A two-center international evaluation of the Immulite 2000 automated serum gastrin assay

Objectives: To assess the performance of the Immulite 2000 serum gastrin assay. Design and methods: Two-center validation and comparison with two manual gastrin assays. Results: Serum, serum separator, EDTA and heparin tube results differed <20%. Samples showed <20% degradation for <6 h at room temperature, 3-day-refrigerated, and underwent 3 freeze–thaw cycles. Imprecision was <8% between 20 and 824 ng/L (10–393 pmol/L). Spike recovery was 88.5–106%, and recovery on dilution was 62–135%. There were no interferences from gastrin 1–14, pentagastrin, and cholecystokinin (CCK) 1–33 and CCK 26–33. The fasting reference range was <100 ng/L (<48 pmol/L). Regression slopes to the manual assays were 0.9 and 0.97, with comparable clinical performance. Conclusions: The Immulite 2000 assay is precise, accurate, and fast and compares well with established gastrin assays.