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The CPT® Code 83873 refers to a laboratory test that measures the levels of myelin basic protein (MBP) in cerebrospinal fluid (CSF). Myelin basic protein is a crucial component of the myelin sheath, which serves as a protective covering for nerve cells. The integrity of this protective layer is vital for the proper functioning of the nervous system. When myelin is damaged or breaks down, MBP levels in the CSF can become elevated, indicating potential neurological issues. This elevation is most commonly associated with multiple sclerosis (MS), a chronic disease that affects the central nervous system. However, elevated MBP levels can also result from other conditions, including central nervous system (CNS) trauma, infections, bleeding, various encephalopathies, and strokes. To perform this test, a sample of CSF is collected, typically through a procedure known as a lumbar puncture or spinal tap, which is reported separately. The analysis of the fluid is conducted using a quantitative enzyme-linked immunosorbent assay (ELISA), a sensitive technique that allows for precise measurement of MBP levels in the CSF.
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The test for myelin basic protein (MBP) levels in cerebrospinal fluid (CSF) is indicated for several neurological conditions. The primary indications include:
The procedure for measuring myelin basic protein (MBP) levels in cerebrospinal fluid (CSF) involves several key steps:
After the lumbar puncture procedure, the patient is typically monitored for any immediate complications, such as headache, bleeding, or infection at the puncture site. It is common for patients to experience a headache following the procedure, which may be alleviated with hydration and rest. Patients are usually advised to lie flat for a period after the procedure to reduce the risk of post-lumbar puncture headache. Follow-up appointments may be scheduled to discuss the results of the MBP testing and any further diagnostic or therapeutic steps that may be necessary based on the findings.
| Short Descr | ASSAY OF CSF PROTEIN | Medium Descr | MYELIN BASIC PROTEIN CEREBROSPINAL FLUID | Long Descr | Myelin basic protein, cerebrospinal fluid | 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 | 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. | 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 | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case |
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| 2002-01-01 | Changed | Code description changed. |
| Pre-1990 | Added | Code added. |
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