Screening method to evaluate point-of-care human chorionic gonadotropin (hCG) devices for susceptibility to the hook effect by hCG β core fragment: evaluation of 11 devices. Clin Chem 2014 Apr;60(4):667-74
Date
01/28/2014Pubmed ID
24463559DOI
10.1373/clinchem.2013.217661Scopus ID
2-s2.0-84897504380 (requires institutional sign-in at Scopus site) 43 CitationsAbstract
BACKGROUND: The predominant hCG variant in urine, hCG β core fragment (hCGβcf), has been demonstrated to cause false-negative results in qualitative point-of-care (POC) hCG devices. This is a major concern for healthcare professionals using POC pregnancy tests. We developed a screening method to evaluate qualitative POC hCG devices for their susceptibility to inhibition by hCGβcf. Using this method, we evaluated the performance of 11 commonly used devices.
METHODS: A wide range of purified hCG and hCGβcf concentrations were mixed and tested on 2 POC devices. By use of those results, a screening method was defined and 9 additional POC devices were evaluated. Two solutions containing (a) 500 pmol/L (171 IU/L) intact hCG with 0 pmol/L hCGβcf and (b) 500 pmol/L intact hCG with 500 000 pmol/L hCGβcf were used to screen all POC devices.
RESULTS: The OSOM and Cen-Med Elite devices were found to be most susceptible to false-negative results due to hCGβcf. The BC Icon 20 and the Alere were the least susceptible. The remaining 7 were moderately affected. Devices that gave the strongest signal with hCGβcf alone were those that were least likely to show a hook effect.
CONCLUSIONS: The screening method put forth here can be used by device users and manufacturers to evaluate POC devices for inhibition by hCGβcf. Of 11 devices evaluated, only 2 have been identified that exhibit minimal to no susceptibility to hCGβcf.
Author List
Nerenz RD, Song H, Gronowski AMAuthor
Robert D. Nerenz PhD Associate Professor in the Pathology and Laboratory Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Chorionic GonadotropinChorionic Gonadotropin, beta Subunit, Human
False Negative Reactions
Female
Humans
Immunoassay
Point-of-Care Systems
Pregnancy
Pregnancy Tests
