title: Prevalence of immunoglobulin A deficiency in Chinese blood donors and evaluation of anaphylactic transfusion reaction risk.
abstract: OBJECTIVE
  We investigated the incidence of immunoglobulin A (IgA) deficiency in Chinese population.
  
  
  BACKGROUND
  The frequency of IgA deficiency, defined as a serum IgA level of <0.05 mg dL(-1) , has been broadly studied in different ethnic groups. Individuals with IgA deficiency may form specific antibodies against IgA, which can cause an anaphylactic response when the patient receives an IgA-containing blood transfusion.
  
  
  METHODS
  A sandwich enzyme-linked immunosorbent assay was performed to screen for IgA deficiency and particle gel immunoassay used for confirmation. IgA antibodies were further detected by the DiaMed anti-IgA test in IgA-deficient blood donors.
  
  
  RESULTS
  Of the total 22,609 healthy blood donors screened, only seven cases were confirmed as having IgA deficiency (<0.05 mg dL(-1) ). Another seven cases displayed relative IgA deficiencies, with mean IgA concentrations ranging from 0.39 to 3.70 mg dL(-1) . Anti-IgA was identified in 2 of the 14 IgA-deficient blood donors whose IgA levels were <5 mg dL(-1) . Estimation of the theoretical risk for IgA anaphylactic transfusion reaction was 0.009%.
  
  
  CONCLUSIONS
  The prevalence of IgA deficiency in Chinese is low. However, potential risks exist in performing blood transfusion to IgA-deficient persons, and measures should be taken to reduce IgA anaphylaxis.
authors.affiliation: Shanghai Institute of Blood Transfusion, Shanghai Blood Center, China.
authors.forename: M L
authors.initials: ML
authors.lastname: Feng
authors.forename: Y L
authors.initials: YL
authors.lastname: Zhao
authors.forename: T
authors.initials: T
authors.lastname: Shen
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.forename: B
authors.initials: B
authors.lastname: Yin
authors.forename: R Z
authors.initials: RZ
authors.lastname: Liu
authors.forename: K C
authors.initials: KC
authors.lastname: Qian
authors.forename: D-Z
authors.initials: DZ
authors.lastname: Liu
mesh_terms: D000707:Anaphylaxis / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D044466:Asian People; D001782:Blood Donors; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D017098:IgA Deficiency / Q000175:diagnosis* / Q000453:epidemiology* / Q000276:immunology; D007518:Isoantibodies / Q000097:blood; D008403:Mass Screening; D015995:Prevalence; D065227:Transfusion Reaction
chemical_list: D007518:Isoantibodies