title: Optimal strategies to identify aberrant intra-epithelial lymphocytes in refractory coeliac disease.
abstract: BACKGROUND
  Different strategies have been developed to identify those refractory celiac disease (RCD) patients who are at risk to develop an enteropathy associated T-cell lymphoma (EATL). Flow cytometric analysis of intra-epithelial lymphocytes (IEL) with an aberrant phenotype is considered the golden standard but is not widely available. Immunohistochemistry (IHC) and T-cell receptor (TCR) rearrangement studies are commonly available but may lack sensitivity and specificity. Here, we compared the three different methods in the workup of patients suspected for RCD.
  
  
  METHODS
  Duodenal biopsies from control patient (n = 5), RCD patients with moderately increased aberrant IEL populations (20-50 %: n = 14), and RCD patients with high numbers of aberrant IEL (>50 %: n = 5) as determined by flow cytometry were analysed by IHC and TCR-γ chain rearrangement analysis. Three pathologists scored the slides independently.
  
  
  RESULTS
  Sensitivity of IHC and TCR-γ rearrangement analysis in RCD patients with high numbers of aberrant IELs was 100 and 71 %, respectively. RCD patients with aberrant cells between 25 and 50 % however, were missed by IHC and TCR in 50 and 57 % of cases, respectively. In addition, inter-rater reliability analysis of the IHC scoring revealed coder-pair Kappa coefficients between 0.28 and 0.85.
  
  
  CONCLUSIONS
  Immunohistochemistry and to a lesser extent TCR-γ clonality analysis are sensitive in identifying patients with high numbers of aberrant IEL populations, yet miss half of RCD patients with moderately increased numbers. In addition, IHC has a high inter-observer variability. Therefore, patients suspected for RCD should undergo flow cytometric analysis of the duodenum.
authors: Department of Gastroenterology and Hepatology, VU University Medical Center, PO Box 7057, 1007 MB, Amsterdam, The Netherlands, rl.vanwanrooij@vumc.nl.
authors: R L J
authors: RL
authors: van Wanrooij
authors: D M J
authors: DM
authors: Müller
authors: E A
authors: EA
authors: Neefjes-Borst
authors: J
authors: J
authors: Meijer
authors: L G
authors: LG
authors: Koudstaal
authors: D A M
authors: DA
authors: Heideman
authors: H J
authors: HJ
authors: Bontkes
authors: B M E
authors: BM
authors: von Blomberg
authors: G
authors: G
authors: Bouma
authors: C J J
authors: CJ
authors: Mulder
mesh_terms: D000328:Adult; D000368:Aged; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002446:Celiac Disease / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D002469:Cell Separation / Q000379:methods; D004351:Drug Resistance; D005260:Female; D005434:Flow Cytometry; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000276:immunology* / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D012008:Recurrence; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D011948:Receptors, Antigen, T-Cell