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Official Description

Hepatitis B core antibody (HBcAb); IgM antibody

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 86705 refers to the testing of a blood sample for the presence of the hepatitis B core antibody (HBcAb), specifically the IgM antibody. Hepatitis B is a viral infection that leads to inflammation of the liver, caused by the hepatitis B virus (HBV). This infection can manifest in two primary phases: acute and chronic. The core antibody, HBcAb, is produced by the immune system during and after an acute HBV infection. It is important to note that this antibody can be present even in individuals who have successfully cleared the virus without developing a chronic infection. Additionally, HBcAb may also be detected during the chronic phase of the infection. The distinction between the tests for HBcAb is crucial. For instance, CPT® Code 86704 tests for total HBcAb using a chemiluminescent assay, which identifies both IgG and IgM antibodies in a single test without differentiating between the two. This means that while the test can indicate the presence of HBcAb, it does not specify whether the infection is acute or chronic. In contrast, CPT® Code 86705 is specifically designed to test for the IgM antibody to HBcAb, making it a valuable tool for diagnosing an acute hepatitis B infection. The presence of IgM indicates that the infection is in its initial phase, providing critical information for clinical decision-making and patient management.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 86705 is indicated for use in the diagnosis of an acute hepatitis B infection. The specific indications for this test include:

  • Acute Hepatitis B Infection The test is performed when there is a clinical suspicion of an acute hepatitis B infection, characterized by symptoms such as jaundice, fatigue, abdominal pain, and elevated liver enzymes.
  • Monitoring of Hepatitis B Virus Activity It may also be utilized in patients with known hepatitis B infection to assess the activity of the virus and the immune response.

2. Procedure

The procedure for conducting the test associated with CPT® Code 86705 involves several key steps:

  • Step 1: Sample Collection A blood sample is collected from the patient, typically via venipuncture. This sample is essential for the subsequent laboratory analysis to detect the presence of the IgM antibody to HBcAb.
  • Step 2: Laboratory Testing The collected blood sample is sent to a laboratory where it undergoes testing specifically for the IgM antibody to hepatitis B core antigen (HBcAb). This testing is performed using appropriate immunoassay techniques that are designed to identify the presence of the IgM antibody.
  • Step 3: Result Interpretation Once the testing is complete, the laboratory will interpret the results. A positive result for the IgM antibody indicates an acute hepatitis B infection, while a negative result suggests that the patient may not have an active infection or that it is in a different phase.

3. Post-Procedure

After the procedure, the patient may not require any specific post-procedure care related to the blood draw itself, as it is a routine procedure. However, it is important for healthcare providers to discuss the results with the patient once they are available. If the test result is positive for the IgM antibody, further evaluation and management of the hepatitis B infection will be necessary. This may include additional testing, monitoring of liver function, and potential treatment options. Patients should also be informed about the importance of follow-up appointments and any necessary lifestyle modifications to support liver health.

Short Descr HEP B CORE ANTIBODY IGM
Medium Descr HEPATITIS B CORE ANTIBODY HBCAB IGM ANTIBODY
Long Descr Hepatitis B core antibody (HBcAb); IgM antibody
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 235 - Other Laboratory
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
GZ Item or service expected to be denied as not reasonable and necessary
GW Service not related to the hospice patient's terminal condition
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
AY Item or service furnished to an esrd patient that is not for the treatment of esrd
GA Waiver of liability statement issued as required by payer policy, individual case
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
Q4 Service for ordering/referring physician qualifies as a service exemption
Date
Action
Notes
2011-01-01 Changed Short description changed.
1998-01-01 Added First appearance in code book in 1998.
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