title: IgG anti-IgA antibodies in paediatric antibody-deficient patients receiving intravenous immunoglobulin.
abstract: BACKGROUND
  Immunoglobulin replacement therapy is an effective route of management for both infections and non-infectious complications in predominantly antibody deficiency (PAD). Trace levels of IgA (ranged from 0.4 to 2500 mg/ml), which exist in all immunoglobulin products, could lead to an increased susceptibility for adverse reactions in PAD patients. Furthermore, the exact mechanism which stimulates the anti-IgA antibody production in PAD is still unknown. The aim of this study was to evaluate IgG anti-IgA antibodies in PAD patients receiving intravenous immunoglobulin (IVIg) and its predisposing factors.
  
  
  METHODS
  Available patients with confirmed diagnosis of PAD, who underwent regular IVIg replacement therapy in our centre, were enrolled in the study. Control group included 24 healthy individuals as the negative control and eight symptomatic patients with IgA deficiency as the positive control groups. IgG anti-IgA antibodies level was measured by the ELISA method.
  
  
  RESULTS
  A significant difference was observed between Anti-IgA level of common variable immunodeficiency (CVID) and other PAD groups (p=0.02). Moreover, six CVID patients were seropositive for the IgG anti-IgA antibody, with higher susceptibility to the adverse reactions (p<0.001). IgG anti-IgA level has a negative relationship with serum IgA level (r=-0.06) and IVIg treatment duration (r=-0.006).
  
  
  CONCLUSIONS
  Our data suggested that there was a significant association between anti-IgA antibody presence and the adverse reactions, especially in CVID patients with higher susceptibility to produce this constitutional antibody.
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Torabi Sagvand
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Mirminachi
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran; Division of Clinical Immunology, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Abolhassani
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.
authors.forename: T
authors.initials: T
authors.lastname: Shokouhfar
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.
authors.forename: T
authors.initials: T
authors.lastname: Keihanian
authors.affiliation: Noor Pathobiology Laboratory, Tehran, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Amirzargar
authors.affiliation: Pediatric Respiratory Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Mahdaviani
authors.affiliation: Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran. Electronic address: aghamohammadi@sina.tums.ac.ir.
authors.forename: A
authors.initials: A
authors.lastname: Aghamohammadi
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000097:blood* / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016756:Immunoglobulins, Intravenous / Q000009:adverse effects*; D007153:Immunologic Deficiency Syndromes / Q000188:drug therapy*; D008297:Male
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous; C049937:anti-IgA
keywords: Adverse reaction; Anti-IgA; Common variable immunodeficiency; Intravenous immunoglobulin