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The CPT® Code 86357 refers to the measurement of total natural killer (NK) cell count through a blood test. Natural killer cells are a type of large granular lymphocyte that plays a crucial role in the immune system, particularly in the body's defense against tumors and virally infected cells. This test is essential for assessing the overall function of the immune system, as NK cells are integral to the body's ability to respond to infections and malignancies. The test is often performed alongside other immunological assessments, including tests for B-cells, T-cells, and specific subsets of T-cells, to provide a comprehensive evaluation of immune status. The procedure involves obtaining a blood sample through venipuncture, which is a standard method for collecting blood for laboratory analysis. The analysis of the blood sample is conducted using quantitative flow cytometry, a sophisticated technique that allows for the precise counting and characterization of different cell types within the blood. This detailed assessment is vital for diagnosing and monitoring various health conditions related to immune function.
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The total count of natural killer (NK) cells is performed for various clinical indications, particularly when assessing immune function. The following conditions may warrant this test:
The procedure for measuring total natural killer (NK) cell count involves several key steps:
After the procedure, patients 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, and patients can generally resume normal activities immediately. However, if any unusual symptoms occur, such as excessive bleeding or signs of infection at the puncture site, patients should contact their healthcare provider. The results of the NK cell count will be discussed with the patient during a follow-up appointment, where further diagnostic or therapeutic steps may be determined based on the findings.
| Short Descr | NK CELLS TOTAL COUNT | Medium Descr | NATURAL KILLER CELLS TOTAL COUNT | Long Descr | Natural killer (NK) cells, total count | 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 | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | GZ | Item or service expected to be denied as not reasonable and necessary | 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. | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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. | 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 | 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. |
| 2006-01-01 | Added | First appearance in code book in 2006. |
| 1992-12-31 | Deleted | Code deleted. |
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