Hepatitis B Surface Antibody

Hepatitis B Surface Antibody

Number
	006395
CPT
	86706
Synonyms
	Antibody to Hepatitis B Surface Antigen ; Anti-HBs ; HBsAb ; Hepatitis Bs Antibody
Specimen
	Serum or plasma
Volume
	1 mL
Minimum Volume
	0.5 mL (Note: This volume does not allow for repeat testing.)
Container
	Red-top tube, gel-barrier tube or lavender-top (EDTA) tube
Collection
	If tube other than a gel-barrier tube is used, transfer the separated serum or plasma to a plastic transport tube.
Storage Instructions
	Refrigerate Sample Stability: Up to 7 days at 2°C to 8°C
Causes for Rejection
	Plasma other than EDTA, PST gel barrier tubes
Reference Interval
	Inconsistent with immunity: 0.00-0.99 Index Value Consistent with immunity: >0.99 Index Value An Index Value of 1.00 is equivalent to 10 mIU/mL. However the magnitude of the Index Value is not indicative of the total amount of antibody present.
Use
	Presence of anti-HBs is an indicator of clinical recovery and subsequent immunity to hepatitis B virus. This test is useful for evaluation of possible immunity in individuals who are at increased risks for exposure to the hepatitis B (ie, hemodialysis unit personnel, venipuncturists, etc). Evaluate the need for hepatitis B immune globulin after needlestick injury; evaluate the need for hepatitis B vaccine and follow immune status after hepatitis B vaccine.
Limitations
	Presence of anti-HBs is not an absolute indicator of resolved hepatitis infection, nor of protection from future infection. Since there are different serologic subtypes of hepatitis B virus, it is possible (and has been reported) for a patient to have antibody to one surface antigen type and to be acutely infected with virus of a different subtype. Thus, a patient may have coexisting HBsAg and anti-HBs. Transfused individuals or hemophiliacs receiving plasma components may give false-positive tests for antibody to hepatitis B surface antigen.
Methodology
	Immunochemiluminometric assay (ICMA)
Additional Information
	Anti-HBs usually can be detected several weeks to several months after HBsAg is no longer found, and it may persist for many years or for life after acute infection has been resolved. It may disappear in some patients, with only antibody to core remaining. Patients with this antibody are not overtly infectious. Presence of the antibody without the presence of the antigen is evidence for immunity from reinfection, with virus of the same subtype (vide supra). Anti-HBs can be induced by vaccination with hepatitis vaccine, now genetically engineered and free of any infective material. This vaccine so far has been safe and effective in protecting recipients from acute hepatitis B. See figure in Hepatitis B Core Antibody, IgM [016881] .
References
	CDC, “Hepatitis B Virus: A Comprehensive Strategy for Eliminating Transmission in the United States Through Universal Childhood Vaccination - Recommendations of the Immunization Practices Advisory Committee (ACIP),” MMWR, 1991, 40(RR-13):1-25. Devine P, Taswell HF, Moore SB, et al, “Passively Acquired Antibody to Hepatitis B Surface Antigen. Pitfall in Evaluating Immunity to Hepatitis B Viral Infections,” Arch Pathol Lab Med, 1989, 113(5):529-31. Edwards MS, “Hepatitis B Serology - Help in Interpretation,” Pediatr Clin North Am, 1988, 35(3):503-15 (review). Foutch PG, Carey WD, Tabor E, et al, “Concomitant Hepatitis B Surface Antigen and Antibody in 13 Patients,” Ann Intern Med, 1983, 99(4):460-3. Francis DP, Hadler SC, Thompson SE, et al, “The Prevention of Hepatitis B With Vaccine: Report of the Centers for Disease Control Multi-Center Efficacy Trial Among Homosexual Men,” Ann Intern Med, 1982, 97(3):362-6. Lee HS and Vyas GN, “Diagnosis of Viral Hepatitis,” Clin Lab Med, 1987, 7(4):741-57. “Protection Against Viral Hepatitis,” Recommendations of the Immunization Practices Advisory Committee (ACIP), MMWR Recomm Rep, 1990, 39(RR-2):1-26. Swenson PD, Escobar MR, Carithers RL Jr, et al, “Failure of Pre-existing Antibody Against Hepatitis B Surface Antigen to Prevent Subsequent Hepatitis B Infection,” J Clin Microbiol, 1983, 18(2):305-9.