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Nephelometry is a specialized laboratory technique utilized primarily in the field of immunology to quantitatively measure the concentration of specific proteins, known as globulins, in biological samples such as blood or urine. This method involves the detection of light that is scattered at an angle as it passes through a sample solution. The degree of light scattering is directly proportional to the concentration of the analyte present in the sample, allowing for precise quantification. The CPT® Code 83883 is specifically designated for nephelometric testing of analytes that do not have a more specific coding designation. This code is applicable for various tests that assess different proteins, including but not limited to Kappa/Lambda Quantitative Free Light Chains, Alpha-1-Microglobulin, Alpha-1-Macroglobulin, and Retinol Binding Protein. Each of these tests serves critical diagnostic purposes, such as monitoring plasma cell disorders, identifying renal tubular injury, diagnosing nephrotic syndrome, and evaluating nutritional health related to Vitamin A levels. It is important to report this code for each analyte tested using nephelometry when no specific code exists for that analyte, ensuring accurate billing and documentation in laboratory services.
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The use of CPT® Code 83883 is indicated for the measurement of specific proteins in various clinical scenarios. The following conditions and tests are explicitly associated with this code:
The procedure for nephelometry involves several key steps that ensure accurate measurement of the analytes in question. Each step is critical to the integrity of the test results:
After the nephelometric testing is completed, the laboratory will generate a report detailing the concentrations of the analytes tested. It is essential for healthcare providers to review these results in conjunction with the patient's clinical history and other diagnostic findings. Follow-up actions may include further testing, monitoring of the patient's condition, or adjustments to treatment plans based on the results. Additionally, proper documentation of the test results and the use of CPT® Code 83883 is crucial for accurate billing and compliance with coding guidelines.
| Short Descr | ASSAY NEPHELOMETRY NOT SPEC | Medium Descr | ASSAY OF NEPHELOMETRY EACH ANALYTE NES | Long Descr | Nephelometry, each analyte not elsewhere specified | 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 | 4 | 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. | 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 | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | 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. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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 | 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 | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | GW | Service not related to the hospice patient's terminal condition | GZ | Item or service expected to be denied as not reasonable and necessary | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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Notes
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2011-01-01 | Changed | Short description changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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