A novel method to standardise serum IgA measurements shows an increased prevalence of IgA deficiency in young children with recurrent respiratory tract infections

Clinical & Translational Immunology

Marianne Boes¹  Mischa H Koenen¹  Thijs C vanHolten²  Madeleen Bosma²  Fabiënne MY Wopereis³  Anja Roos⁴  Lilly M Verhagen⁵  Joris M vanMontfrans⁵  Elisabeth AM Sanders⁵  Debby Bogaert⁵  Jojanneke Heidema⁶  Walter AF Balemans⁶  Erhard vander Vries⁷  Udo A Roorda⁸ 

[1] Center of Translational Immunology University Medical Center Utrecht Utrecht The Netherlands;Department of Clinical Chemistry St Antonius Hospital Nieuwegein The Netherlands;Department of General Practice University Medical Center Utrecht Utrecht The Netherlands;Department of Medical Microbiology and Immunology St Antonius Hospital Nieuwegein The Netherlands;Department of Pediatric Infectious Diseases and Immunology Wilhelmina Children's Hospital, University Medical Center Utrecht Utrecht The Netherlands;Department of Pediatrics St Antonius Hospital Nieuwegein The Netherlands;Department of Research & Development GD Animal Health Deventer The Netherlands;Department of Research Data Management Pediatrics, Woman & Baby UMC Utrecht Utrecht The Netherlands;

关键词: case–control study;    IgA deficiency;    immunoglobulin A;    reference values;    respiratory tract infections;   

DOI  :  10.1002/cti2.1344

来源: DOAJ

【 摘 要 】

Abstract Objectives While physicians are often confronted with immunoglobulin A (IgA) deficiency in children with recurrent infections, the clinical relevance of this finding is unclear. Large‐scale studies examining the significance of IgA deficiency in children are hampered by differences in techniques for measuring IgA and the physiological increase of IgA with age. Both result in a variety of reference values used for diagnosing IgA deficiency. We propose a new laboratory‐independent method to accurately compare IgA measurements in children of varying ages. Methods We present a method to standardise IgA values for age and laboratory differences. We applied this method to a multicentre case–control study of children under the age of seven suffering from recurrent respiratory tract infections (rRTI, cases) and children who had IgA measured as part of coeliac disease screening (controls). We defined IgA deficiency as serum IgA measurements < 2.5% for age‐specific reference values. Results We developed reference values for IgA for seven age groups and five different laboratory assays. Using these reference values, IgA measurements from 417 cases and 224 controls were standardised to compare groups. In children aged 2 years and older, IgA deficiency was observed in 2.9% (7/242) of cases and 0% (0/189) of controls (P = 0.02). Conclusion We present a method to compare IgA values in cohorts that vary in age and laboratory assay. This way, we showed that IgA deficiency was more prevalent in children with rRTI compared with controls. This implicates that IgA deficiency may be a clinically relevant condition, even in young children.

【 授权许可】

Unknown