title: Diagnosing celiac disease in patients with a history of lymphoma: factors that matter.
abstract: OBJECTIVE
  The aim of this study was to identify pitfalls in establishing the diagnosis of celiac disease (CD) in patients with a history of lymphoma.
  
  
  METHODS
  A total of 103 patients with a history of lymphoma had anti-tissue transglutaminase antibodies (atTGA) and their class A, G, and M immunoglobulin (IgA, IgG) levels determined. Patients with atTGA positivity underwent enterobiopsy and CD-associated HLA locus testing.
  
  
  RESULTS
  The mean age of patients was 55 ( ± 13.5) years. The predominant lymphoma types included B-type non-Hodgkin's lymphoma (B-NHL, 66 %), T-type NHL (8 %), and Hodgkin's lymphoma (26 %). Serological positivity was documented in 3.9 % of cases; one patient had the diagnosis of CD confirmed by enterobiopsy. In 11 patients (10.7 %), IgA levels were decreased to a various extent; of these patients, 10 were shown to have also their IgG levels decreased. The median time from follow-up to blood collection was 58 (32-104) months. The decrease in immunoglobulin levels correlated with a more advanced stage of the tumor (Ann Arbor III-IV) at the time of diagnosis [1.4 (0.9-2.0) g/l versus 2.4 (1.5-3.0) g/l for IgA, p = 0.0001; and 9.4 (7.2-11.5) g/l versus 11.2 (10.3-12.3) g/l for IgG, p = 0.001] and older age [65 (54-72) years versus 55 (44-61) years for IgA, p = 0.04; and 69 (59-74) years versus 53 (43-61) years for IgG, p = 0.0001]. Rituximab therapy in B-NHL patients had no effect on the subsequent incidence of decreased IgA levels.
  
  
  CONCLUSIONS
  Reduced IgA and IgG levels represent important factors contributing to the low detection rate of serological screening for CD in patients with a history of lymphoma.
authors.affiliation: Ist Medical Department, Division of Gastroenterology and Hepatology, Charles University Medical Faculty and Teaching Hospital, Alej Svobody 80, 30460, Pilsen, Czech Republic, balihar@fnplzen.cz.
authors.forename: Karel
authors.initials: K
authors.lastname: Balihar
authors.forename: Jana
authors.initials: J
authors.lastname: Kozeluhova
authors.forename: Vaclav
authors.initials: V
authors.lastname: Hejda
authors.forename: Michal
authors.initials: M
authors.lastname: Krcma
authors.forename: Daniel
authors.initials: D
authors.lastname: Lysak
authors.forename: Jitka
authors.initials: J
authors.lastname: Gorcikova
authors.forename: Ondrej
authors.initials: O
authors.lastname: Hes
authors.forename: Martin
authors.initials: M
authors.lastname: Matejovic
mesh_terms: D015415:Biomarkers / Q000097:blood; D002446:Celiac Disease / Q000097:blood* / Q000175:diagnosis* / Q000453:epidemiology; D015897:Comorbidity; D018153:Czech Republic / Q000453:epidemiology; D003951:Diagnostic Errors / Q000517:prevention & control / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood*; D015994:Incidence; D008223:Lymphoma / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D007070:Immunoglobulin A; D007074:Immunoglobulin G