title: The role of HLA DQ2 and DQ8 in dissecting celiac-like disease in common variable immunodeficiency.
abstract: OBJECTIVE
  Gastrointestinal manifestations are frequent in patients with common variable immunodeficiency (CVID), and some of the patients present with celiac-like features. Diagnosing celiac disease (CD) in CVID however is challenging, as autoantibody detection and histopathology of the small intestine cannot reliably discriminate between classic CD and a celiac-like disease in these individuals. For the development of classic gluten-sensitive CD a certain HLA haplotype involving the loci DQA1* and DQB1* and encoding two different HLA DQ heterodimers is the prerequisite. We aimed to determine the frequency of these haplotypes in CVID patients with suspected CD. Furthermore, we report on autoimmune manifestations and the lymphocyte phenotype in these patients.
  
  
  METHODS
  By retrospective analysis data on gastrointestinal symptoms, diet, concurrent autoimmune diseases, and routine laboratory values were collected. CVID patients were classified according to their B-cell phenotype. Expression of HLA-DQA1* and HLA-DQB1* alleles were determined by genetic analysis.
  
  
  RESULTS
  Twenty out of 250 CVID patients presented with a clinical phenotype resembling celiac disease. Four (20%) out of these CVID patients carried the CD-associated HLA DQ2.5 or DQ8 heterodimer, while HLA DQ2.5 was present in 100% of a CD control cohort. Gluten-free diet (GFD) resulted in a clinical and histological response in two out of four patients with HLA high-risk alleles for CD. The response could not be assessed in the remaining two patients, as these patients did not adhere sufficiently long to GFD. The percentage of autoimmune manifestations other than CD was high (50%) in CVID patients presenting with a CD-like enteropathy, and most of these patients had an expansion of B-cells with low expression of CD21 (CD21low B-cells).
  
  
  CONCLUSIONS
  In CVID patients with suspected celiac disease typing of the HLA loci DQA1 and DQB1 can help to identify those that have a genetic susceptibility for CD. In CVID patients with a celiac-like phenotype but negative for CD-associated HLA-DQ markers, an autoimmune enteropathy (AIE) as part of an extended autoimmune dysregulation needs to be considered. This has important implications for further diagnostics and therapy of these patients.
authors.affiliation: Department of Rheumatology and Clinical Immunology, University Medical Center Freiburg, Freiburg, Germany. nils.venhoff@uniklinik-freiburg.de
authors.forename: Nils
authors.initials: N
authors.lastname: Venhoff
authors.forename: Florian
authors.initials: F
authors.lastname: Emmerich
authors.forename: Michaela
authors.initials: M
authors.lastname: Neagu
authors.forename: Ulrich
authors.initials: U
authors.lastname: Salzer
authors.forename: Corinna
authors.initials: C
authors.lastname: Koehn
authors.forename: Sibyll
authors.initials: S
authors.lastname: Driever
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kreisel
authors.forename: Marta
authors.initials: M
authors.lastname: Rizzi
authors.forename: Nora M
authors.initials: NM
authors.lastname: Effelsberg
authors.forename: Florian
authors.initials: F
authors.lastname: Kollert
authors.forename: Sigune
authors.initials: S
authors.lastname: Goldacker
authors.forename: Reinhard E
authors.initials: RE
authors.lastname: Voll
authors.forename: Klaus
authors.initials: K
authors.lastname: Warnatz
authors.forename: Jens
authors.initials: J
authors.lastname: Thiel
mesh_terms: D000328:Adult; D000483:Alleles; D001327:Autoimmune Diseases / Q000235:genetics / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D002446:Celiac Disease / Q000235:genetics* / Q000276:immunology; D017074:Common Variable Immunodeficiency / Q000235:genetics* / Q000276:immunology; D055050:Diet, Gluten-Free; D005260:Female; D005787:Gene Frequency; D005820:Genetic Testing / Q000379:methods; D006683:HLA-DQ Antigens / Q000235:genetics* / Q000276:immunology; D059848:HLA-DQ alpha-Chains / Q000235:genetics / Q000276:immunology; D059866:HLA-DQ beta-Chains / Q000235:genetics / Q000276:immunology; D006801:Humans; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D017464:Receptors, Complement 3d / Q000235:genetics / Q000276:immunology; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C053186:HLA-DQ2 antigen; C109756:HLA-DQ8 antigen; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen; D017464:Receptors, Complement 3d