Test Details
Methodology
Immunochemiluminometric assay (ICMA) (HBsAg) and chemiluminescence immunoassay (HDV antibody)
Result Turnaround Time
1 - 5 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Test Includes
Hepatitis B Surface Antigen (HBsAg) Screen; all samples positive with the HBsAg screening assay are confirmed by neutralization at no additional charge. Reflexes to Hepatitis D Virus (HDV) Antibody, IgG and IgM (reported as total HDV antibody) if positive for HBsAg.
Use
This profile is intended to aid in the diagnosis of active hepatitis B virus (HBV) infection (acute and chronic) with reflex of Hepatitis B surface antigen (HBsAg) positive samples to Hepatitis D virus (HDV) antibody testing to identify HDV coinfections. Testing for HDV RNA should be performed on HDV antibody-positive individuals to differentiate between active and resolved HDV infection.
Special Instructions
If reflex HDV Ab test is performed, additional charges/CPT code(s) will apply.
This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Limitations
The performance of the HBsAg assay has not been established with cadaveric specimens, heat-inactivated specimens or body fluids other than serum and EDTA plasma.
HDV antibody reactive specimens should be further tested for HDV RNA to differentiate between active and resolved HDV infection. A nonreactive test result for HDV antibodies does not exclude the possibility of exposure to or infection with HDV. Further investigations with alternative HDV-specific tests are suggested in case of suspected infection despite the negative finding.
The HDV antibody test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Specimen Requirements
Specimen
Serum or plasma
Volume
4 mL
Minimum Volume
1.7 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube, gel-barrier tube or lavender-top (EDTA) tube
Collection Instructions
If tube other than a gel-barrier tube is used, transfer separated serum or plasma to a plastic transport tube.
Stability Requirements
| Temperature | Period |
|---|---|
| Room temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |
| Freeze/thaw cycles | Stable x3 |
Reference Range
Negative
Storage Instructions
Room temperature
Causes for Rejection
Specimens other than serum or EDTA plasma; PST gel-barrier tube; specimens with visible gross microbial contamination