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The CPT® Code 86431 refers to the quantitative measurement of rheumatoid factor, which is a specific blood test used to assess the levels of rheumatoid factor antibodies in the serum. Rheumatoid factor is an immunoglobulin that can be present in various forms, including IgM, IgG, and IgA. This test is particularly significant in the diagnosis and monitoring of autoimmune conditions, most notably rheumatoid arthritis. Elevated levels of rheumatoid factor can indicate the presence of rheumatoid arthritis, but they may also be associated with other conditions such as hepatitis C, Sjogren syndrome, and various chronic infections. The test is performed on a blood sample that is obtained through venipuncture, a procedure that involves puncturing a vein to collect blood. The serum from the blood sample is then analyzed using a semiquantitative enzyme-linked immunosorbent assay (ELISA), which allows for the precise quantification of rheumatoid factor levels in the serum. This quantitative assessment is crucial for healthcare providers to evaluate the severity of the disease and to guide treatment decisions.
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The rheumatoid factor quantitative test (CPT® Code 86431) is indicated for the following conditions:
The procedure for obtaining a quantitative measurement of rheumatoid factor involves several key steps:
After the procedure, the patient may experience minor discomfort or bruising at the venipuncture site, which typically resolves quickly. There are no specific post-procedure care instructions required for this test, but patients should be advised to report any unusual symptoms or prolonged discomfort. The results of the rheumatoid factor quantitative test will be interpreted by the healthcare provider in conjunction with the patient's clinical history and other diagnostic findings to guide further management and treatment decisions.
| Short Descr | RHEUMATOID FACTOR QUANT | Medium Descr | RHEUMATOID FACTOR QUANTITATIVE | Long Descr | Rheumatoid factor; quantitative | 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. | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | GW | Service not related to the hospice patient's terminal condition | GA | Waiver of liability statement issued as required by payer policy, individual case | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | 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 | 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. | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GC | This service has been performed in part by a resident under the direction of a teaching physician | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GX | Notice of liability issued, voluntary under payer policy | GZ | Item or service expected to be denied as not reasonable and necessary | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | PO | Excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2011-01-01 | Changed | Short description changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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