Intestinal intraepithelial lymphocytes and anti-transglutaminase in a screening algorithm for coeliac disease

Improving the Diagnosis of Dermatitis Herpetiformis Using the Intraepithelial Lymphogram

Dermatitis herpetiformis is a cutaneous manifestation of celiac disease. Phenotyping of intraepithelial lymphocytes in the small bowel mucosa can strengthen the diagnosis of celiac disease when it is not clear-cut. We aim to evaluate the usefulness of the intraepithelial lymphogram to confirm dermatitis herpetiformis in equivocal cases. We performed a retrospective multicenter study on patients diagnosed with dermatitis herpetiformis and collected data from the intraepithelial lymphogram assessed by flow cytometry. A total of 36 patients were analyzed in relation to the severity of intestinal damage (18 had non-atrophic mucosa) at baseline (N = 28) and/or after the adoption of a gluten-free diet (median follow-up of three years, N = 16). We observed that patients with atrophy more often had positive celiac serology (p = 0.019), celiac clinical symptoms (p = 0.018), and iron-deficiency anemia (p = 0.018), but the severity of skin damage was similar in both groups (p = 0.79). At baseline, increased TCRγδ+ cells were present in 94% of patients with atrophy and 67% with non-atrophic lesions (p = 0.13). After a gluten-free diet, increased TCRγδ+ cells persisted in 100% and 63% of cases, respectively (p = 0.21). We concluded that increased TCRγδ+ cells may be helpful in confirming the diagnosis of dermatitis herpetiformis in equivocal cases, even in patients who were started on a gluten-free diet.

Intestinal and blood lymphograms as new diagnostic tests for celiac disease

Accurate celiac disease (CD) diagnosis is still challenging for some specific patients or circumstances. Thus, much effort has been expended last decades focused on seronegative or low grade enteropathy CD and, especially, on enable early diagnosis of individuals on a gluten-free diet (GFD). We discuss here two diagnostic approaches based on immunophenotyping by flow cytometry that we expect to reduce the persistent low diagnostic rates and the common diagnostic delay. The intraepithelial lymphogram is based on determining the percentage of TCRγδ+ and surface CD3- lymphocytes in the intestinal epithelium. The concomitant increase in TCRγδ+ and decrease in surface CD3- intraepithelial lymphocytes has been termed the celiac lymphogram and has been proved to be discriminative in seronegative, low grade enteropathy and potential CD, as well as in most CD patients on a GFD. A blood lymphogram based on the analysis of activated gut-homing CD8+ T cells combined with a 3-day gluten challenge is also considered, which has shown high sensitivity and specificity to diagnose seropositive Marsh 1 and Marsh 3 CD in individuals following a GFD. In addition, flow cytometry can be extremely useful in cases of refractory CD type II to identify aberrant cells. Those approaches represent highly accurate methods for CD diagnosis, being simple, fast, highly reproducible and of easy implementation in clinical practice.

Coeliac Disease in Elderly Patients: Value of Coeliac Lymphogram for Diagnosis

(1) Background: Although a meta-analysis reported that the sensitivity of CD3+ TCRγδ+ cells for coeliac disease diagnosis was >93%, a recent study has suggested that sensitivity decreased to 65% in elderly patients. (2) Aim: To evaluate whether the sensitivity of intraepithelial lymphocyte cytometric patterns for coeliac disease diagnosis changes with advanced age. (3) Methods: We performed a multicentre study including 127 coeliac disease patients ≥ 50 years: 87 with baseline cytometry (45 aged 50–59 years; 23 aged 60–69 years; 19 aged ≥ 70 years), 16 also with a follow-up cytometry (on a gluten-free diet); and 40 with only follow-up cytometry. (4) Results: In Marsh 3 patients, a sensitivity of 94.7%, 88.9% and 86.7% was observed for each age group using a cut-off value of TCRγδ+ >10% (p = 0.27); and a sensitivity of 84.2%, 83.4% and 53.3% for a cut-off value >14% (p = 0.02; 50–69 vs. ≥70 years), with difference between applying a cut-off of 10% or 14% (p = 0.008). The TCRγδ+ count in the ≥70 years group was lower than in the other groups (p = 0.014). (5) Conclusion: In coeliac patients ≥ 70 years, the TCRγδ+ count decreases and the cut-off point of >10% is more accurate than >14%.

Long-Term Effect of a Gluten-Free Diet on Diarrhoea- or Bloating-Predominant Functional Bowel Disease: Role of the 'Low-Grade Coeliac Score' and the 'Coeliac Lymphogram' in the Response Rate to the Diet

1.

BACKGROUND

The long-term effect of a gluten-free diet (GFD) on functional bowel disorders (FBDs) has been scarcely studied. The aim was to assess the effect of a GFD on FBD patients, and to assess the role of both the low-grade coeliac score and coeliac lymphogram in the probability of response to a GFD. 2.

METHODS

116 adult patients with either predominant diarrhoea or abdominal bloating, fulfilling Rome IV criteria of FBD, were treated with a GFD. Duodenum biopsies were performed for both pathology studies and intraepithelial lymphocyte subpopulation patterns. Coeliac lymphogram was defined as an increase in TCRγδ+ cells plus a decrease in CD3- cells. A low-grade coeliac score >10 was considered positive. 3.

RESULTS

Sustained response to GFD was observed in 72 patients (62%) after a median of 21 months of follow-up, who presented more often with coeliac lymphogram (37.5 vs. 11.4%; p = 0.02) and a score >10 (32 vs. 11.4%; p = 0.027) compared to non-responders. The frequency of low-grade coeliac enteropathy was 19.8%. 4.

CONCLUSION

A GFD is effective in the long-term treatment of patients with previously unexplained chronic watery diarrhoea- or bloating-predominant symptoms fulfilling the criteria of FBD. The response rate was much higher in the subgroup of patients defined by the presence of both a positive low-grade coeliac score and coeliac lymphogram.

Systematic Review and Meta-Analysis: Accuracy of Both Gamma Delta+ Intraepithelial Lymphocytes and Coeliac Lymphogram Evaluated by Flow Cytometry for Coeliac Disease Diagnosis

It has been suggested that in doubtful cases of coeliac disease, a high CD3+ T-cell receptor gamma delta+ (TCRγδ+) intraepithelial lymphocyte count increases the likelihood of coeliac disease.

AIM

To evaluate the diagnostic accuracy of both an isolated increase of TCRγδ+ cells and a coeliac lymphogram (increase of TCRγδ+ plus decrease of CD3- intraepithelial lymphocytes) evaluated by flow cytometry in the diagnosis of coeliac disease.

METHODS

The literature search was conducted in MEDLINE and EMBASE. The inclusion criteria were: an article that allows for the construction of a 2 × 2 table of true and false positive and true and false negative values. A diagnostic accuracy test meta-analysis was performed.

RESULTS

The search provided 49 relevant citations, of which 6 were selected for the analysis, which represented 519 patients and 440 controls. Coeliac lymphogram: The pooled S and Sp were 93% and 98%, without heterogeneity. The area under the SROC curve (AUC) was 0.98 (95% CI, 0.97-0.99). TCRγδ+: Pooled S and Sp were both 95%, with significant heterogeneity. The AUC was 0.97 (95% CI, 0.95-0.98). Conclusions: Both TCRγδ+ count and coeliac lymphogram assessed by flow cytometry in duodenal mucosal samples are associated with a high level of diagnostic accuracy for and against coeliac disease.

Gamma-Delta T Lymphocytes in the Diagnostic Approach of Coeliac Disease

GOALS

To validate cut-off values of CD3 T-cell receptor gamma-delta chain (TCRγδ) intraepithelial lymphocyte (IEL) in the (differential) diagnosis of celiac disease (CD).

BACKGROUND

CD is characterized by an increase in gamma-delta IEL (CD3TCRγδ IEL).

STUDY

Percentages were determined by flow cytometric analysis of IELs from small bowel biopsies in 213 CD and 13 potential CD (PCD) patients and in total 112 controls. A cut-off value for percentages of CD3TCRγδ IEL to differentiate active CD and controls was obtained from a receiver operating characteristic curve and implemented in controls and PCD patients.

RESULTS

Percentage of CD3TCRγδ IEL was significantly increased in the majority of CD patients, irrespective of the presence of villous atrophy. A cut-off value of 14% for CD3TCRγδ IEL resulted in 66.3% sensitivity and 96.6% specificity for CD diagnosis (area under the curve, 88.6%).

CONCLUSIONS

A percentage of ≥14% CD3TCRγδ IEL has a high specificity for CD diagnosis and can be of diagnostic help in cases where diagnosis is not straightforward.

The Innate Immune System in the Gastrointestinal Tract: Role of Intraepithelial Lymphocytes and Lamina Propria Innate Lymphoid Cells in Intestinal Inflammation

BACKGROUND

The gastrointestinal tract harbors the largest microbiota load in the human body, hence maintaining a delicate balance between immunity against invading pathogens and tolerance toward commensal. Such immune equilibrium, or intestinal homeostasis, is conducted by a tight regulation and cooperation of the different branches of the immune system, including the innate and the adaptive immune system. However, several factors affect this delicate equilibrium, ultimately leading to gastrointestinal disorders including inflammatory bowel disease. Therefore, here we decided to review the currently available information about innate immunity lymphocyte subsets playing a role in intestinal inflammation.

RESULTS

Intestinal innate lymphocytes are composed of intraepithelial lymphocytes (IELs) and lamina propria innate lymphoid cells (ILCs). While IELs can be divided into natural or induced, ILCs can be classified into type 1, 2, or 3, resembling, respectively, the properties of TH1, TH2, or TH17 adaptive lymphocytes. Noteworthy, the phenotype and function of both IELs and ILCs are disrupted under inflammatory conditions, where they help to exacerbate intestinal immune responses.

CONCLUSIONS

The modulation of both IELs and ILCs to control intestinal inflammatory responses represents a major challenge, as they provide tight regulation among the epithelium, the microbiota, and the adaptive immune system. An improved understanding of the innate immunity mechanisms involved in gastrointestinal inflammation would therefore aid in the diagnosis and further treatment of gastrointestinal inflammatory disorders.

Flow cytometry of duodenal intraepithelial lymphocytes improves diagnosis of celiac disease in difficult cases

BACKGROUND

Diagnosis of celiac disease is difficult when the combined results of serology and histology are inconclusive. Studies using flow cytometry of intraepithelial lymphocytes (IELs) have found that celiac patients have increased numbers of γδ IELs, along with a decrease in CD3-CD103 + IELs.

OBJECTIVE

The objective of this article is to assess the role of flow cytometric analysis of IELs in the diagnosis of celiac disease in difficult cases.

METHODS

A total of 312 patients with suspicion of celiac disease were included in the study. Duodenal biopsy samples were used for histological assessment and for flow cytometric analysis of IELs.

RESULTS

In 46 out of 312 cases (14.7%) the combination of serology and histology did not allow the confirmation or exclusion of celiac disease. HLA typing had been performed in 42 of these difficult cases. Taking into account HLA typing and the response to a gluten-free diet, celiac disease was excluded in 30 of these cases and confirmed in the remaining 12. Flow cytometric analysis of IELs allowed a correct diagnosis in 39 out of 42 difficult cases (92.8%) and had a sensitivity of 91.7% (95% CI: 61.5% to 99.8%) and a specificity of 93.3% (95% CI: 77.9% to 99.2%) for the diagnosis of celiac disease in this setting.

CONCLUSION

Flow cytometric analysis of IELs is useful for the diagnosis of celiac disease in difficult cases.

Intraepithelial lymphocytes subsets in different forms of celiac disease

AIM

The enumeration of intraepithelial lymphocytes subsets (total, γδ, and CD3(-) IELs) by flow cytometry (FCM), named as IEL lymphogram, constitutes a useful tool for celiac disease (CD) diagnosis. The aim of this study was to quantify IELs by FCM and their diagnostic value to differentiate active, silent and potential CD.

METHODS

Prospective study of 60 active and 20 silent CD patients, and 161 controls in which duodenal biopsy and IEL quantification by FCM was performed.

RESULTS

Active and silent CD patients had significant higher levels of both total and γδ IELs than absent CD patients (P < 0.0001 and P < 0.0001, P = 0.012 and P < 0.011; respectively). Active and silent CD patients had significant lower levels of CD3(-) IELs than absent CD patients (P < 0.047 and P < 0.009, respectively). Moreover, they were lower in silent than in active CD patients (P = 0.002). Changes of IELs subsets were more marked in children than adults active CD. The optimal IEL lymphogram cut off values for active CD diagnosis were: ≥10, ≥15 and ≤9 %, and with better performance characteristics for silent CD: ≥ 11, ≥10 and ≤5 %.

CONCLUSION

The evaluation of IELs subsets by FCM is useful to confirm diagnosis of active and silent CD.

Innate Lymphoid Cells Groups 1 and 3 in the Epithelial Compartment of Functional Human Intestinal Allografts

We examined intraepithelial lymphocytes (IELs) in 213 ileal biopsies from 16 bowel grafts and compared them with 32 biopsies from native intestines. During the first year posttransplantation, grafts exhibited low levels of IELs (percentage of CD103(+) cells) principally due to reduced CD3(+) CD8(+) cells, while CD103(+) CD3(-) cell numbers became significantly higher. Changes in IEL subsets did not correlate with histology results, isolated intestine, or multivisceral transplants, but CD3(-) IELs were significantly higher in patients receiving corticosteroids. Compared with controls, more CD3(-) IELs of the grafts expressed CD56, NKp44, interleukin (IL)-23 receptor, retinoid-related orphan receptor gamma t (RORγt), and CCR6. No difference was observed in granzyme B, and CD3(-) CD127(+) cells were more abundant in native intestines. Ex vivo, and after in vitro activation, CD3(-) IELs in grafts produced significantly more interferon (IFN)-γ and IL-22, and a double IFNγ(+) IL-22(+) population was observed. Epithelial cell-depleted grafts IELs were cytotoxic, whereas this was not observed in controls. In conclusion, different from native intestines, a CD3(-) IEL subset predominates in grafts, showing features of natural killer cells and intraepithelial ILC1 (CD56(+) , NKp44(+) , CCR6(+) , CD127(-) , cytotoxicity, and IFNγ secretion), ILC3 (CD56(+) , NKp44(+) , IL-23R(+) , CCR6(+) , RORγt(+) , and IL-22 secretion), and intermediate ILC1-ILC3 phenotypes (IFNγ(+) IL-22(+) ). Viability of intestinal grafts may depend on the balance among proinflammatory and homeostatic roles of ILC subsets.

Increased Intraepithelial Vα24 Invariant NKT Cells in the Celiac Duodenum

Celiac Disease (CD) is an interferon (IFN)γ-mediated duodenal hypersensitivity to wheat gluten occurring in genetically predisposed individuals. Gluten-free diet (GFD) leads to a complete remission of the disease. Vα24-restricted invariant NKT (iNKT) cells are important to maintain immune homeostasis in the gut mucosa because of their unique capacity to rapidly produce large quantities of both T-helper (Th)1 and Th2 cytokines upon stimulation. We studied the presence of these cells in the CD duodenum. Duodenal biopsies were obtained from 45 untreated-CD patients (uCD), 15 Gluten Free Diet-CD patients (GFD-CD), 44 non-inflamed non-CD controls (C-controls) and 15 inflamed non-CD controls (I-controls). Two populations from Spain and Argentina were recruited. Messenger RNA (mRNA) expression of Vα24-Jα18 (invariant TCRα chain of human iNKT cells), IFNγ and intracellular transcription factor Forkhead Box P3 (Foxp3), and flow cytometry intraepithelial lymphocyte (IEL) profile were determined. Both uCD and GFD-CD patients had higher Vα24-Jα18 mRNA levels than non-CD controls (I and C-controls). The expression of Vα24-Jα18 correlated with Marsh score for the severity of mucosal lesion and also with increased mRNA IFNγ levels. uCD and GFD-CD patients had decreased mRNA expression of FoxP3 but increased expression of Vα24-Jα18, which revealed a CD-like molecular profile. Increased numbers of iNKT cells were confirmed by flow cytometry within the intraepithelial lymphocyte compartment of uCD and GFD-CD patients and correlated with Vα24-Jα18 mRNA expression. In conclusion, we have found an increased number of iNKT cells in the duodenum from both uCD and GFD-CD patients, irrespective of the mucosal status. A CD-like molecular profile, defined by an increased mRNA expression of Vα24-Jα18 together with a decreased expression of FoxP3, may represent a pro-inflammatory signature of the CD duodenum.

Distal duodenum versus duodenal bulb: intraepithelial lymphocytes have something to say in celiac disease diagnosis

BACKGROUND AND AIM

After clinical screening and the serological test, many patients still require a duodenal biopsy for celiac disease diagnosis. Mild histological lesions, unspecific findings and patchiness are frequent outcomes of this mandatory diagnostic tool, thus complicating clinical decisions.

METHODS

We analyzed the lymphoid components [number of total intraepithelial lymphocytes (IELs), TcR-γδ and CD3(-)IELs] of the duodenal epithelium by flow cytometry in samples obtained from bulb and distal duodenum during upper gastrointestinal endoscopies performed for diagnostic purposes.

RESULTS

IEL counts and IEL subset distribution (IEL lymphogram) remain invariant along duodenal mucosa revealing a specific profile (immunophenotype) that characterizes either a healthy mucosa or a celiac mucosa. The celiac immunophenotype persists regardless of the biopsy's anatomical location or the corresponding histological findings.

CONCLUSIONS

We propose the IEL lymphogram by flow cytometry as an immunological parameter to discern celiac condition from healthy mucosa. This obviates not only misinterpretation of minor histological changes, but also patchiness and the concerns about the location and number of biopsies.

Flow cytometry of intestinal intraepithelial lymphocytes in celiac disease

This article reviews the multiple uses of flow cytometry in the diagnosis, monitoring and research of celiac disease, the most prevalent chronic autoimmune gastrointestinal disease. The phenotyping of intraepithelial lymphocytes (IELs) is of clinical relevance in the diagnosis of the disease given the characteristic features of elevated CD3+ IELs (αβ and γδ TcR) and the decrease in CD3- IELs. IEL biomarkers are also useful in the assessment of the response to the gluten-free diet and, importantly, in the diagnosis of the severe complications of celiac disease: refractory celiac disease and enteropathy-associated T-cell lymphoma. Novel applications of flow cytometry for the detection of anti-transglutaminase antibodies (a validated biomarker of celiac disease) and of gluten (the triggering antigen of the autoimmune process) are also discussed. The assessment of diagnostic and prognostic biomarkers by flow cytometry in celiac disease is performed routinely in a growing number of centers and it is an example of the versatility of this technique and its applicability to the research and clinical study of solid tissues.

Age-related variation of intraepithelial lymphocytes subsets in normal human duodenal mucosa

The enumeration of intestinal intraepithelial lymphocytes (IELs), and the phenotyping of CD3+CD 103+ (TcRalphabeta, TcRgammadelta) and CD3-CD103+ IEL subsets constitute useful diagnostic tools for the correct interpretation of the mucosal histology of duodenal/jejunal biopsies in many pathological conditions of the small intestine, particularly celiac disease (CD). This work evaluates the ranges of duodenal IEL counts by flow cytometry in healthy mucosa from pediatric and adult controls, establishing normal reference values for CD3+ TcRgammadelta and CD3- subsets and their variation with age. Seventy-four pediatric controls and 36 adult controls were identified on the basis of their normal histology from more than 1,000 duodenal diagnostic biopsies performed in Caucasian subjects. Total IEL counts and IEL subsets ("IEL lymphogram") were analyzed by four-color flow cytometry (FCM). IEL represent 7.7% +/- 0.4 (mean +/- SE) and 8.5% +/- 0.5 of the cells isolated from the epithelium in the pediatric and adult series, respectively. The upper normal range, considered as the 97 percentile, is 14% in pediatrics and 15% in adults. No significant difference was observed between TcRgammadeltaIEL percentages in children (6.9% +/- 0.5 of the total IELs) and adults (6.6% +/- 0.8). However, the density of CD3- IELs is significantly higher (p < 0.001) in the mucosa from controls under 3 years (50.2% +/- 2.6) than in adults (25.5% +/- 2.1). IEL lymphogram by flow cytometry is an easy, quick and reliable analysis performed in one of the biopsy specimens obtained during a diagnostic endoscopy, and confers specificity to the histopathological findings. IEL counts below 14% in children and 15% in adults should be considered within a normal range in the evaluation of duodenal mucosa by FCM. No differences with age were observed with respect to TcRgammadeltaIEL, while the CD3- IEL fraction was significantly higher on children under 3 years, with a trend to increase again in the elderly.

Marcadores serológicos y genéticos en el diagnóstico y seguimiento de la enfermedad celíaca

INTRODUCTION

Understanding of celiac disease has changed with the advent of serological markers (antigliadin IgA, anti-endomysial IgA and anti-transglutaminase IgA antibodies) and with the identification of major susceptibility genes (HLA-DQA1*05-DQB1*02). Reports of the efficacy of these diagnostic tests have varied, depending on the methodology used and the population investigated.

OBJECTIVES

To determine the clinical utility of genetic and serological markers in the diagnosis of celiac disease, their relationship with histological lesions and their changes during treatment, in order to establish an optimal diagnostic algorithm in our environment.

PATIENTS AND METHODS

We performed a retrospective study of 590 patients from the health area of Badajoz referred to the Immunology Laboratory for screening or follow-up of celiac disease. The results of intestinal histology, serological markers (antigliadin IgA, anti-endomysial IgA and anti-transglutaminase IgA antibodies), and genomic typing (HLA-DQA1*05-DQB1*02) were analyzed.

RESULTS

The sensitivity and specificity of serological tests were greater than 90 %, with a negative predictive value of 98-100 %. HLA-DQA1*05-DQB1*02 was detected in 97 % of celiac patients, with a very high negative predictive value (99 %). On biopsy, 95 % of the patients with some grade of intestinal lesion were positive for antigliadin and/or anti-endomysial antibodies.

CONCLUSION

To avoid missed diagnoses, the diagnostic algorithm of celiac disease should include at least two serological markers (antigliadin antibodies and anti-endomysial and/or anti-transglutaminase antibodies) and IgA quantification. Genomic typing should be carried out if one or more markers are positive or if the subject belongs to any of the risk groups. The physician should decide on the advisability of intestinal biopsy on the basis of the patient's clinical and immunological history.

Antiendomysial and antihuman recombinant tissue transglutaminase antibodies in the diagnosis of coeliac disease: a biopsy-proven European multicentre study

OBJECTIVE

To investigate the value of serum antitissue transglutaminase IgA antibodies (IgA-TTG) and IgA antiendomysial antibodies (IgA-EMA) in the diagnosis of coeliac disease in cohorts from different geographical areas in Europe. The setting allowed a further comparison between the antibody results and the conventional small-intestinal histology.

METHODS

A total of 144 cases with coeliac disease [median age 19.5 years (range 0.9-81.4)], and 127 disease controls [median age 29.2 years (range 0.5-79.0)], were recruited, on the basis of biopsy, from 13 centres in nine countries. All biopsy specimens were re-evaluated and classified blindly a second time by two investigators. IgA-TTG were determined by ELISA with human recombinant antigen and IgA-EMA by an immunofluorescence test with human umbilical cord as antigen.

RESULTS

The quality of the biopsy specimens was not acceptable in 29 (10.7%) of 271 cases and a reliable judgement could not be made, mainly due to poor orientation of the samples. The primary clinical diagnosis and the second classification of the biopsy specimens were divergent in nine cases, and one patient was initially enrolled in the wrong group. Thus, 126 coeliac patients and 106 controls, verified by biopsy, remained for final analysis. The sensitivity of IgA-TTG was 94% and IgA-EMA 89%, the specificity was 99% and 98%, respectively.

CONCLUSIONS

Serum IgA-TTG measurement is effective and at least as good as IgA-EMA in the identification of coeliac disease. Due to a high percentage of poor histological specimens, the diagnosis of coeliac disease should not depend only on biopsy, but in addition the clinical picture and serology should be considered.

Proximal small-bowel mucosal villous intraepithelial lymphocytes

Small-bowel biopsies are routinely obtained from adult patients as a screening tool to evaluate the possibility of gluten sensitivity (GS). Previous morphological criteria of GS including completely flattened villi are usually absent. In the context of screening for GS, an altered distribution density pattern of villous intraepithelial lymphocytes (IELs) is probably the most sensitive morphological feature to suggest the possibility of GS and prompt the initiation of further medical evaluation. Altered villous IEL density distribution is a more sensitive screening feature than villous IEL counts. With increased small-bowel GS screening biopsies, occasional adults without GS with complete villous flattening and numerous villous IELs are encountered. These patients are usually incorrectly diagnosed with GS. However, they do not respond to a gluten-free diet and slowly improve over months.

Intraepithelial lymphocytes in celiac disease

OBJECTIVE

The aim of this study was to investigate the value of immunohistochemical characterization of different intraepithelial lymphocytes (IELs) in the diagnostic workup of celiac disease (CD).

METHODS

The study involved 928 consecutive adult patients undergoing endoscopy undertaken on suspicion of CD or to ascertain the dietary compliance; the control group consisted of 59 adults who underwent endoscopy because of indigestion. Small bowel mucosal morphology, CD3+, alphabeta+, and gammadelta+ IELs were determined.

RESULTS

CD was detected in 138 and excluded in 545 adults. CD3+ and gammadelta+ IELs both showed a sensitivity of 93% for CD; specificity was 73% and 88%, respectively. For alphabeta+ cells, the sensitivity was 83% and specificity, 66%. The mucosal morphology recovered on a gluten-free diet and the densities of different IELs, even gammadelta+ cells, decreased. Only the density of gammadelta+ cells remained elevated compared with controls.

CONCLUSIONS

Counting of IELs is recommended in borderline cases where the histology is difficult to interpret. An increase especially in gammadelta+ cells strengthens the probability of CD. However, IELs are not invariably increased in CD.

New developments in celiac disease

Celiac disease remains a challenge to the clinician and scientist. It is clearly more prevalent than was previously suspected. Much interest is seen in identifying the genetic factors, which predispose to disease and the environmental agents that can trigger it. Genome-wide searches have identified a number of chromosomal susceptibility loci. Specific gliadin epitopes are being analyzed. New diagnostic options include the tissue transglutaminase enzyme-linked immunosorbent assay. Neurologic disease and bone disease are intriguing complications of celiac disease and are gradually being defined.