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The CPT® Code 82787 refers to the testing of immunoglobulin subclasses, specifically IgG1, IgG2, IgG3, or IgG4. This procedure involves measuring the levels of these specific immunoglobulin subclasses in blood or other body fluids, such as saliva or cerebrospinal fluid (CSF). Immunoglobulins, commonly known as antibodies, play a crucial role in the immune system by identifying and neutralizing pathogens like bacteria and viruses. The evaluation of immunoglobulin levels is essential for diagnosing various medical conditions, including autoimmune diseases, allergies, and certain types of cancers, such as multiple myeloma or macroglobulinemia. The presence and levels of immunoglobulins can provide valuable insights into a patient's immune function. For instance, individuals with frequent infections may undergo this test to assess whether they have low levels of immunoglobulin IgG, which is vital for combating infections. Additionally, monitoring immunoglobulin levels can help evaluate the effectiveness of treatments in patients with conditions like cancer or infections caused by Helicobacter pylori. There are five major types of immunoglobulins: IgA, IgD, IgE, IgG, and IgM, each serving distinct functions in the immune response. IgA is primarily found in mucosal areas, providing a first line of defense against pathogens. IgD is present in tissues lining body cavities, while IgE is associated with allergic reactions. IgG, the most abundant antibody in circulation, is critical for fighting infections and has four subclasses—IgG1, IgG2, IgG3, and IgG4—each tailored to respond to different types of pathogens. For example, IgG1 is particularly effective against viral infections, while IgG2 targets certain bacterial infections. In cases where individuals exhibit selective deficiencies in one or more IgG subclasses, this test can help identify the specific subclass that is lacking, despite normal total IgG levels. The collection of specimens for this test can be performed through venipuncture for blood samples, spinal puncture for CSF samples, or saliva collection. The methodology for testing varies based on the specimen type and the specific immunoglobulin being analyzed. It is important to use the appropriate CPT codes for reporting these tests, with 82784 designated for individual immunoglobulin determinations (IgA, IgD, IgG, or IgM), 82785 for IgE determination, and 82787 for the assessment of IgG subclasses.
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The testing of immunoglobulin subclasses (CPT® Code 82787) is indicated for various clinical scenarios, particularly when evaluating immune function and diagnosing specific conditions. The following are the primary indications for this procedure:
The procedure for testing immunoglobulin subclasses involves several key steps, which are outlined below:
After the immunoglobulin subclass testing is completed, there are several considerations for post-procedure care and follow-up. Patients may experience minimal discomfort at the venipuncture site, which typically resolves quickly. If CSF is collected, patients may be monitored for any potential complications associated with spinal puncture, such as headache or infection. The healthcare provider will review the test results and may discuss the implications of the findings with the patient, including any necessary follow-up tests or treatments based on the immunoglobulin levels measured. It is essential for patients to maintain communication with their healthcare provider regarding any symptoms or concerns that may arise following the procedure.
| Short Descr | IGG 1 2 3 OR 4 EACH | Medium Descr | GAMMAGLOBULIN IMMUNOGLOBULIN SUBCLASSES | Long Descr | Gammaglobulin (immunoglobulin); immunoglobulin subclasses (eg, IgG1, 2, 3, or 4), each | 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 | 4 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| 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. | 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. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | GZ | Item or service expected to be denied as not reasonable and necessary | 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. | 76 | Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | 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 |
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| 2011-01-01 | Changed | Short description changed. |
| 2010-01-01 | Changed | Code description changed. |
| 2008-01-01 | Changed | Code description changed. |
| 2001-01-01 | Changed | Code description changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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