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The CPT® Code 84157 refers to a laboratory test that measures the total protein concentration in body fluids other than blood or urine, specifically targeting fluids such as cerebrospinal fluid (CSF) and synovial fluid. This test is crucial for diagnosing various medical conditions, as it provides insights into the protein levels present in these fluids. Elevated protein levels in CSF can indicate serious conditions such as tumors, bleeding, inflammation, or injury affecting the brain or central nervous system. Conversely, a decrease in protein levels may suggest a rapid turnover or replacement of CSF, which can occur in certain medical scenarios. In the case of synovial fluid, an increase in total protein levels is typically associated with inflammatory processes. The collection of CSF is performed through a procedure known as a lumbar puncture, commonly referred to as a spinal tap, while synovial fluid is obtained via arthrocentesis, a procedure that involves the aspiration of fluid from the affected joint. The analysis of these body fluids is conducted using reflectance spectrophotometry, a method that allows for accurate measurement of protein concentrations.
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The test coded under CPT® 84157 is indicated for the evaluation of various medical conditions that may affect the central nervous system or joints. The following are specific indications for performing this test:
The procedure for obtaining and testing total protein levels in body fluids involves several key steps, which are outlined below:
After the procedures for collecting CSF or synovial fluid, patients may require specific post-procedure care. For lumbar puncture, patients are often advised to lie flat for a period to reduce the risk of headaches, which can occur as a complication. Monitoring for any signs of infection or adverse reactions at the puncture site is also essential. In the case of arthrocentesis, patients should be observed for swelling, pain, or signs of infection in the joint from which the fluid was aspirated. Follow-up appointments may be necessary to discuss the results of the protein analysis and any further diagnostic or therapeutic steps that may be indicated based on the findings.
| Short Descr | ASSAY OF PROTEIN OTHER | Medium Descr | PROTEIN TOTAL XCPT REFRACTOMETRY OTH SRC | Long Descr | Protein, total, except by refractometry; other source (eg, synovial fluid, 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) | Yes | 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 | 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. | 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. | 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 | GW | Service not related to the hospice patient's terminal condition | Q4 | Service for ordering/referring physician qualifies as a service exemption | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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| 2011-01-01 | Changed | Short description changed. |
| 2004-01-01 | Added | First appearance in code book in 2004. |
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