Increased prevalence of celiac disease without gastrointestinal symptoms in adults MICA 5.1 homozygous subjects from the Campania area

OBJECTIVES: Polymorphisms in the major histocompatibility complex class I chain-related gene A may influence its binding to the Natural Killer Cell Receptor G2D (NKG2D). We looked for polymorphisms in major histocompatibility complex class I chain-related gene A exon 5 and in Human Leukocyte Antigen (HLA)-DQ/DR in adult coeliac disease patients to determine whether they affected coeliac disease phenotypes. METHODS: Adult coeliac disease patients with (n=98) and without (n=93) gastrointestinal symptoms (gastrointestinal symptoms+/gastrointestinal symptoms-) and 108 control subjects from Campania (Italy) were characterized by Polymerase Chain Reaction (PCR) sequence specific oligonucleotide followed by PCR sequence specific primer assays for HLA DQ/DR, and by PCR followed by capillary electrophoresis for major histocompatibility complex class I chain-related gene A exon 5 polymorphisms. Immunoglobulin A (IgA) anti-transglutaminase antibodies were also evaluated by immunosorbent assay. RESULTS: Five different major histocompatibility complex class I chain-related gene A alleles were detected in both coeliac disease patients and control subjects. The major histocompatibility complex class I chain-related gene A 5.1 allele occurred more frequently in patients than in controls (p<0.05), and the major histocompatibility complex class I chain-related gene A 5.1/5.1 homozygous genotype increased the risk of gastrointestinal symptoms- coeliac disease (OR=2.79, 95% CI 1.15-6.79). Gastrointestinal symptoms- coeliac disease patients bearing major histocompatibility complex class I chain-related gene A 5.1/5.1 alleles showed lower anti-transglutaminase levels (18U/L) than the gastrointestinal symptoms+ coeliac disease patients (35U/L). HLA-DQ2/DQ8 genotypes did not differ between gastrointestinal symptoms+ and gastrointestinal symptoms- coeliac disease, although DQ8 tended to be more frequent in gastrointestinal symptoms- coeliac disease (11.7%) than in gastrointestinal symptoms+ coeliac disease (6%). CONCLUSIONS: Our study shows that a double dose of the major histocompatibility complex class I chain-related gene A 5.1 allele could predispose to the onset of gastrointestinal symptoms- coeliac disease. We can hypothesize that a lower level of immunological involvement in gastrointestinal symptoms- coeliac disease patients is associated with absence of gastrointestinal symptoms. This test could represent a second step in the genetic typing of high-risk subjects such as first-degree relatives of coeliac disease patients positive for the DQ2/DQ8 molecule.     

Non-transmitted maternal HLA DQ2 or DQ8 alleles and risk of Type I diabetes in offspring: the importance of foetal or post partum exposure to diabetogenic molecules

AIMS/HYPOTHESIS: Type I (insulin-dependent) diabetes mellitus results from an immune-mediated destruction of pancreatic beta cells for which HLA haplotypes DR3-DQ2 and DR4-DQ8 represent the strongest genetic risk markers. Mothers of patients with rheumatoid arthritis carry more frequently the HLA DR4-DQ8 haplotype as non-transmitted haplotype than mothers of healthy control subjects. As maternal cells have been shown to persist in their offspring up to 30 years after birth, we investigated whether the association of HLA DR3-DQ2 and DR4-DQ8 with Type I diabetes is purely a genetic effect acting through inheritance or whether it can also act as an environmental factor, for example through foetal exposure in utero to maternal circulating cells. METHODS: We analysed the non-transmitted parental HLA DQ alleles of 464 families (1367 subjects) with a Type I diabetic offspring. HLA DQ alleles were assessed using sequence-specific primers and allele-specific oligonucleotides hybridisation. A chi-square test was done to compare allele and transmission frequencies in the respective subsets of families. RESULTS: The non-transmitted HLA DR3-DQ2 and DR4-DQ8 were more frequent in mothers than in fathers of all non- DQ2/DQ8 heterozygous diabetic offspring ( p=0.0001) as well as in offspring not carrying any HLA high-risk allele ( p=0.0243). In patients with either risk allele alone, more maternal than paternal non-transmitted risk alleles complemented the constellation to DQ2/DQ8 ( p<0.0099). CONCLUSION/INTERPRETATION: HLA high risk alleles were more frequent among maternal non-inherited (but possibly exposed) alleles than among paternal non-inherited alleles. These results indicate that HLA DR-DQ is an environmental risk factor for Type I diabetes.     

Association of human leucocyte DR and DQ antigens in Crohn's disease in Asian Indians: a family study.

The pathogenesis of Crohn's disease (CD) involves an abnormal immune response to enteric bacteria in genetically susceptible individuals. There are no family studies regarding the association of CD with human leucocyte antigens (HLA) class II. In the present study, we have studied the association of HLA class II antigens in patients with CD and their first-degree relatives. Nine patients with CD and their first-degree relatives were studied. A group of 110 healthy unrelated and ethnically matched subjects were used as controls. Molecular HLA typing was done using the sequence-specific primer-based method. The transmission disequilibrium test (TDT) was used to analyze the results. A total of 65 individuals were included in the study; 52/56 first-degree relatives (92.8%) of 9 patients with CD consented to the study. The median age of patients was 40 years. When the distribution of the HLA class II antigens in patients was compared to that in controls no significant differences were observed even after applying the Yates correction. As the sample size of the population was small, the association of CD with DR and DQ alleles was further analyzed by using the TDT. Even after applying TDT, no significant association was observed. Familial aggregation of CD is uncommon in India. Crohn disease is not associated with HLA class II antigens in Indian patients. Genes of the major histocompatiblity complex are likely to contribute little to the susceptibility to Crohn disease in Indian patients.     

Coeliac disease among healthy members of multiple case coeliac disease families

BACKGROUND: The main objective of the study was to assess the frequency of undetected coeliac disease among the first-degree relatives of families with two or more previously diagnosed coeliac disease patients. The value of the serum endomysial antibody test as a single means of detecting clinically silent coeliac disease was evaluated. The correlation of endomysial and tissue transglutaminase antibodies and the correlation of endomysial antibodies to the HLA typical for coeliac disease was determined. METHODS: A total of 137 multiple-case coeliac disease families with 872 family members were recruited; 466 healthy family members were simultaneously screened for gliadin and endomysial antibodies and thereafter for tissue tranglutaminase antibodies. Antibody-positive persons were typed for HLA-DQ2 and DQ8. The diagnosis of coeliac disease was based on the typical mucosal lesion on small-bowel biopsies. RESULTS: Forty-four (9.4%) of the healthy family members were positive for endomysial and 48 (10.3%) for gliadin antibodies; 42 biopsies revealed 29 new coeliac disease patients (6.2% of healthy individuals). Endomysial antibodies detected 97% and gliadin antibodies 52% of the new cases. All 44 endomysial-antibody-positive and 35 of 48 gliadin-antibody-positive individuals were positive for DQ2. Tissue transglutaminase antibodies corresponded well with endomysial antibodies. CONCLUSIONS: Undetected coeliac disease is common even among healthy first-degree relatives of multiple case families. The findings emphasize the value of serum endomysial antibodies in the detection of clinically silent coeliac disease. Endomysial-antibody-positive individuals, unlike gliadin-antibody-positive ones, share the coeliac disease-type HLA-DQ.     

Association of primary sclerosing cholangitis,ulcerative colitis and coeliac disease in female siblings

Primary sclerosing cholangitis is a rare, cholestatic liver disease, most commonly affecting young men. The association of primary sclerosing cholangitis with other autoimmune disorders, although rare, indicates a genetic predisposition for this disease. We describe, for the first time, the association of primary sclerosing cholangitis, ulcerative colitis and coeliac disease in two sisters. Ulcerative colitis was mild and preceded liver disease in both patients. There were no symptoms of coeliac disease, and its silent form was diagnosed on the basis of serological tests. Both patients carried HLA molecules DR3 and DQ2. Although HLA DR4 was not found, there was a rapid progression of liver disease to cirrhosis and cholangiocarcinoma in one patient. The familial occurrence of primary sclerosing cholangitis, ulcerative colitis and coeliac disease supports the hypothesis of genetic predisposition for these diseases.     

HLA antigens and primary osteoarthritis of the hand

OBJECTIVE: Many studies have examined genetic factors associated with either development or severity of primary osteoarthritis (OA). Analyses of the frequencies of HLA antigens in various OA populations have yielded conflicting results; an increased frequency of HLA-A1, B8, and DR4 alleles has been suggested. We investigated the interrelationship between HLA antigens and primary OA. METHODS: We analyzed the frequency of HLA-A, B, C, DR, and DQ antigens in 95 patients (82 women, 13 men) with primary OA of the hands compared to 200 controls matched for age, sex, and ethnicity. Class I and Class II HLA antigens were evaluated using conventional serologic typing. RESULTS: No statistically significant difference in the distribution of HLA-A1 and B8 antigens was observed in patients with OA compared to controls. By contrast, HLA-B35, B40, DQ1, and CW4 antigens were overrepresented in the OA patients. Haplotype analysis showed an association of B35-DQ1, B40-DQ1, and DR2-DQ1 with increased OA risk. CONCLUSION: Our results suggest a role of the HLA system in the etiopathogenesis of primary OA of the hand.     

Spectrum of gluten-sensitive enteropathy in first-degree relatives of patients with coeliac disease: clinical relevance of lymphocytic enteritis

BACKGROUND: Limited data on a short series of patients suggest that lymphocytic enteritis (classically considered as latent coeliac disease) may produce symptoms of malabsorption, although the true prevalence of this situation is unknown. Serological markers of coeliac disease are of little diagnostic value in identifying these patients. AIMS: To evaluate the usefulness of human leucocyte antigen-DQ2 genotyping followed by duodenal biopsy for the detection of gluten-sensitive enteropathy in first-degree relatives of patients with coeliac disease and to assess the clinical relevance of lymphocytic enteritis diagnosed with this screening strategy. PATIENTS AND METHODS: 221 first-degree relatives of 82 DQ2+ patients with coeliac disease were consecutively included. Duodenal biopsy (for histological examination and tissue transglutaminase antibody assay in culture supernatant) was carried out on all DQ2+ relatives. Clinical features, biochemical parameters and bone mineral density were recorded. RESULTS: 130 relatives (58.8%) were DQ2+, showing the following histological stages: 64 (49.2%) Marsh 0; 32 (24.6%) Marsh I; 1 (0.8%) Marsh II; 13 (10.0%) Marsh III; 15.4% refused the biopsy. 49 relatives showed gluten sensitive enteropathy, 46 with histological abnormalities and 3 with Marsh 0 but positive tissue transglutaminase antibody in culture supernatant. Only 17 of 221 relatives had positive serological markers. Differences in the diagnostic yield between the proposed strategy and serology were significant (22.2% v 7.2%, p<0.001). Relatives with Marsh I and Marsh II-III were more often symptomatic (56.3% and 53.8%, respectively) than relatives with normal mucosa (21.1%; p = 0.002). Marsh I relatives had more severe abdominal pain (p = 0.006), severe distension (p = 0.047) and anaemia (p = 0.038) than those with Marsh 0. The prevalence of abnormal bone mineral density was similar in relatives with Marsh I (37%) and Marsh III (44.4%). CONCLUSIONS: The high number of symptomatic patients with lymphocytic enteritis (Marsh I) supports the need for a strategy based on human leucocyte antigen-DQ2 genotyping followed by duodenal biopsy in relatives of patients with coeliac disease and modifies the current concept that villous atrophy is required to prescribe a gluten-free diet.     

First-degree relatives are frequently affected in coeliac disease and dermatitis herpetiformis

BACKGROUND: Coeliac disease and dermatitis herpetiformis are phenotypically distinct gluten-sensitive diseases. Coeliac disease is known to cluster in families, whereas there is little evidence for dermatitis herpetiformis and for the occurrence of both diseases in the same families. METHODS: The study group comprised 380 patients with coeliac disease and 281 patients with dermatitis herpetiformis, with a total of 3158 first-degree relatives, followed up for a mean of 14 years. The patients were questioned about affected first-degree relatives. The prevalence and incidence of biopsy-proven coeliac disease and dermatitis herpetiformis in relatives were determined. RESULTS: Seventy-three (19.2%) patients with coeliac disease and 51 (18.1%) with dermatitis herpetiformis had affected first-degree relatives. The prevalence among relatives was similar for both diseases; 4.7% and 3.9% of the relatives had coeliac disease and 0.8% and 1.5% had dermatitis herpetiformis, respectively. The disease prevalence was 7% among siblings, 4.5% among parents and 3.5% among children. The annual incidence was 3/1,000 relatives, which is 15 times higher than among the general population. Coeliac disease and dermatitis herpetiformis were mixed in several multiple-case families. CONCLUSIONS: The present long-term follow-up study of coeliac disease and dermatitis herpetiformis shows that every fifth patient can have affected first-degree relatives, and that the prevalence among relatives is 5.5%. Dermatitis herpetiformis segregates also in the families of patients with coeliac disease, and vice versa, indicating the same genetic background.     

First-degree Relatives Are Frequently Affected in Coeliac Disease and Dermatitis Herpetiformis

Background: Coeliac disease and dermatitis herpetiformis are phenotypically distinct gluten-sensitive diseases. Coeliac disease is known to cluster in families, whereas there is little evidence for dermatitis herpetiformis and for the occurrence of both diseases in the same families. Methods: The study group comprised 380 patients with coeliac disease and 281 patients with dermatitis herpetiformis, with a total of 3158 first-degree relatives, followed up for a mean of 14 years. The patients were questioned about affected first-degree relatives. The prevalence and incidence of biopsy-proven coeliac disease and dermatitis herpetiformis in relatives were determined. Results: Seventy-three (19.2%) patients with coeliac disease and 51 (18.1%) with dermatitis herpetiformis had affected first-degree relatives. The prevalence among relatives was similar for both diseases; 4.7% and 3.9% of the relatives had coeliac disease and 0.8% and 1.5% had dermatitis herpetiformis, respectively. The disease prevalence was 7% among siblings, 4.5% among parents and 3.5% among children. The annual incidence was 3/1000 relatives, which is 15 times higher than among the general population. Coeliac disease and dermatitis herpetiformis were mixed in several multiple-case families. Conclusions: The present long-term follow-up study of coeliac disease and dermatitis herpetiformis shows that every fifth patient can have affected first-degree relatives, and that the prevalence among relatives is 5.5%. Dermatitis herpetiformis segregates also in the families of patients with coeliac disease, and vice versa, indicating the same genetic background.     

HLA-DQ and susceptibility to celiac disease: evidence for gender differences and parent-of-origin effects

BACKGROUND AND AIMS:  Celiac disease (CD) is twice as frequent among female than male. Despite the large number of reports on the DQ2/DQ8 association, no systematic studies have investigated a possible different role of the HLA genes in the two genders. We performed case-control and family-based analyses of DR-DQ variants in a pediatric CD cohort with the aim of comparing female to male associations and to investigate the paternal/maternal inheritance of the disease-predisposing haplotypes.
METHODS:  A total of 281 female and 156 male pediatric celiac patients, 292 nuclear families, and 551 controls were genotyped for HLA-DRB1, DQA1, and DQB1 loci. Odds ratio, parental origin of the disease-associated haplotypes, and transmission ratio distortion were valuated in-between male and female cases.
RESULTS:  DQ2/DQ8 were more frequent in female than in male patients (94% F, 85% M; P = 1.6 × 10⁻³) with a 99.1% and 90.5% calculated negative predictive value of the HLA test, respectively. Surprisingly, the majority of the 39 DQ2/DQ8 negative cases were male. The analysis of the DQ2 haplotype origin showed that 61% of female patients and 42% of male patients carried a paternal combination ( P = 0.02). The transmission disequilibrium test (TDT) proved the major distortion in the DR3-DQ2 transmission from fathers to daughters.
CONCLUSIONS:  CD is confirmed to be more prevalent in female than in male (F:M = 1.8) but, in DQ2/DQ8 negative patients, we found an unexpected male excess (F:M = 0.7). Moreover, only the inheritance of a paternal DQ2 haplotype led to a daughters predominance. These data show a role of HLA genes on the disease sex bias and suggest a possible different effect of parent-specific epigenetic modifications in the two genders.     

Prevalence,human leukocyte antigen typing and strategy for screening among Asian first‐degree relatives of children with celiac disease

Background and Aim: Data on prevalence, human leukocyte antigen (HLA) typing and small bowel histology among first‐degree relatives of subjects with celiac disease (CD) is scarce. This prospective study evaluated the prevalence and role of HLA DQ2/8 testing in screening of first‐degree relatives of children with CD. Methods: Thirty confirmed children with CD and 91/94 first‐degree relatives (parents and siblings) were enrolled. HLA DQ2/8 testing was carried out in all index CD cases. Clinical evaluation with a questionnaire, total serum immunoglobulin A (IgA), human IgA‐tissue transglutaminase (IgA‐tTGA) and HLA DQ2/8 testing was carried out in all first‐degree relatives. Subjects who were positive for IgA‐tTGA were recommended endoscopic duodenal biopsy to document histological changes of CD. Results: Nine first‐degree relatives were positive for IgA‐tTGA, seven underwent duodenal biopsy and four subjects had Marsh IIIa changes suggestive of CD. The prevalence of histologically confirmed CD in first‐degree relatives was 4.4%. The prevalence of potential CD was 9.8%. IgA‐tTGA‐positive subjects (4/9) were significantly more often symptomatic than IgA‐tTGA‐negative first‐degree relatives (2/82). Twenty‐nine (96.6%) index cases of CD and all IgA‐tTGA‐positive first‐degree relatives were positive for HLA DQ2. None of the index CD cases or first‐degree relatives were HLA DQ8‐positive. A total of 85% of the first‐degree relatives were positive for HLA DQ2 and thus at risk of developing CD. Conclusions: In this first Asian study on a limited number of families of children with CD, 4.4% of the first‐degree relatives had CD. Only 15% of the first‐degree relatives were negative for HLA DQ2/DQ8. Initial evaluation with HLA and serology followed by only serial serology in HLA‐positive relatives is recommended.     

HLA-DR and -DQ phenotypes in inflammatory bowel disease: a meta-analysis.

BACKGROUND: Susceptibility to inflammatory bowel disease (IBD) is partially genetically determined and the HLA class II genes are candidates for a role in genetic susceptibility to IBD, because their products play a central role in the immune response. Multiple studies have reported associations between HLA-DR or -DQ phenotypes and either ulcerative colitis or Crohn's disease, but much of the data are still controversial. AIMS: To estimate overall associations between HLA class II phenotypes and IBD, and to establish the relative risk conferred by HLA-DR and -DQ phenotypes by meta-analysis. METHODS: Medline was searched for publications reporting on the relation between IBD and HLA class II phenotypes. Raw data were extracted by recalculating the number of phenotypes or the number of alleles of the main antigens. Odds ratios and confidence intervals were calculated according to the Mantel-Haenszel method. RESULTS: DR2, DR9, and DRB1*0103 were positively associated with ulcerative colitis, and a negative association was found for DR4 and ulcerative colitis. For Crohn's disease a positive association was found with DR7, DRB3*0301, and DQ4 and a negative association with DR2 and DR3. CONCLUSIONS: Both ulcerative colitis and Crohn's disease are associated with specific HLA class II phenotypes. Further analysis of these phenotypes and subgroup analysis may elucidate how these alleles contribute to susceptibility to IBD.     

Extreme genetic risk for type 1A diabetes

Type 1A diabetes (T1D) is an autoimmune disorder the risk of which is increased by specific HLA DR/DQ alleles [e.g., DRB1*03-DQB1*0201 (DR3) or DRB1*04-DQB1*0302 (DR4)]. The genotype associated with the highest risk for T1D is the DR3/4-DQ8 (DQ8 is DQA1*0301, DQB1*0302) heterozygous genotype. We determined HLA-DR and -DQ genotypes at birth and analyzed DR3/4-DQ8 siblings of patients with T1D for identical-by-descent HLA haplotype sharing (the number of haplotypes inherited in common between siblings). The children were clinically followed with prospective measurement of anti-islet autoimmunity and for progression to T1D. Risk for islet autoimmunity dramatically increased in DR3/4-DQ8 siblings who shared both HLA haplotypes with their diabetic proband sibling (63% by age 7, and 85% by age 15) compared with siblings who did not share both HLA haplotypes with their diabetic proband sibling (20% by age 15, P < 0.01). 55% sharing both HLA haplotypes developed diabetes by age 12 versus 5% sharing zero or one haplotype (P = 0.03). Despite sharing both HLA haplotypes with their proband, siblings without the HLA DR3/4-DQ8 genotype had only a 25% risk for T1D by age 12. The risk for T1D in the DR3/4-DQ8 siblings sharing both HLA haplotypes with their proband is remarkable for a complex genetic disorder and provides evidence that T1D is inherited with HLA-DR/DQ alleles and additional MHC-linked genes both determining major risk. A subset of siblings at extremely high risk for T1D can now be identified at birth for trials to prevent islet autoimmunity.     

Juvenile idiopathic arthritis (JIA) is primarily associated with HLA-DR8 but not DQ4 on the DR8-DQ4 haplotype

BACKGROUND: Juvenile idiopathic arthritis (JIA) is strongly associated with the DR8-DQ4 haplotype. The genes encoding DR8 and DQ4 are in strong linkage disequilibrium (LD) and occur together on the same HLA haplotype in almost all patients and controls. Because of the strong LD it is not clear whether DR8, DQ4, or both, are primarily associated with JIA. OBJECTIVE: To unveil the primary association of JIA--that is, with DR8 or DQ4. METHODS: DRB1, DQA1, and DQB1 alleles of 585 Norwegian and 47 Polish unrelated patients with JIA (categorised as pauciarticular and rheumatoid factor negative polyarticular JIA), and of 3155 Norwegian and 158 Polish unrelated controls, were typed using a polymerase chain reaction or oligonucleotide hybridisation and sequence-specific primers method. RESULTS: Several haplotypes which encoded DR8 (that is, carried DRB1*08) and which did not encode DQ4 (that is, did not carry DQA1*0401) were found. Such haplotypes were found in three Norwegian patients and two controls (p=0.029). In the Polish population such haplotypes were found among four patients with JIA and two controls (p=0.025). No haplotypes which carried DQA1*0401 and DQB1*0402 in the absence of DRB1*08 were found, either among patients with JIA (Polish and Norwegian) or among the controls (Polish). CONCLUSION: On the DR8-DQ4 haplotype the DRB1*08 allele is primarily associated with JIA.     

HLA antigens and atopy in children with coeliac disease

HLA antigens and various aspects of atopy were studied in 42 Finnish children and adolescents with coeliac disease, and the results were compared with findings of recent population studies. The HLA associations were as expected: relative risks for coeliac disease in individuals with HLA-B8, DR3, and DR7 were 8 . 0, 18 . 6, and 15 . 0, respectively. Children with coeliac disease were significantly more often atopic than unselected schoolchildren. Atopy was significantly more frequent and the onset of coeliac disease later for B8/DR3- patients than B8/DR3+ patients. There was no obvious relation between DR7 and atopy. It is concluded that atopy predisposes to coeliac disease partly independently of the HLA-DR3 associated disease susceptibility gene(s), and that different mechanisms may operate in the pathogenesis in coeliac disease patients with and without atopy.     

HLA association with dermatitis herpetiformis is accounted for by a cis or transassociated DQ heterodimer.

HLA-DR, DQ, and DP restriction fragment genotyping was undertaken in 23 dermatitis herpetiformis patients and 53 healthy control subjects. HLA-DQw2 was present in 100% of patients with dermatitis herpetiformis (23 of 23) versus 40% of control subjects (21 of 53). Significant secondary associations occurred with HLA-DR3 (91% of patients versus 28% of control subjects) and DPw1 (39% of patients versus 11% of control subjects). Dermatitis herpetiformis and coeliac disease thus share an identical HLA class II association. It is likely that HLA class II genes directly influence the immune responses leading to mucosal damage in both diseases. The strongest candidate for disease susceptibility to dermatitis herpetiformis is DQw2. The HLA molecule most likely to be involved in coeliac disease is a specific DQ alpha/DQ beta heterodimer, encoded in cis arrangement in DR3 haplotypes or in trans arrangement in a DR5, 7 genotype. Our data on dermatitis herpetiformis patients fits this model perfectly. All these patients are capable of expressing this molecule, which may be responsible for the gluten sensitive enteropathy seen in a subgroup of patients with dermatitis herpetiformis and coeliac disease.     

Prevalence of coeliac disease in patients with sarcoidosis

OBJECTIVE: Susceptibility to sarcoidosis and coeliac disease has been linked to the class II haplotype HLA-DR3, DQ2, and an association between the two disorders has been suggested. As a pilot study, we have sought to determine the prevalence of coeliac disease in a cohort of Irish patients with sarcoidosis. DESIGN: Prospective, case-controlled study. METHODS: One hundred and two sarcoid patients (47 males, 55 females) from the west of Ireland and 105 (52 males, 53 females) healthy, ethnically matched, controls underwent interview and screening for coeliac disease and human leucocyte antigen typing by serology. Those with elevated anti-gliadin IgA (AGA) and/or positive endomysial antibody (EMA) were offered small intestinal biopsy. RESULTS: Three (3%) sarcoid patients had a prior diagnosis of coeliac disease. A further 12 (12%) patients and four (4%) controls had elevated AGA (P = 0.047), of whom three and one, respectively, had positive EMA. Small intestinal biopsy in 11 patients and three controls confirmed coeliac disease in one individual each, giving a prevalence of coeliac disease in patients compared with controls of 4/102 (4%) versus 1/105 (1%) (P = 0.21). Sensitivity and specificity of EMA and elevated AGA in sarcoid patients was 100% and 50%, and 50% and 9%, respectively. Of the four affected sarcoid patients, three carried HLA-DR3, DQ2 and one carried DR5 (12), DR7, DQ2. CONCLUSION: We have demonstrated a moderately increased prevalence of coeliac disease in Irish patients with sarcoidosis, which we feel justifies future screening of our sarcoid population. Estimation of EMA is recommended and should be restricted to those with susceptible haplotypes.     

HLA-DQ typing in the diagnosis of celiac disease

OBJECTIVE: More than 95% of celiac patients share the major histocompatibility complex II class human leukocyte antigen (HLA) DQ2 or DQ8 haplotype; patients negative for both types are unlikely to suffer from celiac disease. Our aim was to investigate whether HLA-DQ2 and -DQ8 typing is helpful when diagnosis is uncertain because of the absence of unequivocal small bowel villous atrophy. METHODS: HLA-DQ2 and -DQ8 typing was carried out in 59 patients evincing nondiagnostic small bowel mucosal lesion or positive celiac serology, and in 17 patients maintaining a gluten-free diet without biopsy-proven celiac disease. HLA findings were compared to small bowel mucosal morphology; intraepithelial lymphocytes; and serum endomysial (EmA), reticulin, tissue transglutaminase (anti-tTG) and gliadin antibodies. RESULTS: Of the 59 patients evincing only minor small bowel mucosal changes or positive celiac disease serology, 22 (37%) were negative for DQ2 and DQ8. All EmA-positive patients had celiac-type HLA, but antireticulin antibody, anti-tTg, and antigliadin antibody were also present in HLA-DQ2- and -DQ8-negative individuals. Eleven of 17 patients (65%) observing a gluten-free diet before small bowel biopsy did not share celiac-type HLA. None of the 17 had apparent villous atrophy. Serum EmA and anti-tTG were negative in all. HLA-DQ typing is less expensive than follow-up biopsy in the exclusion of celiac disease. CONCLUSIONS: HLA-DQ2 and -DQ8 determination is useful in exclusion, probably lifelong, of celiac disease in individuals with an equivocal small bowel histological finding. The low specificity of this test must, however, be borne in mind.     

Genetic association of autoimmune hepatitis and human leucocyte antigen in German patients

INTRODUCTION Autoimmune hepatitis (AIH) is characterized by portal lymphatic infiltrates on liver histology and in most patients with the occurrence of autoantibodies such as antinuclear, smooth muscle antibody-positive (ANA/ SMA, type 1), liver-kidney microsomal antibody-positive (LKM-1), and soluble liver antigen/liver-pancreas antigen (SLA/LP) antibodies. Untreated, the disease usually runs an unfavorable course with 5 year survival rates of 50% and 10 year survival rates between…     

Not all HLA DR3 DQ2 haplotypes confer equal susceptibility to coeliac disease: transmission analysis in families

BACKGROUND: HLA-DQ is the only established susceptibility factor for coeliac disease. We tested whether all HLA haplotypes with the known risk marker, HLA-DQ2, confer equal susceptibility to coeliac disease, i.e. whether haplotype transmission from DQ2 homozygous parents to patients is random. The random transmission would strengthen the importance of DQ2 as the only risk factor within the HLA region. METHODS: Inheritance of DQ2-positive haplotypes from parent to patients was investigated in 14 of 127 Finnish coeliac families who had an HLA-DQ2 homozygous parent. HLA alleles and 18 HLA-linked microsatellite markers were used to determine the haplotypes, which were divided into those transmitted and those non-transmitted from DQ2-homozygous parents to patients: RESULTS: Transmitted haplotypes differed clearly from those not transmitted. The alleles in the transmitted haplotypes were strongly conserved and predominantly consisted of the well-known HLA-A*01, B*08, DRB1*03, DQ2, DPB1*0101 haplotype. The non-transmitted haplotypes, on the other hand, were significantly more heterogeneous; in particular, markers near HLA-A and -B genes differed from the transmitted haplotypes. CONCLUSIONS: The results suggest that DQ2 is not the only HLA-linked genetic risk factor for coeliac disease but the conserved haplotype harbours at least one other risk gene.