Immunoglobulin interference in serum follicle-stimulating hormone assays: autoimmune and heterophilic antibody interference.
Interference in immunoassay caused by endogenous immunoglobulin is a cause of incorrect laboratory results that can drastically affect patient management. Two cases of immunoglobulin interference in serum follicle-stimulating hormone (FSH) assays are presented. These cases illustrate two common mechanisms for false-positive interference in two-site (sandwich) immunoassays. The first case describes a circulating autoimmune FSH immunoglobulin complex ('macro'-FSH), which has not been previously described for FSH, and the second a cross-linking antibody directed against the assay reagents. Immunoglobulin interference was detected and characterized using a combination of method comparison, immunosubtraction and size exclusion chromatography.
Department of Clinical Biochemistry, Birmingham Children's Hospital, Steelhouse Lane, Birmingham, UK.
Rachel
R
Webster
Michael
M
Fahie-Wilson
Peter
P
Barker
V Krishna
VK
Chatterjee
David J
DJ
Halsall
D000293:Adolescent; D000910:Antibodies, Heterophile / Q000276:immunology*; D016477:Artifacts; D015551:Autoimmunity / Q000276:immunology*; D001774:Blood Chemical Analysis / Q000379:methods*; D005189:False Positive Reactions; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood* / Q000276:immunology; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D055815:Young Adult
D000910:Antibodies, Heterophile; D005640:Follicle Stimulating Hormone