Celiac disease - a pluripathological model in pediatric practice

Being defined as an autoimmune, chronic pathology, frequently encountered in any age group, but especially in pediatrics, celiac disease (also called gluten enteropathy), is gaining more and more ground in terms of diagnosis, but also interest in research. The data from the literature of the last decades attest the chameleonic way of its presentation, there may be both classic onset symptoms and atypical symptoms. Given the impact played by celiac disease, especially in the optimal growth and development of children, the current narrative review aims to highlight the atypical presentation methods, intended to guide the clinician towards the inclusion of the pathology in the differential diagnosis scheme. To these we add the summary presentation of the general data and therapeutic lines regarding the underlying condition and the existing comorbidities. In order to place the related information up to date, we performed a literature review of the recent articles published in international databases. We bring forward the current theories and approaches regarding both classic celiac disease and its atypical manifestations. Among these we note mainly constitutional, skin or mucous, bone, neuro-psychic, renal, reproductive injuries, but also disorders of biological constants and association with multiple autoimmunities. Knowing and correlating them with celiac disease is the key to optimal management of patients, thus reducing the subsequent burden of the disease.

Assessment of Nutritional Status by Bioelectrical Impedance in Adult Patients with Celiac Disease: A Prospective Single-Center Study

The gluten-free diet [GFD] has been linked to an increased risk of weight gain and the development of metabolic disorders. Most of the studies have focused on the effect of GFD on the Body Mass Index [BMI]. We aimed to evaluate the nutritional status using specific nutritional parameters in patients with celiac disease [CeD] at diagnosis and on a GFD compared to healthy controls. We recruited subjects at our outpatient clinic at the University of Padua. We collected demographic and clinical data and values obtained with bioelectrical impedance analysis. A total of 24 CeD patients and 28 healthy controls were enrolled. CeD patients at diagnosis had a lower body cell mass index [BCMI, p = 0.006], fat-free mass index [FFMI, p = 0.02], appendicular skeletal muscle index [ASMI, p = 0.02], and phase angle [PA] [p < 0.001] compared to controls. Their percentage of extracellular water [ECW] was also higher [p < 0.001]. Considering CeD patients after GFD, nutritional status significantly improved after 6 months of GFD. We did not observe differences in BMI among groups [p = ns]. CeD patients at diagnosis were found to have a poorer nutritional status than healthy controls, with a positive effect of the GFD on their nutritional status, underlining the inefficacy of evaluating this aspect through only BMI evaluation.

Genetically modified rodent models and celiac, non-celiac gluten sensitivity: a minireview

Celiac disease (CD) is a disorder that affects both children and adults. Over the few last decades, several new atypical cases have been identified through improved diagnostic tools. On the other hand, the onset of CD at a later age, including atypical CD forms whose clinical picture overlaps with other autoimmune diseases, shows that currently there are several unknown gene mutations, which could be responsible for the disease development. Non-celiac gluten sensitivity (NCGS) is entity included by the ingestion of gluten leading to intestinal, or extraintestinal symptoms that improve once the gluten is removed from the nutrition. In this article relationships between genetically modified rodent animals with previously unknown multiple organ changes and CD, respectively NCGS are reviewed. Relationships between the small bowel histological changes and other organs pathology are discussed. Results of research document that changes have similar genetic background and can develop to serious autoimmune systematic diseases, including small bowel inflammation resembling atypical CD or NCGS. These may have extra-intestinal symptomatology but without a clear explanation of causes and differences in their manifestations. Research on animal models helps to discover links between several disorders associated with gastrointestinal damage. New methods based on individual gene mutations can help in atypical adult CD and NCGS recognitions in the future.

Healthcare Resource Utilization and Costs in Celiac Disease: A US Claims Analysis

INTRODUCTION

Celiac disease (CeD) is a lifelong immune-mediated enteropathy in which dietary gluten triggers an inflammatory reaction in the small intestine. This retrospective cohort study examines healthcare resource utilization (HRU) and costs between patients with CeD and matched controls.

METHODS

Patients with CeD (cases) with an endoscopic biopsy and ≥2 medical encounters with a CeD diagnosis between January 1, 2010, and October 1, 2015, were identified in the MarketScan databases. The date of the first claim with a CeD diagnosis on or after the endoscopic biopsy was the index date. Cases were matched 1:1 to patients without CeD (controls) on demographic characteristics and Deyo-Charlson Comorbidity Index score. Clinical characteristics, all-cause, and CeD-related HRU and costs (adjusted to 2017 US dollars) were compared between cases and controls during the 12 months before (baseline) and 24 months after (follow-up) the index date.

RESULTS

A total of 11,008 cases (mean age 40.6 years, 71.3% women) were matched to 11,008 controls. During the follow-up, a higher proportion of cases had all-cause and CeD-related HRU including inpatient admissions, emergency department visits, gastroenterologist visits, dietician visits, endoscopic biopsies, and gastroenterology imaging (all P ≤ 0.002). Incremental all-cause and CeD-related costs were in the first ($7,921 and $2,894) and second ($3,777 and $935) year of follow-up, driven by outpatient services costs.

DISCUSSION

In this US national claims database analysis, there was evidence of an increase in both all-cause and CeD-related HRU and related costs in patients with CeD compared with matched patients without CeD, suggesting a significant economic burden associated with CeD.

A Comprehensive Review of Celiac Disease/Gluten-Sensitive Enteropathies

Celiac disease is a complex immune-mediated gluten-sensitive enteropathy with protean clinical manifestations. It is manifest in genetically predisposed individuals who ingest gluten in varying amounts. In broad terms, it is thought to affect 1% of the population in the USA. More specifically, the prevalence increases drastically from 1:133 in patients not-at-risk, to 1:56 in symptomatic patients, to 1:39 in patients with a second-degree relative with the diagnosis, and to 1:22 in patients with a first-degree relative with the diagnosis. It may be associated with several immune-mediated phenomena, autoimmune diseases, and complicated by vitamin and other trace element deficiencies, bone disease, and malignancy. Our understanding of celiac disease has evolved rapidly over the past two decades. This has led to several lines of enquiry on the condition and potential treatment options. More recently, several entities including gluten intolerance, non-celiac gluten sensitivity, and seronegative celiac disease have been described. These conditions are distinct from allergies or intolerance to wheat or wheat products. There are challenges in defining some of these entities since a large number of patients self-report these conditions. The absence of confirmatory diagnostic tests poses an added dilemma in distinguishing these entities. The differences in spectrum of symptoms and highlights of the variability between the pediatric and adult populations have been studied in some detail. The role of screening for celiac disease is examined in both the general population and "at risk" populations. Diagnostic strategies including the best available serologic testing, utility of HLA haplotypes DQ2 and DQ8 which are seen in over 90% of patients with celiac disease as compared with approximately 40% of the general population, and endoscopic evaluation are also reviewed. Comprehensive nutritional management after diagnosis is key to sustained health in patients with celiac disease. Simple algorithms for care based on a comprehensive multidisciplinary approach are proposed. Refractory and non-responsive celiac diseases in the setting of a gluten-free diet are examined as are novel non-dietary therapies. Finally, the association of other disease states including psychiatric illness, infertility, lymphoproliferative malignancy, and mortality is explored with special attention paid to autoimmune and atopic disease.

Hypoalbuminemia and generalized edema as an atypical presentation of celiac disease

The clinical presentation of celiac disease has evolved significantly over the last few decades. Previously defined as a malabsorption syndrome in pediatric patients, now it is considered an autoimmune disorder with diverse systemic manifestations among all age groups. We report a case of 56-year-old male presented with pedal edema and gradually progressive abdomen distention for the last 3 months. Serological evaluation and duodenal biopsy reports were suggestive of celiac disease. The patient was advised gluten-free diet, after 12 weeks, the patient became asymptomatic with the resolution of ascites and peripheral edema. According to the literature, there are few reports of protein-losing enteropathy as an initial presentation of celiac disease. The possibility of celiac disease should be considered even in the setting of atypical symptoms.

Management of celiac disease in daily clinical practice

Celiac disease (CD) is the most common autoimmune enteropathy worldwide. In CD, dietary gluten triggers a T cell driven small intestinal inflammation in a subset of genetically predisposed subjects, expressing the HLA DQ2 and/or DQ8 genes on their antigen presenting cells. HLA DQ2/DQ8 can bind gluten peptides after their prior modification by the CD autoantigen, tissue transglutaminase (TG2). This process leads to the activation of gluten reactive T cells, small bowel villous atrophy, crypt hyperplasia and intraepithelial lymphocytosis, the histological hallmarks of CD. The clinical picture of CD is extremely heterogeneous including intestinal (especially diarrhea, abdominal pain, bloating) and extraintestinal (especially associated autoimmune diseases, anemia, osteoporosis) manifestations. The prevalence of CD in most parts of the world is estimated at 1:100-1:150 and its diagnosis is based on the presence of circulating autoantibodies (anti-TG2) and the histological detection of villous atrophy. Treatment is a lifelong gluten free diet but adjunctive therapies are in development. Although CD is a well-characterized disease, it is grossly underdiagnosed, despite the severe consequences of long-term gluten ingestion in CD, such as enhanced autoimmunity, refractory CD and intestinal T cell lymphoma. The aim of the presented review is to provide a clinical guide and to summarize the most recent clinical progress in CD research.

Coeliac disease

Coeliac disease occurs in about 1% of people in most populations. Diagnosis rates are increasing, and this seems to be due to a true rise in incidence rather than increased awareness and detection. Coeliac disease develops in genetically susceptible individuals who, in response to unknown environmental factors, develop an immune response that is subsequently triggered by the ingestion of gluten. The disease has many clinical manifestations, ranging from severe malabsorption to minimally symptomatic or non-symptomatic presentations. Diagnosis requires the presence of duodenal villous atrophy, and most patients have circulating antibodies against tissue transglutaminase; in children, European guidelines allow a diagnosis without a duodenal biopsy provided that strict symptomatic and serological criteria are met. Although a gluten-free diet is an effective treatment in most individuals, a substantial minority develop persistent or recurrent symptoms. Difficulties adhering to a gluten-free diet have led to the development of non-dietary therapies, several of which are undergoing trials in human beings.

Prior Misdiagnosis of Celiac Disease Is Common Among Patients Referred to a Tertiary Care Center: A Prospective Cohort Study

OBJECTIVES

Interest of patients and physicians in celiac disease is growing worldwide, but without a corresponding increase in the awareness of the disease. Many patients are diagnosed as celiacs even without completing the whole diagnostic process, with consequent risk of misdiagnosis and delay in the evaluation of other diseases. The objective of this study was to assess the rates of prior celiac disease misdiagnosis among patients referred to a tertiary care center.

METHODS

From June 2013 to December 2014, we prospectively recruited patients referred for the first time to our Celiac Disease Center. Patients with a previous diagnosis of celiac disease underwent a diagnostic revaluation by second reading of duodenal tissue slides, dosage of specific antibodies, and/or duodenal biopsy sampling; HLA status was investigated in pertinent cases.

RESULTS

A total of 198 subjects were recruited. Of these, 91 "naïve" patients (46%) started the diagnostic screening for celiac disease; 58 of them (64-29% of the whole sample) were diagnosed as celiacs. The remaining 107 patients (54%) came with a previous diagnosis of celiac disease: of these, 52 (49-26% of the whole sample) presented with confirmed diagnosis of celiac disease, whereas 55 (51-28% of the whole sample) underwent diagnostic revaluation. After the reassessment, diagnosis was rejected in 43 cases (78-22% of the whole sample) and confirmed in the remaining 12 (22-6% of the whole sample). Overall, diagnosis was confirmed in only 64 of the 107 subjects with a previous diagnosis (60-32% of the whole sample). Diagnosis of celiac disease was more frequently confirmed in "naïve" patients compared those with a questionable previous diagnosis (64% vs. 22%; P<0.0001).

CONCLUSIONS

A considerable number of patients referred to a tertiary care center are inaccurately diagnosed with celiac disease. Although we cannot exclude that uncertain diagnosis was a reason for the referral, we suggest greater adherence to guidelines to minimize the burden of celiac disease misdiagnosis.

Seronegative Celiac Disease and Immunoglobulin Deficiency: Where to Look in the Submerged Iceberg?

In the present narrative review, we analyzed the relationship between seronegative celiac disease (SNCD) and immunoglobulin deficiencies. For this purpose, we conducted a literature search on the main medical databases. SNCD poses a diagnostic dilemma. Villous blunting, intraepithelial lymphocytes (IELs) count and gluten "challenge" are the most reliable markers. Immunohistochemistry/immunofluorescence tissue transglutaminase (tTG)-targeted mucosal immunoglobulin A (IgA) immune complexes in the intestinal mucosa of SNCD patients may be useful. In our experience, tTG-mRNA was similarly increased in seropositive celiac disease (CD) and suspected SNCD, and strongly correlated with the IELs count. This increase is found even in the IELs' range of 15-25/100 enterocytes, suggesting that there may be a "grey zone" of gluten-related disorders. An immune deregulation (severely lacking B-cell differentiation) underlies the association of SNCD with immunoglobulin deficiencies. Therefore, CD may be linked to autoimmune disorders and immune deficits (common variable immunodeficiency (CVID)/IgA selective deficiency). CVID is a heterogeneous group of antibodies dysfunction, whose association with CD is demonstrated only by the response to a gluten-free diet (GFD). We hypothesized a familial inheritance between CD and CVID. Selective IgA deficiency, commonly associated with CD, accounts for IgA-tTG seronegativity. Selective IgM deficiency (sIgMD) is rare (<300 cases) and associated to CD in 5% of cases. We diagnosed SNCD in a patient affected by sIgMD using the tTG-mRNA assay. One-year GFD induced IgM restoration. This evidence, supporting a link between SNCD and immunoglobulin deficiencies, suggests that we should take a closer look at this association.

New approaches in hepatitis B vaccination for celiac disease

Celiac disease (CD) is a gluten-induced immune-mediated disorder that has been associated with a defective response to the hepatitis B virus (HBV) vaccination. This unresponsiveness could lead to a world health problem, because non-responder patients could represent a reservoir of HBV-susceptible people that will persist as healthy carriers, leading to the diffusion of the disease. This article presents a literature review of both intramuscular (IM) and intradermal (ID) routes for boosters in celiac patients. We used PubMed database and generated the odds ratio (OR) of the response on the basis of electronic searches of clinical trials. Although our results confirm the positive response of celiac patients to IM vaccination, the ID route seems to be better than the conventional one, since it could provide a saving in cost and a greater immunogenicity.

The challenges in defining and measuring diagnostic error

Diagnostic errors have emerged as a serious patient safety problem but they are hard to detect and complex to define. At the research summit of the 2013 Diagnostic Error in Medicine 6th International Conference, we convened a multidisciplinary expert panel to discuss challenges in defining and measuring diagnostic errors in real-world settings. In this paper, we synthesize these discussions and outline key research challenges in operationalizing the definition and measurement of diagnostic error. Some of these challenges include 1) difficulties in determining error when the disease or diagnosis is evolving over time and in different care settings, 2) accounting for a balance between underdiagnosis and overaggressive diagnostic pursuits, and 3) determining disease diagnosis likelihood and severity in hindsight. We also build on these discussions to describe how some of these challenges can be addressed while conducting research on measuring diagnostic error.

Food-derived opioid peptides inhibit cysteine uptake with redox and epigenetic consequences

Dietary interventions like gluten-free and casein-free diets have been reported to improve intestinal, autoimmune and neurological symptoms in patients with a variety of conditions; however, the underlying mechanism of benefit for such diets remains unclear. Epigenetic programming, including CpG methylation and histone modifications, occurring during early postnatal development can influence the risk of disease in later life, and such programming may be modulated by nutritional factors such as milk and wheat, especially during the transition from a solely milk-based diet to one that includes other forms of nutrition. The hydrolytic digestion of casein (a major milk protein) and gliadin (a wheat-derived protein) releases peptides with opioid activity, and in the present study, we demonstrate that these food-derived proline-rich opioid peptides modulate cysteine uptake in cultured human neuronal and gastrointestinal (GI) epithelial cells via activation of opioid receptors. Decreases in cysteine uptake were associated with changes in the intracellular antioxidant glutathione and the methyl donor S-adenosylmethionine. Bovine and human casein-derived opioid peptides increased genome-wide DNA methylation in the transcription start site region with a potency order similar to their inhibition of cysteine uptake. Altered expression of genes involved in redox and methylation homeostasis was also observed. These results illustrate the potential of milk- and wheat-derived peptides to exert antioxidant and epigenetic changes that may be particularly important during the postnatal transition from placental to GI nutrition. Differences between peptides derived from human and bovine milk may contribute to developmental differences between breastfed and formula-fed infants. Restricted antioxidant capacity, caused by wheat- and milk-derived opioid peptides, may predispose susceptible individuals to inflammation and systemic oxidation, partly explaining the benefits of gluten-free or casein-free diets.

Diagnosis of celiac disease in adults based on serology test results, without small-bowel biopsy

BACKGROUND & AIMS

Celiac disease is underdiagnosed, with nonspecific symptoms and high morbidity. New diagnostic factors are needed. We aimed to estimate the frequency at which adult patients with positive results from serology tests are referred for small-bowel biopsies and to identify factors that improve the diagnosis of celiac disease.

METHODS

We performed a retrospective analysis of data from 2477 subjects who received serology tests for celiac disease between 2005 and 2007. We analyzed results for total levels of IgA, IgA against human tissue transglutaminase (hTTG), IgA and IgG against gliadin, as well as dilution titers of IgA against endomysial antibodies (EMA). Biopsy samples were analyzed by pathologists experienced in detecting mucosal changes associated with celiac disease and graded according to the Marsh system.

RESULTS

Of the 2477 patients, 610 (25%) had abnormal results from serology tests, and 39% of these patients (240 of 610) underwent small-bowel biopsy analyses. Of these patients, 50 (21%) had biopsy findings consistent with celiac disease (Marsh 3 lesions) and were placed on gluten-free diets. Titers of IgA hTTG greater than 118 U identified patients with celiac disease with a 2% false-positive rate. Titers of 21 to 118 U, in combination with an EMA dilution titer of 1:160 or greater, had a positive predictive value of 83% for celiac disease. IgA hTTG levels less than 20 U, in combination with an EMA dilution titer less than 1:10, had a negative predictive value of 92% for celiac disease.

CONCLUSIONS

Serum levels of IgA hTTG greater than 118 U, or 21 to 118 U in combination with an EMA dilution titer of 1:160 or greater, can be used to identify adult symptomatic patients with celiac disease, in the absence of a small-bowel biopsy.

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.

Serology in adults with celiac disease: limited accuracy in patients with mild histological lesions

Celiac disease (CD) is a gluten-triggered enteropathy, presenting with insidious clinical patterns. It can occasionally be diagnosed in asymptomatic subjects. Our aim was to define the relationship among symptoms at diagnosis, serological markers [tissue transglutaminase antibodies (tTGA), anti-endomysium antibodies (EMA) anti-actin antibodies (AAA)] and degree of mucosal damage. A total of 68 consecutive adult patients with CD were enrolled. Intestinal biopsies were scored according to the Marsh classification modified by Oberhuber: I-II minimal lesions or absent villous atrophy; IIIA partial villous atrophy; IIIB-C total villous atrophy (TVA). HLA-typing was done for all patients. No association between clinical presentation and severity of mucosal damage was found. Presence of EMA or tTGA was significantly associated with more severe mucosal damage (P < 0.001). Of 12 patients, 11 with AAA were also positive for TVA. The severity of mucosal damage is the main factor governing the detectability of serological markers of CD. The sensitivity of serological testing is questionable in patients with minimal lesions.