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The CPT® Code 82657 refers to a laboratory test that assesses enzyme activity in blood cells, cultured cells, or tissue using a nonradioactive substrate. This test is crucial for monitoring enzyme function, which can be significantly impacted by genetic mutations affecting the proteins responsible for various bodily functions. Enzymes play a vital role in the breakdown and transportation of essential compounds within the body, as well as in the activation and protection of physiological processes. By evaluating enzyme activity in samples such as blood or tissue, healthcare professionals can aid in the diagnosis of certain inherited genetic disorders. For instance, a blood sample is typically collected through a procedure known as venipuncture, which is separately reportable. The applications of CPT® Code 82657 include specific tests such as measuring thiopurine methyltransferase levels in red blood cells to identify individuals at risk for myelosuppression when treated with thiopurines, assessing porphobilinogen (PBG) deaminase activity in whole blood to screen for intermittent porphyria, and quantifying alpha-galactosidase in serum to diagnose Fabry disease in males. Additionally, this code is utilized for examining small bowel tissue for disaccharidase activity through quantitative spectrophotometry, with tissue samples obtained via a separately reportable endoscopy procedure.
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The procedure associated with CPT® Code 82657 is indicated for various conditions and circumstances where enzyme activity needs to be monitored or assessed. The following are specific indications for performing this laboratory test:
The procedure for CPT® Code 82657 involves several key steps that ensure accurate assessment of enzyme activity. Each step is critical for obtaining reliable results.
Post-procedure care for patients undergoing testing associated with CPT® Code 82657 may vary depending on the specific tests performed and the samples collected. For blood sample collection via venipuncture, patients are typically monitored for any immediate adverse reactions, such as bleeding or bruising at the puncture site. If a tissue sample is obtained through endoscopy, patients may require additional monitoring for recovery from sedation and potential complications related to the procedure. It is essential for healthcare providers to provide patients with appropriate aftercare instructions, including any necessary follow-up appointments to discuss test results and further management based on the findings.
| Short Descr | ENZYME CELL ACTIVITY | Medium Descr | NZYM ACTIV BLD CELLS/TISS NONRADACT SUBSTRATE EA | Long Descr | Enzyme activity in blood cells, cultured cells, or tissue, not elsewhere specified; nonradioactive substrate, each specimen | 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 | 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. | 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. | 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. | GW | Service not related to the hospice patient's terminal condition | KX | Requirements specified in the medical policy have been met |
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| 1999-01-01 | Added | First appearance in code book in 1999. |
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