Test Details
Methodology
Immunochemiluminometric assay (ICMA); (See individual tests for methodologies)
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.
Use
This test is used to aid in the diagnosis of active Hepatitis A (HAV) infection and differentiate between active and previous infection/vaccination.
HAV Antibody Testing Interpretation Chart
| HAV Total Antibody | HAV IgM | Comments |
|---|---|---|
| Negative | Not done | No evidence of vaccination or previous infection; Susceptible to Hepatitis A infection |
| Positive | Not done | Consistent with recent or remote Hepatitis A infection or antibody response to HAV vaccination |
| Positive | Negative | Consistent with resolved Hepatitis A infection or antibody response to HAV vaccination |
| Positive | Positive | Consistent with active Hepatitis A infection |
Special Instructions
If reflex test is performed, additional charges/CPT code(s) may 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 ro the collection of a sample.
Limitations
This assay has not been FDA cleared or approved for the screening of blood or plasma donors. Assay performance characteristics have not been established for immunocompromised or immunosuppressed patients, cord blood or patients less than 2 years of age.
The performance characteristics of this assay have not been determined for use in cadaveric specimens.
Custom Additional Information
HAV is a picornavirus primarily transmitted via the fecal-oral route. HAV replicates in the liver and is shed in high concentrations in feces from 2-3 weeks before to 1 week after the onset of clinical illness. IgM antibody develops within a week of symptom onset, peaks around three months, and is usually no longer detectable after six months. Many cases of hepatitis A are subclinical, particularly in children. Antibody produced in response to HAV infection (anti-HAV) persists for life and confers protection against reinfection. The presence of IgM antibody to HAV is diagnostic of acute HAV infection. A positive test for total anti-HAV indicates immunity to HAV infection but does not differentiate current from previous HAV infection. Although usually not sensitive enough to detect the low level of protective antibody after vaccination, anti-HAV tests also might be positive after hepatitis A vaccination.
Specimen Requirements
Specimen
Serum
Volume
2 mL
Minimum Volume
0.8 mL (Note: This volume does not allow for repeat testing.)
Container
Gel-barrier tube, red-top tube or serum transfer tube
Collection Instructions
If tube other than a gel-barrier tube is used, transfer separated serum to a screw-cap polypropylene transport tube. Do not freeze gel-barrier tube (pour off serum first).
Stability Requirements
| Temperature | Period |
|---|---|
| Room temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |
| Freeze/thaw cycles | Stable x3 |
Storage Instructions
Room temperature
Causes for Rejection
Heat-inactivated specimens; cord blood; cadaveric specimens; or body fluid other than serum or EDTA plasma; gross hemolysis; excessive lipmia; improper labeling
References
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 144226 | HAV Antibody w/ Rfx | 13951-9 | 006726 | Hep A Ab, Total | 13951-9 | |
| Order Code | 144226 | |||||
| Order Code Name | HAV Antibody w/ Rfx | |||||
| Order Loinc | 13951-9 | |||||
| Result Code | 006726 | |||||
| Result Code Name | Hep A Ab, Total | |||||
| UofM | ||||||
| Result LOINC | 13951-9 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 006734 | Hep A Ab, IgM | 006734 | Hep A Ab, IgM | 13950-1 | |
| Reflex 1 | ||||||
| Order Code | 006734 | |||||
| Order Name | Hep A Ab, IgM | |||||
| Result Code | 006734 | |||||
| Result Name | Hep A Ab, IgM | |||||
| UofM | ||||||
| Result LOINC | 13950-1 | |||||