ĐÁNH GIÁ TÍNH ĐỒNG NHẤT, ĐỘ ỔN ĐỊNH CỦA MẪU NƯỚC TIỂU GIẢ ĐỊNH CHỨA HCG ỨNG DỤNG TRONG CHƯƠNG TRÌNH NGOẠI KIỂM TỔNG PHÂN TÍCH NƯỚC TIỂU

Abstract

Objectives: To evaluate the homogeneity and stability of artificial urine samples containing hCG for use in an external quality assessment program for urinalysis. Study subjects: Parameters in artificial urine samples used in a comprehensive urinalysis external quality assessment program. Study site: Quality control center for medical laboratory - University of medicine and pharmacy at Ho Chi Minh city. Method: An experimental study was conducted. Results: Fifteen parameters were evaluated, including glucose, ketones, nitrite, leukocytes, urobilinogen, bilirubin, blood, protein, albumin, creatinine, calcium, ascorbic acid, pH, specific gravity, and hCG. Lot 1 (negative sample): The artificial urine sample containing 15 parameters at negative/normal levels, including negative hCG, demonstrated acceptable homogeneity and stability for up to 3 months when stored at 2–8°C, with p ≥ 0.05. Lot 2 (positive sample): The artificial urine sample containing 11 parameters at ++/+++ positive levels, negative ascorbic acid, pH 7.0, and a specific gravity of 1.025 was subdivided into four sub-lots with hCG concentrations of 25 mIU/mL (Lot 2A), 100 mIU/mL (Lot 2B), 500 mIU/mL (Lot 2C), and 1000 mIU/mL (Lot 2D). All sub-lots met homogeneity and stability criteria for up to 3 months at 2-8°C, with p ≥ 0.05. Conclusion: The study standardized the production procedure and demonstrated that the artificial urine sample lots containing 15 parameters, including hCG, exhibited acceptable homogeneity and stability for up to 3 months at 2-8°C. These results support the suitability of the samples for use in urinalysis external quality assessment programs, contributing to reduced dependence on imported materials and improving the quality of urinalysis testing in Vietnam.