Overview: Hepatitis B Surface Antigen CTL TestIntroduction: The Hepatitis B Surface Antigen CTL Test detects hepatitis B surface antigen in dilution to diagnose hepatitis B, causing jaundice or liver pain. Aligned with 2023 AASLD guidelines, it uses an immunoassay for high sensitivity, aiding in infectious disease screening. This test is critical for guiding diagnosis, treatment, and improving outcomes in serology for patients with suspected hepatitis B infection.
Other Names: HBs Ag CTL Assay, Hepatitis B Antigen Test.
FDA Status: FDA-cleared diagnostic test, meeting serology standards for diagnostic accuracy.
Historical Milestone: Hepatitis B testing began in the 1970s with antigen discovery. Immunoassays improved in the 1980s, enhancing accuracy for hepatitis B diagnosis.
Purpose: Diagnoses hepatitis B, guides antiviral treatment, and monitors HBsAg levels in patients with jaundice or liver pain.
Test Parameters: 1. Hepatitis B Surface Antigen
Pretest Condition: No fasting required. Collect serum at any time. Report symptoms like jaundice or liver pain, and list medications or vaccination history.
Specimen: 2-5 mL serum (SST). Centrifuge within 1 hour. Transport in a biohazard bag within 8 hours.
Sample Stability at Room Temperature: 8 hours
Sample Stability at Refrigeration: 7 days
Sample Stability at Frozen: 6 months
Medical History: Document jaundice, liver pain, or history of hepatitis B. Include current medications, vaccination status, or risk factors (e.g., IV drug use).
Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for antiviral therapy.
Procedural Considerations: Uses an immunoassay to detect HBsAg in dilution. Results are available in 1-2 days, enabling rapid clinical decisions.
Factors Affecting Result Accuracy: Recent vaccination, hemolysis, or improper storage can affect results. Early infection may yield false negatives.
Clinical Significance: Positive HBsAg confirms hepatitis B infection, prompting antiviral treatment. Negative results may require further testing to rule out early infection.
Specialist Consultation: Consult a hepatologist or infectious disease specialist for result interpretation and treatment planning.
Additional Supporting Tests: HBV DNA, anti-HBc, or liver function tests to confirm hepatitis B and assess liver damage.
Test Limitations: False negatives may occur in early infection or low viral load. Results require clinical correlation.
References: AASLD Hepatitis B Guidelines, 2023; Hepatology, Lok AS, 2022.
