[Performance Utility of High Sensitivity Quantitative Assay for HBs Antigen]

Area of Science:

• Clinical Chemistry
• Virology
• Immunodiagnostics

Background:

• Hepatitis B virus (HBV) reactivation poses a significant clinical challenge.
• Early detection of HBV surface antigen (HBsAg) is crucial for managing reactivation.
• A high sensitivity quantitative assay (HBsAg-HQ) has been developed for improved HBsAg detection.

Purpose of the Study:

• To evaluate the performance and utility of the HBsAg-HQ assay.
• To establish and validate operational procedures for the HBsAg-HQ assay within a laboratory setting.
• To assess the clinical significance of HBsAg-HQ assay results in a routine testing workflow.

Main Methods:

• Development of operational procedures integrating sample transport and laboratory information systems.
• Performance evaluation using internal quality control (IQC) data.
• Analysis of 13,762 routine clinical samples over an 8-month period.
• Inhibition tests to assess non-specific reactivity.

Main Results:

• HBsAg-HQ assay demonstrated good accuracy with low coefficient of variation (CV: 1.6-2.7%) in IQC data.
• Out of 13,762 samples, 8.5% were HBsAg positive, with negative samples well below the cut-off.
• Identified 12 false positive results among weakly positive samples, which were corrected upon re-measurement.
• Non-specific reactivity was observed in 20 out of 52 weakly positive samples, particularly in patients with connective tissue disease or malignancy.

Conclusions:

• The established operational procedures for the HBsAg-HQ assay ensure efficient workflow and reliable routine testing.
• The HBsAg-HQ assay provides high sensitivity for earlier HBV reactivation detection.
• The assay's ability to reduce false positives enhances its clinical utility in managing HBV infections.