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The CPT® Code 84166 refers to a laboratory test that involves the electrophoretic fractionation and quantitation of proteins found in various body fluids, specifically those with concentration such as urine and cerebrospinal fluid (CSF). This procedure is essential for measuring the levels of proteins present in these fluids, which can provide critical insights into a patient's health status. Elevated protein levels in CSF may indicate serious conditions such as central nervous system tumors or various neurological disorders, while increased protein levels in urine can suggest kidney disease or damage. The test utilizes quantitative electrophoresis, a technique that separates proteins based on their size and charge, allowing for precise measurement and analysis. It is important to note that CSF is typically collected through a lumbar puncture, also known as a spinal tap, which is a separate procedure that must be reported independently. In contrast, urine samples are usually collected over a 24-hour period to ensure accurate assessment of protein concentration. This test is particularly valuable in diagnosing and monitoring conditions that affect protein levels in these critical body fluids.
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The procedure associated with CPT® Code 84166 is indicated for the evaluation of protein levels in body fluids, particularly in the following scenarios:
The procedure for CPT® Code 84166 involves several key steps to ensure accurate testing of protein levels in body fluids.
After the procedure, it is important to monitor the patient for any potential complications arising from the lumbar puncture, such as headache or infection. The results of the protein electrophoresis will be analyzed and reported, providing valuable information regarding the patient's health status. Follow-up may be necessary to discuss the findings and any further diagnostic steps or treatments that may be required based on the protein levels detected in the CSF or urine.
| Short Descr | PROTEIN E-PHORESIS/URINE/CSF | Medium Descr | PROTEIN ELECTROP FXJ&QUAN OTH FLUS CONCENTRATI | Long Descr | Protein; electrophoretic fractionation and quantitation, other fluids with concentration (eg, urine, CSF) | Status Code | Active Code | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 6 - Laboratory Physician Interpretation Code | Multiple Procedures (51) | 0 - No payment adjustment rules for multiple procedures apply. | Bilateral Surgery (50) | 0 - 150% payment adjustment for bilateral procedures does NOT apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 0 - Payment restriction for assistants at surgery applies to this procedure... | Co-Surgeons (62) | 0 - Co-surgeons not permitted for this procedure. | Team Surgery (66) | 0 - Team surgeons not permitted for this procedure. | 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 | 233 - Laboratory - Chemistry and Hematology |
| 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. | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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. | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | 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 | 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. | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | 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. | GZ | Item or service expected to be denied as not reasonable and necessary | GA | Waiver of liability statement issued as required by payer policy, individual case | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner | 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. | 22 | Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service. | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | CR | Catastrophe/disaster related | 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 | 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 | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | QT | Recording and storage on tape by an analog tape recorder | SA | Nurse practitioner rendering service in collaboration with a physician | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2005-01-01 | Added | First appearance in code book in 2005. |
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