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The CPT® Code 86161 refers to a laboratory test that measures the functional activity of complement components in the blood. Complement factors are crucial proteins that play a significant role in the immune system, particularly in the clearance of immune complexes from the bloodstream. The complement system operates through a cascade mechanism, leading to the formation of the membrane attack complex (MAC), which is essential for both innate and adaptive immune responses. This process involves the attachment of complement proteins to the cell membrane of pathogens, resulting in the lysis or rupture of these cells, thereby aiding in the elimination of infections. Individuals exhibiting low levels of complement functional activity are at an increased risk for infections due to the compromised ability of their immune system to respond effectively. To perform this test, a blood sample is collected through a venipuncture, which is a separately reportable procedure. The complement functional activity is then assessed using specific methodologies, predominantly through a quantitative hemolytic assay. The code 86161 should be reported for each complement functional activity tested, including components 1, 6, 7, 8, 9, and the C1-esterase inhibitor functional activity.
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The complement functional activity test, represented by CPT® Code 86161, is indicated for various clinical scenarios where assessment of the complement system is necessary. This test is particularly relevant for patients who exhibit symptoms or conditions that may suggest complement deficiencies or dysfunctions. The following are specific indications for performing this test:
The procedure for testing complement functional activity involves several key steps that ensure accurate measurement of complement levels in the blood. The following outlines the procedural steps involved:
After the complement functional activity test is performed, there are several considerations for post-procedure care and follow-up. Patients may experience minor discomfort or bruising at the venipuncture site, which typically resolves without intervention. It is advisable for patients to be informed about potential signs of complications, such as excessive bleeding or infection at the site, and to seek medical attention if these occur. The results of the complement testing will be reviewed by the healthcare provider, who will discuss the findings with the patient and determine any necessary follow-up actions or additional testing based on the results. This may include further evaluation of the immune system or adjustments to treatment plans for underlying conditions.
| Short Descr | COMPLEMENT/FUNCTION ACTIVITY | Medium Descr | COMPLEMENT FUNCTIONAL ACTIVITY EACH COMPONENT | Long Descr | Complement; functional activity, each component | 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 | 2 | 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. | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | Q4 | Service for ordering/referring physician qualifies as a service exemption | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | GW | Service not related to the hospice patient's terminal condition |
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| 1993-01-01 | Added | First appearance in code book in 1993. |
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