Onset of coeliac disease during treatment with interferon for chronic hepatitis C

Seroprevalence of Anti-tTg-IgA among Symptomized Celiac Disease Patients and Their Correlation with Rotavirus Infection

Celiac disease (CD) is a chronic inflammatory disorder in the intestinal tract as a response to the use of gluten in genetically predisposed individuals. It is a worldwide problem, with a high prevalence rate in North America. This is a descriptive cross-sectional study involving 1090 samples collected from different hospitals of Rawalpindi and Islamabad, Pakistan, from January 2019 to December 2019. In this study, 1090 blood samples screened for seroprevalence of anti-tTG antibodies in CD symptomatic patients via ELISA (enzyme-linked immunosorbent assay). 1090 fecal samples from the same CD patients were collected and tested for the presence of rotavirus (RV) via ELISA and RT-PCR. Of the 1090 patients tested for seroprevalence of anti-tTG antibodies, 112/1090 (10.3%) were found to be positive. Of the 112 anti-tTG-positive patients, 78/112 (70%) were positive for RV via ELISA and 74/112 (66.1%) were RV positive via RT-PCR. A statistically significant association was reported between rotavirus infection and celiac disease (p˂0.05). Anti-tTG antibodies were higher in age group 6 (12-18 years) patients (18.4%) and at minimum in age group 3 (1-3 years) patients (4.8%). However, there was a statistically insignificant relationship between group age and CD prevalence (p > 0.05). The highest CD prevalence was noted during winter season (19.6%) and the lowest (3.0%) during fall/autumn. Our study findings demonstrate that Pakistan has a high prevalence of CD compared to other studies. Further studies in the fields of environmental risk factors and treatment with more advanced serological and histopathological studies are needed in the future.

Therapeutic agents affecting the immune system and drug-induced inflammatory bowel disease (IBD): A review on etiological and pathogenetic aspects

In recent years, therapeutic agents affecting the immune system have been largely implemented in the treatment of various hematological, rheumatological and dermatological disorders. Their clinical use has offered important benefits for affected patients and has also ameliorated clinical outcome and prognosis in many cases. Nonetheless, as any treatment, the use of these drugs may be associated with side effects. One of the target organs in such cases is the gastrointestinal tract. In particular, the exacerbation or the onset of inflammatory bowel disease (IBD) in treated patients is not infrequent, although the mechanism of action of these agents may be different. In this review we will focus on the use of therapeutic agents affecting the immune system and the development or exacerbation of IBD, with a mention on the possible underlying pathogenetic mechanisms.

Immune checkpoint inhibitor-associated celiac disease

BACKGROUND

Rare cases of immune checkpoint inhibitor (ICI)-associated celiac disease (ICI-CeD) have been reported, suggesting that disruption of tolerance mechanisms by ICIs can unmask celiac disease (CeD). This study aims to characterize the clinicopathological and immunophenotypic features of ICI-CeD in comparison to ICI-associated duodenitis (ICI-Duo) and usual CeD.

METHODS

A medical and pathological records search between 2015 and 2019 identified eight cases of ICI-CeD, confirmed by tTG-IgA. Nine cases of ICI-Duo, 28 cases of moderate CeD, as well as 5 normal controls were used as comparison groups. Clinical information was collected from the electronic medical records. Immunohistochemistry for CD3, CD8, T-cell receptor gamma/delta (γδ), programmed death ligand 1 (PD-L1), and programmed death 1 (PD-1) were performed, with quantification of intraepithelial lymphocyte (IEL) subsets in three well-oriented villi. CD68, PD-L1, and PD-1 were assessed as a percentage of lamina propria surface area infiltrated by positive cells. Statistical significance was calculated by the Student's t-test and Fisher's exact test.

RESULTS

The eight patients with ICI-CeD (F:M=1:3) and nine patients with ICI-Duo (F:M=5:4) presented similarly with diarrhea (13/17) and abdominal pain (11/17) after a median of 1.6 months on ICI therapy. In patients with ICI-CeD, tTG-IgA ranged from 104 to >300 IU/mL. Histological findings in ICI-CeD and ICI-Duo were similar and included expansion of the lamina propria, active neutrophilic duodenitis, variably increased IELs, and villous blunting. Immunohistochemistry showed that the average number of IELs per 100 enterocytes is comparable between ICI-CeD and ICI-Duo, with increased CD3⁺ CD8⁺ T cells compared with normal duodenum but decreased γδ T cells compared with CeD. Average PD-L1 percentage was 9% in ICI-CeD and 18% in ICI-Duo, in comparison to <1% in CeD and normal duodenum; average PD-1 percentage was very low to absent in all cases (<3%). On follow-up, five patients with ICI-CeD improved on a gluten-free diet (GFD) as the sole therapeutic intervention (with down-trending tTG-IgA) while the other three required immunosuppression. All patients who developed ICI-Duo received immunosuppression with variable improvement in symptoms.

CONCLUSIONS

ICI-CeD resembles ICI-Duo clinically and histologically but shares the serological features and response to gluten withdrawal with classic CeD. Immunophenotyping of IELs in ICI-CeD and ICI-Duo also shows similar CD3, CD8, γδ T cell subsets, and PD-L1 populations, all of which differed quantitatively from usual CeD. We conclude that ICI-CeD is biologically similar to ICI-Duo and is likely a variant of ICI-Duo, but treatment strategies differ, with ICI-CeD often improving with GFD alone, whereas ICI-Duo requires systemic immunosuppression.

Small and Large Intestine (I): Malabsorption of Nutrients

Numerous disorders can alter the physiological mechanisms that guarantee proper digestion and absorption of nutrients (macro- and micronutrients), leading to a wide variety of symptoms and nutritional consequences. Malabsorption can be caused by many diseases of the small intestine, as well as by diseases of the pancreas, liver, biliary tract, and stomach. This article provides an overview of pathophysiologic mechanisms that lead to symptoms or complications of maldigestion (defined as the defective intraluminal hydrolysis of nutrients) or malabsorption (defined as defective mucosal absorption), as well as its clinical consequences, including both gastrointestinal symptoms and extraintestinal manifestations and/or laboratory abnormalities. The normal uptake of nutrients, vitamins, and minerals by the gastrointestinal tract (GI) requires several steps, each of which can be compromised in disease. This article will first describe the mechanisms that lead to poor assimilation of nutrients, and secondly discuss the symptoms and nutritional consequences of each specific disorder. The clinician must be aware that many malabsorptive disorders are manifested by subtle disorders, even without gastrointestinal symptoms (for example, anemia, osteoporosis, or infertility in celiac disease), so the index of suspicion must be high to recognize the underlying diseases in time.

Immune-mediated enteropathies: From bench to bedside

Immune-mediated enteropathies are caused by excessive reactions of the intestinal immune system towards non-pathogenic molecules. Enteropathy leads to malabsorption-related symptoms and include (severe) chronic diarrhea, weight loss and vitamin deficiencies. Parenteral feeding and immunosuppressive therapy are needed in severe cases. Celiac disease has long been recognized as the most common immune-mediated enteropathy in adults, but the spectrum of immune-mediated enteropathies has been expanding. Histological and clinical features are sometimes shared among these enteropathies, and therefore it may be challenging to differentiate between them. Here, we provide an overview of immune-mediated enteropathies focused on clinical presentation, establishing diagnosis, immunopathogenesis, and treatment options.

Cellular and molecular bases of refractory celiac disease

Refractory celiac disease (RCD) encompasses biologically heterogeneous disorders that develop in a small proportion (0.3%) of individuals with celiac disease that are associated with high morbidity. Two broad categories are currently recognized, type I (RCD I) and type II (RCD II), based on immunophenotypic and molecular features of the intraepithelial lymphocytes (IELs). RCD I is characterized by a polyclonal expansion of IELs displaying a normal immunophenotype, while RCD II represents a clonal proliferation of immunophenotypically "aberrant" IELs, and is considered a low-grade lymphoproliferative disorder. The pathogenesis of RCD I has not been clarified, but limited studies suggest multifactorial etiology. On the other hand, recent immunologic, molecular and immunophenotypic analyses have proposed lineage-negative innate IELs to be the cell of origin of a proportion of RCD II cases. Furthermore, sequencing studies have identified frequent, recurrent, activating mutations in members of the JAK-STAT pathway in RCD II. This finding, in conjunction with prior in vitro experimental observations, suggests roles of deregulated cytokine signaling in disease pathogenesis. In this review, we describe current understanding of environmental, immune and genetic factors associated with the development of RCD and briefly discuss diagnostic and therapeutic considerations.

The Intestinal Virome and Immunity

The composition of the human microbiome is considered a major source of interindividual variation in immunity and, by extension, susceptibility to diseases. Intestinal bacteria have been the major focus of research. However, diverse communities of viruses that infect microbes and the animal host cohabitate the gastrointestinal tract and collectively constitute the gut virome. Although viruses are typically investigated as pathogens, recent studies highlight a relationship between the host and animal viruses in the gut that is more akin to host-microbiome interactions and includes both beneficial and detrimental outcomes for the host. These viruses are likely sources of immune variation, both locally and extraintestinally. In this review, we describe the components of the gut virome, in particular mammalian viruses, and their ability to modulate host responses during homeostasis and disease.

Interferon alpha: The key trigger of type 1 diabetes

IFNα is a cytokine essential to a vast array of immunologic processes. Its induction early in the innate immune response provides a priming mechanism that orchestrates numerous subsequent pathways in innate and adaptive immunity. Despite its beneficial effects in viral infections IFNα has been reported to be associated with several autoimmune diseases including autoimmune thyroid disease, systemic lupus erythematosus, rheumatoid arthritis, primary biliary cholangitis, and recently emerged as a major cytokine that triggers Type 1 Diabetes. In this review, we dissect the role of IFNα in T1D, focusing on the potential pathophysiological mechanisms involved. Evidence from human and mouse studies indicates that IFNα plays a key role in enhancing islet expression of HLA-I in patients with T1D, thereby increasing autoantigen presentation and beta cell activation of autoreactive cytotoxic CD8 T-lymphocytes. The binding of IFNα to its receptor induces the secretion of chemokines, attracting monocytes, T lymphocytes, and NK cells to the infected tissue triggering autoimmunity in susceptible individuals. Furthermore, IFNα impairs insulin production through the induction of endoplasmic reticulum stress as well as by impairing mitochondrial function. Due to its central role in the early phases of beta cell death, targeting IFNα and its pathways in genetically predisposed individuals may represent a potential novel therapeutic strategy in the very early stages of T1D.

Prevalence of celiac disease in adult Chinese patients with diarrhea-predominant irritable bowel syndrome: A prospective, controlled, cohort study

OBJECTIVE

Celiac disease is a chronic inflammatory enteropathy with a symptom spectrum similar to that of irritable bowel syndrome (IBS). It is a common but largely undiagnosed condition in the Western countries. However, it is extremely rare among Chinese individuals, and few studies have investigated its prevalence in China. The aim was to determine the prevalence of celiac disease in patients with IBS who were diagnosed using the Rome III criteria in a single center of northern China.

METHODS

This was a single-center, prospective, controlled cohort study performed in Qilu Hospital involving 246 patients with IBS and 246 healthy controls. Blood samples were drawn to assess serum tissue transglutaminase immunoglobulin A (tTg-IgA). Patients with a positive or equivocal tTg-IgA (≥15 U/mL) were subjected to probe-based confocal laser endomicroscopy (pCLE) and duodenal biopsy to confirm celiac disease.

RESULTS

Altogether 12 (4.9%) patients with IBS and two (0.8%) healthy controls were positive or equivocal for serum tTg-IgA. Of these, five patients with IBS underwent pCLE and a targeted biopsy; all were histopathologically found to have celiac disease, although one was eventually diagnosed with lymphoma. After implementation of a gluten-free diet, seven patients serologically positive for IBS showed clinical improvement, thus our study illustrated a minimum prevalence of 2.85% of celiac disease among patients with IBS in our center.

CONCLUSIONS

Celiac disease is not rare in Chinese individuals, particularly among those with IBS. Therefore, it should receive higher attention in clinical practice in China.

The human digestive tract has proteases capable of gluten hydrolysis

OBJECTIVE

To identify, purify, and characterize the proteins responsible for glutenase activity in the feces of healthy subjects and patients with celiac disease (CD).

METHODS

Sixteen subjects were included in this study; 8 were healthy with no known food intolerances, and 8 were treated CD patients on a gluten-free diet. Fecal samples were homogenized, and precipitated proteins were purified by chromatography. Glutenase activity was evaluated by bioassays, zymography, and high-performance liquid chromatography with immunogenic 33-mer, 19-mer, and 13-mer gliadin peptides.

RESULTS

The gastrointestinal elastase 3B (CEL3B), elastase 2A (CEL2A), and carboxypeptidase A1 (CBPA1) enzymes degraded human gluten. These proteins fully hydrolyzed 13-mer and 19-mer gliadin peptides that trigger immune-mediated enteropathy in individuals genetically predisposed to CD and partially digested a 33-mer. Feces from patients with CD showed more glutenase activity than feces from individuals without CD (171-466% higher). Peptidase activity against the gliadin peptides also increased in patients with CD.

CONCLUSION

The digestive tracts of patients with CD and healthy subjects have enzymatic machinery needed for gluten degradation. Patients with CD showed more gluten hydrolysis than did healthy individuals, although, in both cases, a fraction of 33-mer peptide remained intact. Gliadin peptides derived from gastrointestinal digestion, especially the 33-mer, can potentially be used by commensal microbiota from both CD-positive and CD-negative individuals, and differences in bacterial hydrolysis can modify its immunogenic capacity.

Type I and III Interferon in the Gut: Tight Balance between Host Protection and Immunopathology

The intestinal mucosa forms an active interface to the outside word, facilitating nutrient and water uptake and at the same time acts as a barrier toward the highly colonized intestinal lumen. A tight balance of the mucosal immune system is essential to tolerate harmless antigens derived from food or commensals and to effectively defend against potentially dangerous pathogens. Interferons (IFN) provide a first line of host defense when cells detect an invading organism. Whereas type I IFN were discovered almost 60 years ago, type III IFN were only identified in the early 2000s. It was initially thought that type I IFN and type III IFN performed largely redundant functions. However, it is becoming increasingly clear that type III IFN exert distinct and non-redundant functions compared to type I IFN, especially in mucosal tissues. Here, we review recent progress made in unraveling the role of type I/III IFN in intestinal mucosal tissue in the steady state, in response to mucosal pathogens and during inflammation.

To screen or not to screen? Celiac antibodies in liver diseases

Celiac disease (CD) is a systemic immune-mediated disorder triggered by dietary gluten in genetically predisposed individuals. The typical symptoms are anemia, diarrhea, fatigue, weight loss, and abdominal pain. CD has been reported in patients with primary sclerosing cholangitis, primary biliary cholangitis, autoimmune hepatitis, aminotransferase elevations, nonalcoholic fatty liver disease, hepatitis B, hepatitis C, portal hypertension and liver cirrhosis. We evaluate recommendations for active screening for CD in patients with liver diseases, and the effect of a gluten-free diet in these different settings. Active screening for CD is recommended in patients with liver diseases, particularly in those with autoimmune disorders, steatosis in the absence of metabolic syndrome, noncirrhotic intrahepatic portal hypertension, cryptogenic cirrhosis, and in the context of liver transplantation. In hepatitis C, diagnosis of CD can be important as a relative contraindication to interferon use. Gluten-free diet ameliorates the symptoms associated with CD; however, the associated liver disease may improve, remain the same, or progress.

The progression of coeliac disease: its neurological and psychiatric implications

The aim of the paper is to show the various neurological and psychiatric symptoms in coeliac disease (CD). CD is a T cell-mediated, tissue-specific autoimmune disease which affects genetically susceptible individuals after dietary exposure to proline- and glutamine-rich proteins contained in certain cereal grains. Genetics, environmental factors and different immune systems, together with the presence of auto-antigens, are taken into account when identifying the pathogenesis of CD. CD pathogenesis is related to immune dysregulation, which involves the gastrointestinal system, and the extra-intestinal systems such as the nervous system, whose neurological symptoms are evidenced in CD patients. A gluten-free diet (GFD) could avoid cerebellar ataxia, epilepsy, neuropathies, migraine and mild cognitive impairment. Furthermore, untreated CD patients have more symptoms and psychiatric co-morbidities than those treated with a GFD. Common psychiatric symptoms in untreated CD adult patients include depression, apathy, anxiety, and irritability and schizophrenia is also common in untreated CD. Several studies show improvement in psychiatric symptoms after the start of a GFD. The present review discusses the state of the art regarding neurological and psychiatric complications in CD and highlights the evidence supporting a role for GFD in reducing neurological and psychiatric complications.

Innate immunity: actuating the gears of celiac disease pathogenesis

Celiac disease is a T cell mediated immune disorder characterized by the loss of oral tolerance to dietary gluten and the licensing of intraepithelial lymphocytes to kill intestinal epithelial cells, leading to villous atrophy. Innate immunity plays a critical role in both of these processes and cytokines such as interleukin-15 and interferon-α can modulate innate processes such as polarization of dendritic cells as well as intraepithelial lymphocyte function. These cytokines can be modulated by host microbiota, which can also influence dendritic cell function and intraepithelial lymphocyte homeostasis. We will elaborate on the role of interleukin-15, interferon-α, and the microbiota in modulating the processes that lead to loss of tolerance to gluten and tissue destruction in celiac disease.

Autoantibodies in chronic hepatitis C: A clinical perspective

Non-organ-specific autoantibodies and thyroid autoantibodies have been frequently found in chronic carriers of hepatitis C virus (HCV). With respect to endomysial antibodies and tissue transglutaminase, it is controversial whether the prevalence of gluten-related seromarkers is higher in patients with HCV. In such cases, in addition to acknowledging any currently existing autoimmune disease, recognizing the risk of the patient developing an autoimmune disease during interferon (IFN)-based treatment must be a principle concern. From a clinical point-of-view, the presence of autoantibodies arouses suspicion that an autoimmune disease may be present or may be precipitated by IFN-based HCV treatment. In this paper, we review the prevalence of autoantibodies in individuals with hepatitis C, the clinical significance of these autoantibodies, and the approach recommended for such situations.

IL-15: a central regulator of celiac disease immunopathology

Interleukin-15 (IL-15) exerts many biological functions essential for the maintenance and function of multiple cell types. Although its expression is tightly regulated, IL-15 upregulation has been reported in many organ-specific autoimmune disorders. In celiac disease, an intestinal inflammatory disorder driven by gluten exposure, the upregulation of IL-15 expression in the intestinal mucosa has become a hallmark of the disease. Interestingly, because it is overexpressed both in the gut epithelium and in the lamina propria, IL-15 acts on distinct cell types and impacts distinct immune components and pathways to disrupt intestinal immune homeostasis. In this article, we review our current knowledge of the multifaceted roles of IL-15 with regard to the main immunological processes involved in the pathogenesis of celiac disease.

New-onset of celiac disease during interferon-based therapy for hepatitis C

We present the case of a patient who first developed symptoms of celiac disease while on interferon-based therapy for treatment of chronic hepatitis C. He required hospital admission for symptom management and diagnostic work-up of severe diarrhoea. He made a rapid recovery with a gluten-free diet and was able to continue therapy. Consideration should be given to screening for celiac disease prior to the commencement of interferon-based therapy, particularly in high-prevalence populations.

Pathologic bone alterations in celiac disease: etiology, epidemiology, and treatment

Low bone mineral density (BMD), osteopenia, and osteoporosis are frequent complications of celiac disease (CD). The etiology of pathologic bone alterations in CD is multifactorial; however, two main mechanisms are involved: intestinal malabsorption and chronic inflammation. A strict gluten-free diet (GFD) is thought to be the only effective treatment for CD; but treating bone complications related to CD remains complex. The objective of this review is to elucidate the bones problems related to CD and to increase awareness of osteoporosis development, considered as a sign of atypical CD presentation. Currently, a question of whether GFD alone is an effective treatment to correct the bone alterations in patients with CD is under debate. This review presents factors contributing to pathologic bone derangement, recent research on the epidemiology of low BMD, osteoporosis, and fractures, and the treatment of bone problems in patients with CD. The roles of calcium and transport mechanisms are additionally presented.

IL-15: a central regulator of celiac disease immunopathology

Interleukin-15 (IL-15) exerts many biological functions essential for the maintenance and function of multiple cell types. Although its expression is tightly regulated, IL-15 upregulation has been reported in many organ-specific autoimmune disorders. In celiac disease, an intestinal inflammatory disorder driven by gluten exposure, the upregulation of IL-15 expression in the intestinal mucosa has become a hallmark of the disease. Interestingly, because it is overexpressed both in the gut epithelium and in the lamina propria, IL-15 acts on distinct cell types and impacts distinct immune components and pathways to disrupt intestinal immune homeostasis. In this article, we review our current knowledge of the multifaceted roles of IL-15 with regard to the main immunological processes involved in the pathogenesis of celiac disease.

Intestinal stem cells and celiac disease

Stem cells (SCs) are the key to tissue genesis and regeneration. Given their central role in homeostasis, dysfunctions of the SC compartment play a pivotal role in the development of cancers, degenerative disorders, chronic inflammatory pathologies and organ failure. The gastrointestinal tract is constantly exposed to harsh mechanical and chemical conditions and most of the epithelial cells are replaced every 3 to 5 d. According to the so-called Unitarian hypothesis, this renewal is driven by a common intestinal stem cell (ISC) residing within the crypt base at the origin of the crypt-to-villus hierarchical migratory pattern. Celiac disease (CD) can be defined as a chronic immune-mediated disease that is triggered and maintained by dietary proteins (gluten) in genetically predisposed individuals. Many advances have been achieved over the last years in understanding of the pathogenic interactions among genetic, immunological and environmental factors in CD, with a particular emphasis on intestinal barrier and gut microbiota. Conversely, little is known about ISC modulation and deregulation in active celiac disease and upon a gluten-free diet. Nonetheless, bone marrow-derived SC transplantation has become an option for celiac patients with complicated or refractory disease. This manuscript summarizes the “state of the art” regarding CD and ISCs, their niche and potential role in the development and treatment of the disease.

The role of celiac disease in severity of liver disorders and effect of a gluten free diet on diseases improvement

CONTEXT

Celiac disease (CD) is defined as a permanent intolerance to ingested gluten. The intolerance to gluten results in immune-mediated damage of small intestine mucosa manifested by villous atrophy and crypt hyperplasia. These abnormalities resolve with initiationa gluten-free diet.

EVIDENCE ACQUISITION

PubMed, Ovid, and Google were searched for full text articles published between 1963 and 2012. The associated keywords were used, and papers described particularly the impact of celiac disease on severity of liver disorder were identified.

RESULTS

Recently evidence has emerged revealingthat celiac disease not only is associated with small intestine abnormalities and malabsorption, but is also a multisystem disorder affecting other systems outside gastrointestinal tract, including musculo-skeletal, cardiovascular and nervous systems. Some correlations have been assumed between celiac and liver diseases. In particular, celiac disease is associated with changes in liver biochemistry and linked to alter the prognosis of other disorders. This review will concentrate on the effect of celiac disease and gluten-free diets on the severity of liver disorders.

CONCLUSIONS

Although GFD effect on the progression of CD associated liver diseases is not well defined, it seems that GFD improves liver function tests in patients with a hypertransaminasemia.

Plasmacytoid dendritic cells are scarcely represented in the human gut mucosa and are not recruited to the celiac lesion

Celiac disease (CD) is a chronic small intestinal inflammation precipitated by gluten ingestion. According to case reports, interferon (IFN)-α administration may induce development of overt CD. Plasmacytoid dendritic cells (PDCs) were thought to be the source of IFN-α and promote a T helper type 1 response leading to lesion formation. Surprisingly and contradicting to earlier findings, PDCs were described as the main antigen-presenting cells (APCs) in human duodenal mucosa and particularly in CD. Here we show that when assessed by flow cytometry and in situ staining, PDCs represent < 1% of APCs in both normal duodenal mucosa and the celiac lesion. Low levels of IFN-α were detected in the celiac lesion assessed by western blot, reverse transcriptase (RT)-PCR, and immunohistochemistry. In four cell populations sorted from the celiac lesion (based on their expression of HLA-DR and CD45), we found that equally low levels of mRNA for IFN-α were distributed among these cell populations. Together, these results suggest that relatively small amount of IFN-α, produced by a variety of cell types, is present in the celiac mucosa. IFN-λ, a type III IFN important in intestinal antiviral defense, was produced mainly by APCs, but its expression was not increased in the celiac lesion.

Prevalence and causes of abnormal liver function in patients with coeliac disease

BACKGROUND & AIMS

Coeliac disease patients frequently display mild elevation of liver enzymes and this abnormality usually normalizes after gluten-free diet. To investigate the cause and prevalence of altered liver function tests in coeliac patients, basally and after 1 year of gluten-free diet.

PATIENTS AND METHODS

Data from 245 untreated CD patients (196 women and 49 men, age range 15-80 years) were retrospectively analysed and the liver function tests before and after diet, as well as associated liver pathologies, were assessed.

RESULTS

Overall, 43/245 (17.5%) patients had elevated values of one or both aminotransferases; the elevation was mild (<5 times the upper reference limit) in 41 (95%) and marked (>10 times the upper reference limit) in the remaining 2 (5%) patients. After 1 year of gluten-free diet, aminotransferase levels normalized in all but four patients with HCV infection or primary biliary cirrhosis.

CONCLUSIONS

In coeliac patients, hypertransaminaseaemia at diagnosis and the lack of normalization of liver enzymes after 12 months of diet suggest coexisting liver disease. In such instance, further evaluation is recommended to exclude the liver disease. Early recognition and treatment of coeliac disease in patients affected by liver disease are important to improve the liver function and prevent complications.

Hepatitis B vaccine in celiac disease: Yesterday, today and tomorrow

Some studies showed that in celiac patients the immunological response to vaccination is similar to that one found in general population except for vaccine against hepatitis B virus (HBV). The non-responsiveness to HBV vaccine has also been described in healthy people, nevertheless the number of non-responders has been demonstrated to be higher in celiac disease (CD) patients than in healthy controls. Several hypothesis explaining this higher rate of unresponsiveness to HBV vaccine in CD patients have been described, such as the genetic hypothesis, according with CD patients carrying the disease-specific haplotype HLA-B8, DR3, and DQ2, show a lower response to HBV vaccine both in clinical expressed CD patients and in healthy people carrying the same haplotype. On the other hand, it has been demonstrated that the gluten intake during the vaccination seems to influence the response to the same vaccine. Moreover, it has been demonstrated a possible genetic predisposition to hepatitis B vaccine non-responsiveness likely due to the presence of specific human leukocyte antigen haplotypes and specific single nucleotide polymorphism in genes of cytokine/cytokine receptors and toll like receptors, but the pathogenic mechanism responsible for this low responsiveness still remains unclear. The aim of this review is to focus on the possible pathogenic causes of unresponsiveness to HBV vaccine in CD patients and to propose an alternative vaccination schedule in order to improve the responsiveness to HBV vaccine in this at-risk patients.

Pathophysiology of celiac disease

Celiac disease results from the interplay of genetic, environmental, and immunologic factors. An understanding of the pathophysiology of celiac disease, in which the trigger (wheat, rye, and barley) is known, will undoubtedly reveal basic mechanisms that underlie other autoimmune diseases (eg, type 1 diabetes) that share many common pathogenic perturbations. This review describes seminal findings in each of the 3 domains of the pathogenesis of celiac disease, namely genetics, environmental triggers, and immune dysregulation, with a focus on newer areas of investigation such as non-HLA genetic variants, the intestinal microbiome, and the role of the innate immune system.

Coeliac disease and C virus-related chronic hepatitis: a non association

BACKGROUND

A higher prevalence of coeliac disease has recently been reported among patients with HCV-related chronic hepatitis. Moreover, development of clinically overt coeliac disease has been described in a number of HCV-related chronic hepatitis patients during α-interferon therapy. This prospective study was designed to evaluate 1) the prevalence of coeliac disease in patients with HCV-related chronic hepatitis; 2) the prevalence of HCV infection in patients with coeliac disease; 3) whether PEG interferon-α treatment might favour the development of coeliac disease in patients with chronic hepatitis C.

MATERIALS AND METHODS

Two hundred-ten consecutive patients (M/F = 140/70, range of age 35-58 years, median age 46.5 years) with biopsy proven chronic hepatitis C underwent serological screening for antiendomysial and tissue transglutaminase IgA antibodies. One hundred ninety-four coeliac patients (M/F = 52/142, range of age 18-74 years, median age 34 years) were screened for HCV antibodies. Positivity for HCV antibodies in coeliac disease patients was confirmed by detection of serum HCV-RNA by RT-PCR. This work was carried out in accordance to ethical guidelines of Declaration of Helsinki and was approved by Institutional Ethics Committee of the Second University of Naples. All patients gave informed written consent.

RESULTS

1) none of the 210 HCV-related chronic hepatitis patients were positive for coeliac disease serologic screening; 2) prevalence of HCV infection among coeliac patients was 1.54% (3/194) which is comparable to that reported in the Southern Italy population; 3) PEG interferon-α treatment was not associated with development of coeliac disease either clinical or serological.

CONCLUSIONS

1) coeliac disease is not associated with HCV infection; 2) PEG interferon-α does not trigger celiac disease.

The adaptive immune response in celiac disease

Compared to other human leukocyte antigen (HLA)-associated diseases such as type 1 diabetes, multiple sclerosis, and rheumatoid arthritis, fundamental aspects of the pathogenesis in celiac disease are relatively well understood. This is mostly because the causative antigen in celiac disease-cereal gluten proteins-is known and the culprit HLA molecules are well defined. This has facilitated the dissection of the disease-relevant CD4+ T cells interacting with the disease-associated HLA molecules. In addition, celiac disease has distinct antibody responses to gluten and the autoantigen transglutaminase 2, which give strong handles to understand all sides of the adaptive immune response leading to disease. Here we review recent developments in the understanding of the role of T cells, B cells, and antigen-presenting cells in the pathogenic immune response of this instructive disorder.

Immunomodulatory functions of type I interferons

Interferon-α (IFNα) and IFNβ, collectively known as type I IFNs, are the major effector cytokines of the host immune response against viral infections. However, the production of type I IFNs is also induced in response to bacterial ligands of innate immune receptors and/or bacterial infections, indicating a broader physiological role for these cytokines in host defence and homeostasis than was originally assumed. The main focus of this Review is the underappreciated immunomodulatory functions of type I IFNs in health and disease. We discuss their function in the regulation of innate and adaptive immune responses, the response to bacterial ligands, inflammasome activation, intestinal homeostasis and inflammatory and autoimmune diseases.

Is it time to screen for adult coeliac disease?

To meet the principles of screening as described by Wilson and Jungner a disease must be common, a significant health burden, detectable and treatable. The key lies in the early detection and alteration of the natural history of disease. Coeliac disease affects 1 in 100 people. Despite this patients frequently have delays in diagnosis or may remain undetected. There is an associated morbidity and mortality which can be effectively treated by simple means of a gluten-free diet. For these reasons coeliac disease has been suggested as appropriate for mass screening. However, there are caveats to this: a complex clinical spectrum, a natural history that is imperfectly understood, overestimation of morbidity and mortality, poor adherence to treatment, and costs of service provision may argue against the time being right for mass screening. This review article provides the most contemporary overview and reference base to allow any clinician to understand the benefits or limitations of a screening programme for adult coeliac disease.

Integration of genetic and immunological insights into a model of celiac disease pathogenesis

Celiac disease (CD) is a gluten-sensitive enteropathy that develops in genetically susceptible individuals by exposure to cereal gluten proteins. This review integrates insights from immunological studies with results of recent genetic genome-wide association studies into a disease model. Genetic data, among others, suggest that viral infections are implicated and that natural killer effector pathways are important in the pathogenesis of CD, but most prominently these data converge with existing immunological findings that CD is primarily a T cell-mediated immune disorder in which CD4(+) T cells that recognize gluten peptides in the context of major histocompatibility class II molecules play a central role. Comparison of genetic pathways as well as genetic susceptibility loci between CD and other autoimmune and inflammatory disorders reveals that CD bears stronger resemblance to T cell-mediated organ-specific autoimmune than to inflammatory diseases. Finally, we present evidence suggesting that the high prevalence of CD in modern societies may be the by-product of past selection for increased immune responses to combat infections in populations in which agriculture and cereals were introduced early on in the post-Neolithic period.

Association between Celiac Disease and Chronic Hepatitis C Virus Infection

Celiac disease affects the proximal small intestine and is caused by a local immune response to dietary gluten. Celiac disease usually presents with chronic diarrhea; however, presentations with elevated hepatic transaminase levels in blood or with iron-deficiency anemia have been described. Celiac disease has been reported to be associated with autoimmune liver diseases. Hepatitis C virus (HCV) can also initiate autoimmune disease process. Therefore, HCV infection and celiac disease may occur together. Here, we describe 4 cases of celiac disease associated with chronic hepatitis C. This small case series indicates that chronic HCV infection and celiac disease are not causally associated.

Adaptive T-cell responses regulating oral tolerance to protein antigen

The term oral (or mucosal) tolerance has been classically defined as the suppression of T- and B-cell responses to an antigen by prior administration of the antigen by the oral route. In recent years, it has become clear that both innate and acquired regulatory immune responses are essential for the development of oral tolerance. As such, mucosal microenvironmental factors such as transforming growth factor- β, prostaglandins but also dietary vitamin A create conditioning of an adaptive regulatory T-cell response that suppresses subsequent antigen-specific responses. Particular resident subsets of antigen presenting dendritic cells are pivotal to convey conditioning signals next to the presentation of antigen. This review discusses the primary mechanisms of adaptive regulatory T-cell induction to ingested soluble protein antigen. However, we also discuss the limitations of our knowledge with respect to understanding the very common food hypersensitivity Celiac disease caused by an aberrant adaptive immune response to the food protein gluten.

Tissue-mediated control of immunopathology in coeliac disease

Coeliac disease is an inflammatory disorder with autoimmune features that is characterized by destruction of the intestinal epithelium and remodelling of the intestinal mucosa following the ingestion of dietary gluten. A common feature of coeliac disease and many organ-specific autoimmune diseases is a central role for T cells in causing tissue destruction. In this Review, we discuss the emerging hypothesis that, in coeliac disease, intestinal tissue inflammation--induced either by infectious agents or by gluten--is crucial for activating T cells and eliciting their tissue-destructive effector functions.

A review of adverse cutaneous drug reactions resulting from the use of interferon and ribavirin

Drug-induced cutaneous eruptions are named among the most common side effects of many medications. Thus, cutaneous drug eruptions are a common cause of morbidity and mortality, especially in hospital settings. The present article reviews different presentations of drug-induced cutaneous eruptions, with a focus on eruptions reported secondary to the use of interferon and ribavirin. Presentations include injection site reactions, psoriasis, eczematous drug reactions, alopecia, sarcoidosis, lupus, fixed drug eruptions, pigmentary changes and lichenoid eruptions. Also reviewed are findings regarding life-threatening systemic drug reactions.

[Onset of celiac disease after acute hepatitis B infection]

Celiac disease is characterized by small intestinal mucosal injury and nutrient malabsorption in genetically susceptible individuals following dietary ingestion of gluten. The pathogenesis of the disease involves interactions between environmental, genetic, and immunologic factors. Transient infections or increased permeability of the mucosa may facilitate disease onset induced by the uptake of gluten peptides into a microenvironmental milieu in the small intestinal mucosa. We present two patients with onset of celiac disease after resolution of acute hepatitis B virus infection. The physiopathology of celiac disease is discussed and possible explanations for this association are proposed.

Thyroid disorders and occurrence of nonorgan-specific autoantibodies (NOSA) in patients with chronic hepatitis C before and during antiviral induction therapy with consensus interferon (interferon alfacon-1)

BACKGROUND AND AIM

Thyroid disorders represent a common side effect of antiviral therapy in patients with chronic hepatitis C (CHC). However, there is strong evidence for a higher prevalence of thyroidal antibodies (TA) and nonorgan-specific autoantibodies (NOSA) even before interferon (IFN) administration. Here, we report for the first time on the distribution and occurrence of TA and NOSA before, during, and after treatment with daily highdosed IFN alfacon-1 [consensus IFN (CIFN)].

METHODS

Thyrotropin (TSH) levels and antibodies to different autoantigens were analyzed in 217 patients with CHC (29.8% females) who were treated with CIFN induction therapy (27 or 18 mg q.d.).

RESULTS

Pretreatment abnormal TSH levels (TSH>3.0 mU/L or <0.4 mU/L) were detected in 15.6% and occurred significantly more often in females (24.6%; P=0.018). TA could be detected only in 2.6%, NOSA in up to 29.9% (47.4% females vs. 24.2% males). During CIFN induction therapy, low TSH levels were detected in 14.1% whereas elevated TSH levels occurred later (week 48) in up to 15.5%, again preferentially in females (42%, P=0.005). In 1.4% of all patients, treatment had to be discontinued because of symptomatic hyperthyroidism. TAs were detected in 10.5% (30.5% females) and NOSA up to 58% during CIFN treatment.

CONCLUSIONS

During CIFN induction therapy, alterations in TSH levels and an increased prevalence of TA and NOSA are quite common, especially in females. Clinically relevant symptoms occur, however, only in a small number (1.4%). Thus, treatment with daily and high-dose CIFN does not appear to increase the incidence of (severe) thyroidal or other autoimmune disorders compared with standard IFN in patients with CHC.

Coeliac disease

Coeliac disease is a chronic inflammatory disorder of the small bowel induced in genetically susceptible people by the irritant gluten and possibly other environmental cofactors. The disorder is characterised by a diverse clinical heterogeneity that ranges from asymptomatic to severely symptomatic, and it manifests with frank malabsorption, an increased morbidity attributable to the frequent association with autoimmune disorders and increased mortality resulting from the emergence of T-cell clonal proliferations that predispose the patient to enteropathy-type T-cell lymphoma. Our understanding of the molecular basis for this disorder has improved and enabled the identification of targets for new therapies, although a strict gluten-free diet remains the mainstay of safe and effective treatment. In this Seminar we critically reassess the clinical and diagnostic aspects of this disease and new perspectives in its pathogenesis and treatment.