reviewed our celiac disease (CeD) database to study if anti-tissue transglutaminase (tTG) antibody (ab) titers correlate with severity of villous abnormalities in Indian patients and to find out a cutoff value of anti-tTG ab fold-rise, which could best predict CeD. Background: Guidelines for diagnosing CeD suggest that biopsy could be avoided in some patients with high anti-tTG ab titer. Study: We reviewed a cohort of 366 anti-tTG ab–positive individuals in whom duodenal biopsies were performed. Anti-tTG ab was obtained before initiation of gluten-free diet. Anti-tTG ab results were expressed in terms of fold-rise by calculating ratio of observed values with cutoff value. CeD was diagnosed if in addition to positive serology, patients had villous atrophy (>Marsh grade 2) and unequivocal response to gluten-free diet. Results: The mean anti-tTG fold-rise in groups with Marsh grade ⩽2 was 2.6 (±2.5), grade 3a was 4.0 (±3.9), 3b was 5.7 (±5.1), and 3c was 11.8 (±8.0). The positive likelihood ratio for diagnosing CeD was 15.4 and 27.4 at 12- and 14-fold-rise of anti-tTG ab titer, respectively. The positive predictive value of diagnosis of CeD was 100% when anti-tTG ab titer was 14-fold higher over the cutoff value. Fifty-seven (43.9%) individuals with anti-tTG titer rise <2-fold high also had CeD. Conclusions: As severity of villous abnormality increases, titer of anti-tTG also rises. Presence of villous atrophy can be predicted at very high anti-tTG ab titer. In contrast to emerging belief, mucosal biopsies should be performed even if anti-tTG ab titer is <2 times, because many patients with CeD have low titers.

Characterization of Human CD8 T Cell Responses in Dengue Virus-Infected Patients from India

ABSTRACT Epidemiological studies suggest that India has the largest number of dengue virus infection cases worldwide. However, there is minimal information about the immunological responses in these patients. CD8 T cells are important in dengue, because they have been implicated in both protection and immunopathology. Here, we provide a detailed analysis of HLA-DR+ CD38+ and HLA-DR− CD38+ effector CD8 T cell subsets in dengue patients from India and Thailand. Both CD8 T cell subsets expanded and expressed markers indicative of antigen-driven proliferation, tissue homing, and cytotoxic effector functions, with the HLA-DR+ CD38+ subset being the most striking in these effector qualities. The breadth of the dengue-specific CD8 T cell response was diverse, with NS3-specific cells being the most dominant. Interestingly, only a small fraction of these activated effector CD8 T cells produced gamma interferon (IFN-γ) when stimulated with dengue virus peptide pools. Transcriptomics revealed downregulation of key molecules involved in T cell receptor (TCR) signaling. Consistent with this, the majority of these CD8 T cells remained IFN-γ unresponsive even after TCR-dependent polyclonal stimulation (anti-CD3 plus anti-CD28) but produced IFN-γ by TCR-independent polyclonal stimulation (phorbol 12-myristate 13-acetate [PMA] plus ionomycin). Thus, the vast majority of these proliferating, highly differentiated effector CD8 T cells probably acquire TCR refractoriness at the time the patient is experiencing febrile illness that leads to IFN-γ unresponsiveness. Our studies open novel avenues for understanding the mechanisms that fine-tune the balance between CD8 T cell-mediated protective versus pathological effects in dengue. IMPORTANCE Dengue is becoming a global public health concern. Although CD8 T cells have been implicated both in protection and in the cytokine-mediated immunopathology of dengue, how the balance is maintained between these opposing functions remains unknown. We comprehensively characterized CD8 T cell subsets in dengue patients from India and Thailand and show that these cells expand massively and express phenotypes indicative of overwhelming antigenic stimulus and tissue homing/cytotoxic-effector functions but that a vast majority of them fail to produce IFN-γ in vitro. Interestingly, the cells were fully capable of producing the cytokine when stimulated in a T cell receptor (TCR)-independent manner but failed to do so in TCR-dependent stimulation. These results, together with transcriptomics, revealed that the vast majority of these CD8 T cells from dengue patients become cytokine unresponsive due to TCR signaling insufficiencies. These observations open novel avenues for understanding the mechanisms that fine-tune the balance between CD8-mediated protective versus pathological effects.

Prevalence of celiac disease in Indian patients with irritable bowel syndrome and uninvestigated dyspepsia.

The clinical spectrum of celiac disease (CeD) is wide and its symptoms overlap with those of functional bowel diseases. This study aimed to investigate the relationship among gluten‐related disorders, irritable bowel syndrome (IBS) and uninvestigated dyspepsia in Indian patients.

High yield expression and purification of Chikungunya virus E2 recombinant protein and its evaluation for serodiagnosis

Disease caused by Chikungunya virus (CHIKV) is clinically characterized by sudden-onset of fever and severe arthralgia, which may persist for weeks, months, or years after acute phase of the infection. CHIKV is spreading globally; in India it first appeared in the 1960s followed by a quiescent period and then a full-blown remergence in 2006 and sporadic persistence since then. Despite a large number of commercially available diagnostic kits for CHIKV, clinical preparedness and diagnostics suffer from sub-optimal assays. An international diagnostic laboratory survey suggested that there is a critical need for improved CHIKV diagnostics especially in the early acute phase of illness. With the recent studies indicating that a vast majority of human humoral response in CHIKV infection is directed against E2 protein, this supports strong interest to develop CHIKV E2 based serological tests. However, methods to produce large amounts of CHIKV protein are limited. Here we report cloning, expression and purification methods for obtaining a truncated 37kDa Chikungunya E2 protein at a high yield of 65-70mg/l. We found that this purified protein can be reliably used in ELISA and western blot to detect CHIKV specific antibodies in sera from patients who were PCR or IgM positive. Thus, using this protocol, laboratories can make large quantities of purified protein that can be potentially used in CHIKV serological analysis.

Patients with mild enteropathy have apoptotic injury of enterocytes similar to that in advanced enteropathy in celiac disease

BACKGROUND Severity of villous atrophy in celiac disease (CeD) is the cumulative effect of enterocyte loss and cell regeneration. Gluten-free diet has been shown to benefit even in patients having a positive anti-tissue transglutaminase (tTG) antibody titre and mild enteropathy. AIM We explored the balance between mucosal apoptotic enterocyte loss and cell regeneration in mild and advanced enteropathies. METHODS Duodenal biopsies from patients with mild enteropathy (Marsh grade 0 and 1) (n=26), advanced enteropathy (Marsh grade ≥2) (n=41) and control biopsies (n=12) were subjected to immunohistochemical staining for end-apoptotic markers (M30, H2AX); markers of cell death (perforin, annexin V); and cell proliferation (Ki67). Composite H-scores based on the intensity and distribution of markers were compared. RESULTS End-apoptotic markers and marker of cell death (perforin) were significantly up-regulated in both mild and advanced enteropathies, in comparison to controls; without any difference between mild and advanced enteropathies. Ki67 labelling index was significantly higher in crypts of mild enteropathy, in comparison to controls, suggesting maintained regenerative activity in the former. CONCLUSIONS Even in patients with mild enteropathy, the rate of apoptosis is similar to those with advanced enteropathy. These findings suggest the necessity of reviewing the existing practice of not treating patients with mild enteropathy.

Comparison of Small Gut and Whole Gut Microbiota of First-Degree Relatives with Adult Celiac Disease Patients and Controls

Objectives Gut microbiota gets altered in patients with celiac disease (CeD) and whether these microbiota changes are the cause or effect of the disease is not well understood to date. The first degree relatives (FDRs) of CeD patients are genetically susceptible and may represent a pre-diseased state. Therefore, understanding differences in duodenal and faecal microbiota composition between the FDR and CeD subjects is of interest. To investigate this, we characterised the microbiota in duodenal biopsies and faeces of CeD patients (n = 23), FDRs (n = 15) and control subjects (DC, n= 24) by 16S rRNA gene sequencing. Results Duodenal biopsies showed more diverse pattern in microbial community composition and structure than faecal samples. In duodenal biopsies, 52 OTUs and 41 OTUs were differentially abundant between the FDR and DC group, and between the FDR and CeD group respectively (p < 0.01). In faecal samples, 30 OTUs were differentially abundant between FDR and DC, and 81 between FDR and CeD (p < 0.01). Predicted metagenomes from duodenal microbiomes of FDR and CeD showed a lower genetic potential for metabolizing gluten as compared to controls. Conclusions The microbial communities of FDR and CeD groups are more similar to each other than to the control groups. Significant differences at OTU level suggest that specific bacterial taxa may be important for pathogenesis of CeD. Moreover, the predicted differences in gluten metabolism potential by the FDR and CeD microbiota point towards the need for investigating functional capabilities of specific bacterial taxa in healthy FDR and CeD patients.