Biochemia Medica, Vol. 19 No. 1, 2009.
Review article
Interferences in quantitative immunochemical methods
Slavica Dodig
orcid.org/0000-0002-3419-5171
; Department of Clinical Laboratory Diagnosis, Srebrnjak Children's Hospital, Reference Center for Clinical Allergology in Children of the Ministry of Health and Social Welfare, Zagreb, Croatia
Abstract
In the immunoassays, an antibody used as a reagent, detects an analyte (antigen) of interest. Although the noncovalent bound between analyte and complementary antibody is specific, false-positive and false-negative interferences are possible. Some interferences are similar to those in chemical analyses and some are typical only for immunoassays. One should suspect interferences in following cases: upon receiving an unacceptable result, if there is non-linearity during dilution, if there is no agreement with other test results or clinical data, if different immunoassays in determination of the same analyte provide significantly different results. This paper reviews some of the possible interferences: 1) cross-reactivity with endogenous and exogenous non antibody-structured substances; 2) cross-reactivity with endogenous and exogenous antibody-structure substances; 3) the hook effect; and 4) the matrix effect. By knowing and recognizing interferences in immunoassays, one can avoid possible undesired consequences: diagnostic errors, treatment and monitoring of its efficacy, unnecessary additional laboratory testing, unnecessary therapy.
Keywords
immunoassays; interferences; cross-reactivity; prozone effect
Hrčak ID:
32259
URI
Publication date:
5.2.2009.
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