Long-term persistence of selective IgA deficiency in healthy adults.
A follow-up study of 204 healthy blood donors with IgA deficiency, identified between 1971 and 1980, was carried out. Sera were initially screened by a double diffusion method and 182 were retested by a more sensitive haemagglutination inhibition method. A reexamination was performed in 1990 and, again, in 1991-1992 using an enzyme immunoassay (EIA) developed for the measurement of very low concentrations of IgA. The median follow-up period was 19 years, and in 159 (78%) subjects no serum IgA could be detected in any of the measurements. In 42 (21%) subjects, serum IgA was detectable (> 0.18 mg/L), but the level was below the lower limit of the reference range for adults (800 mg/L) and remained relatively constant. Three subjects showed minute amounts of IgA by EIA (0.2-3 mg/L) in one of the follow-up samples in 1990-1992, but the level was below the detection limit of the EIA (0.05 mg/L) in the other sample. Thus, not only does primary IgA deficiency appear to be permanent, but also lower than normal serum IgA levels remain the same in healthy adults.
Koskinen
S
S
Finnish Red Cross Blood Transfusion Service, Helsinki.
Tölö
H
H
Hirvonen
M
M
Koistinen
J
J
D000293:Adolescent; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017098:IgA Deficiency / Q000276:immunology*; D007070:Immunoglobulin A / Q000097:blood; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged
D007070:Immunoglobulin A