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The CPT® Code 83090 refers to a laboratory test specifically designed to measure the levels of homocysteine in the blood. Homocysteine is a sulfur-containing amino acid that is produced in the body as a result of the metabolism of methionine, an essential amino acid obtained from dietary protein. The measurement of homocysteine levels is significant because elevated concentrations of this amino acid have been identified as a potential risk factor for cardiovascular diseases, including heart attacks and strokes. In addition to cardiovascular risks, high homocysteine levels can also be indicative of other health issues, such as vitamin B deficiencies, which are crucial for the proper metabolism of homocysteine. Other factors that may lead to increased homocysteine levels include intense or prolonged physical exercise, chronic alcoholism, and certain inherited genetic disorders that affect metabolism. The test is performed by obtaining a blood sample through venipuncture, which is a procedure that involves puncturing a vein to collect blood. The analysis of the blood sample is conducted using a quantitative enzymatic technique, which allows for precise measurement of homocysteine levels in either serum or plasma.
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The homocysteine test (CPT® Code 83090) is indicated for the assessment of various health conditions and risk factors. The following are the explicitly provided indications for performing this test:
The procedure for measuring homocysteine levels involves several key steps that ensure accurate results. The first step is the collection of a blood sample, which is performed through a process known as venipuncture. During this procedure, a healthcare professional will locate a suitable vein, typically in the arm, and insert a needle to draw blood into a collection tube. It is essential that the blood sample is collected in a manner that minimizes contamination and ensures the integrity of the sample for testing.
Once the blood sample is obtained, it is processed to separate the serum or plasma from the cellular components. This separation is crucial as the homocysteine levels are measured in the serum or plasma portion of the blood. The next step involves the application of a quantitative enzymatic technique to analyze the sample. This method allows for the precise measurement of homocysteine levels, providing healthcare professionals with the necessary data to assess the patient's risk for cardiovascular disease and other related conditions.
After the homocysteine test is completed, there are generally no specific post-procedure care requirements for the patient. However, it is advisable for patients to remain hydrated and to follow any additional instructions provided by the healthcare professional regarding their overall health and any further testing that may be necessary. The results of the homocysteine test will typically be reviewed by the physician, who will discuss the findings with the patient and determine if any further action or treatment is required based on the levels measured.
| Short Descr | ASSAY OF HOMOCYSTEINE | Medium Descr | ASSAY OF HOMOCYSTEINE | Long Descr | Homocysteine | 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. | 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 | 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 | 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. | 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 | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | 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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| 2023-01-01 | Note | Short description changed. |
| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2006-01-01 | Changed | Code description changed. |
| 2001-01-01 | Added | First appearance in code book in 2001. |
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