Test Details
Methodology
Immunochemiluminometric assay (ICMA)
Result Turnaround Time
1 - 2 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
Confirmation of positive results is performed as indicated, by a neutralization assay at no additional charge.
• Samples with an index value greater than an established threshold and with positive results for other hepatitis B markers are considered positive for Hepatitis B Surface Antigen without further testing (neutralization testing is not performed).
• Samples with an index value greater than an established threshold but with no other positive results for hepatitis B markers, or with an index value less than an established threshold but above the cutoff for positivity, are confirmed by neutralization.
Use
This assay can be used in conjunction with other serological and clinical information to diagnose individuals with acute or chronic hepatitis B infection. This assay may also be used to screen for hepatitis B infection in pregnant women to identify neonates who are at risk of acquiring hepatitis B during the perinatal period.
Special Instructions
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
Patients who are negative for HBsAg may still have acute type B viral hepatitis. There is sometimes a “core window” stage when HBsAg has become negative and the patient has not yet developed the antibody (anti-HBs). On such occasions, both tests for anti-HBc are usually positive and anti-HBc, IgM is the only specific marker for the diagnosis of acute infection with hepatitis B. In cases with strong clinical suspicion of viral hepatitis, serologic testing should not be limited to detecting HBsAg, but should include a battery of tests to evaluate different stages of acute and convalescent hepatitis.
References
Custom Additional Information
Hepatitis B surface antigen (HBsAg) is a distinctive serological marker of acute or chronic hepatitis B infection. HBsAg is the first antigen to appear following infection with HBV and is generally detected 1-10 weeks after the onset of clinical symptoms. HBsAg assays are routinely used to diagnose suspected HBV infection and monitor the status of infected individuals to determine whether the infection has resolved or the patient has become a chronic carrier of the virus. In patients that recover from HBV infection, HBsAg is undetectable 3-5 months after the onset of infection. In patients with chronic HBV infection, HBsAg remains detectable for life. Prenatal HBsAg screening has been recommended so that newborns from HBV carrier mothers may obtain prophylactic treatment. Persistence of HBsAg, without anti-HBs, with combinations of positivity of anti-HBc, HBeAg, or anti-HBe indicates infectivity and need for investigation for chronic persistent or chronic aggressive hepatitis.
Specimen Requirements
Specimen
Serum or plasma
Volume
3.5 mL
Minimum Volume
1.5 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
Non-EDTA plasma specimen; PST gel-barrier tube
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 006510 | HBsAg Screen | 5196-1 | 006510 | HBsAg Screen | 5196-1 | |
| Order Code | 006510 | |||||
| Order Code Name | HBsAg Screen | |||||
| Order Loinc | 5196-1 | |||||
| Result Code | 006510 | |||||
| Result Code Name | HBsAg Screen | |||||
| UofM | ||||||
| Result LOINC | 5196-1 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 016105 | HBsAg Confirmation | 016105 | HBsAg Confirmation | 7905-3 | |
| Reflex 1 | ||||||
| Order Code | 016105 | |||||
| Order Name | HBsAg Confirmation | |||||
| Result Code | 016105 | |||||
| Result Name | HBsAg Confirmation | |||||
| UofM | ||||||
| Result LOINC | 7905-3 | |||||