A Search for Uniformity in Human Chorionic Gonadotropin (hCG) Reporting

Abstract

Varying reports across different laboratories or across different analysers in the same lab for the same sample is not an uncommon phenomena. Experts call this a lack of harmonization. A test that is harmonized provides the same results regardless of the manufacturer of reagents used or the laboratory where the test is performed. When laboratory tests are not harmonized, the entire continuum of patient care can be affected in a number of ways. Here, we present a case of varying reports for a single serum human chorionic gonadotropin (hCG) sample on two different immunoassay platforms for a young female presenting with an abdominopelvic mass. The lab reports for serum hCG for this particular patient showed inconsistent results with the same sample within the same lab. The phenomena behind this was lack of harmonization of test results. We introspect many of the factors responsible for lack of uniformity in hCG results amongst the major ones being with use of antibodies directed against different epitopes of hCG (analyte) and the heterogeneity of the hCG molecule itself. Harmonization is a process to ensure that different clinical testing procedures used by different laboratories give equivalent results. Harmonizing test results will enable healthcare providers to use clinical guidelines with greater confidence for diagnosing disease and managing patients.

Keywords: Case report; Harmonization; Human chorionic gonadotropin (hCG); Immunoassay.

Fig. 1

Metabolism of variants forms of hCG (adapted from Cole LA, Clinical Chemistry)