Evaluation of AIA-PACK CL Prolactin II reagent

Abstract

There are two types of prolactin (PRL): (1) PRL, which has physiological activity, and (2) macroprolactin, which is bound by IgG and has no physiological activity. Macroprolactin in the blood may lead to false positive PRL concentrations in immunological measurements. This may result in misdiagnosis of hyperprolactinemia, leading to unnecessary tests and treatments. Therefore, it is clinically important to have an assay kit that can accurately separate PRL and macroprolactin. In this study, we compared the test performance of conventional “AIA-PACK CL Prolactin (Tosoh Co., Ltd.)” and newly developed “AIA-PACK CL Prolactin II (Tosoh Co., Ltd.)”, which was developed to reduce the reactivity with macro macroprolactin. Repeatability, reproducibility, dilution linearity, and influence of interfering substances of AIA-PACK CL Prolactin II were tested, and those results were acceptable.The correlation with the conventional AIA-PACK CL Prolactin and newly developed “AIA-PACK CL Prolactin II was as follows: regression equation: y = 1.01x + 0.12, r = 0.992, (n = 100). The results of the PEG-treatment test and gel filtration analysis of the two cases in which the measured values with AIA-PACK CL Prolactin II deviated from those with the current reagent by more than 20%, both had macroprolactin, confirming that this reagent does not measure macroprolactin compared to the current reagent. The use of AIA-PACK CL Prolactin II in clinical practice can reduce the incidence of hyperprolactinemia diagnosis even when macroprolactin is present in the blood, thereby avoiding unnecessary tests and treatments.