A Survey Of Immunoglobulin A Deficiency In Shanghai Blood Donors And Identification Of CD36 Deficiency Phenotype

Immunoglobulin A (IgA) deficiency (IgAD) is commonly defined as a serum IgA level of< 5 mg/dL, and a concentration of< 0.05 mg/dL is defined as absolute IgA deficiency. Individuals with absolute IgA deficiency may develop specific antibodies against IgA (anti-IgA), which can increase the risk of severe transfusion reaction to normal IgA-containing blood components. Severe symptoms presents shock or/and even death. The frequence of IgAD has been broadly studied and varied in different ethic groups. Up to now, the frequency remains unknown in Chinese blood donors, as well as lacking strategy of safe blood transfusion to IgA-deficient patients. To improve safe blood transfusion, we investigated the incidence of IgAD among blood donor population in Shanghai region and simply evalutate the risk of transfusion reaction caused by anti-IgA. An in-house sandwich enzyme-linked immunosorbent assay was initially performed to detect the serum concentration of IgA from 22 609 blood donors. And the method of particle immunoassay was used for confirmation. Anti-IgA were further detected in IgA-deficient blood samples. Of the total 22 609 healthy blood donors screened,14 were observed as having IgA deficiency and of which 7 cases were comfirmed as having absolute IgA deficiency (< 0.05 mg/dL). Hence, the frequency of IgA deficiency and absolute IgA deficiency in Shanghai blood donor population is 0.062%(1:1615) and 0.031%(1:3230), respectively. The mean level of IgA concentrations for remaining 7 cases ranged from 0.39 to 3.70 mg/dL. Anti-IgA were identified in 2 of the 14 IgA-deficient blood donors whose IgA levels were<5 mg/dL. The incidence of IgA deficient indivudiuals with anti-IgA was 0.009%(1:11 305). The frequency of IgAD in Shanghai healthy blood donors is higher than that in Japanese but lower than Caucasians. However, potential risks exist in performing blood transfusion to IgA-deficient persons, and measures should be taken to reduce IgA anaphylaxis.