Lab Med Qual Assur.  2024 Mar;46(1):66-71. 10.15263/jlmqa.2024.46.1.66.

Assessment of Long-Term Stability of External Quality Control Materials: Defibrinated Pooled Plasma for Examination of Hepatitis Viral Markers

• Kang H
• Jekarl DW
• Yoo SH
• Choi AR
• Oh EJ

• KMID: 2554465
• DOI: http://doi.org/10.15263/jlmqa.2024.46.1.66

Abstract

Since 2016, the external quality assessment program of The Korean Association of External Quality Assessment Service for hepatitis serology has employed pooled serum specimens. Ten test items include hepatitis B virus surface antigen (HbsAg), hepatitis B virus surface antibody (anti-HBs), hepatitis B virus core antibody (anti-HBc) total, anti-HBc immunoglobulin M (IgM), hepatitis B virus envelope antigen (HBeAg), hepatitis B virus envelope antibody (anti-HBe), hepatitis C virus antibody (anti-HCV), hepatitis A virus antibody (anti-HAV) total, anti-HAV immunoglobulin G (IgG), and anti-HAV IgM. We aimed to evaluate the long-term stability of pooled serum specimens using fresh frozen plasma stored at different temperatures. In the first trial conducted in 2019, an additional 432 samples were prepared and tested for long-term stability at room temperature for 2 weeks, refrigerated for 1 month, and frozen (-20℃ and -80℃) for 6 months to 1 year. Furthermore, the stability of the samples was evaluated based on the number of repeated refrigeration and freezing cycles. The prepared pooled sera specimens for hepatitis serology were stable for up to 10 days at 2–8℃, 2–3 months at -20℃ and -80℃, and four freeze-thaw cycles, with the quantitative indices of all tests deviating within 10%. The results of this study are expected to contribute to the stable implementation and quality improvement of the hepatitis virus antigen-antibody test reliability survey project.

Keyword

Hepatitis serology; Stability; Pooled serum; External quality assessment; Fresh frozen plasma