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The CPT® Code 84540 refers to the laboratory test for measuring urea nitrogen in urine, specifically known as urine urea nitrogen. Urea nitrogen is a waste product formed in the liver during the metabolism of proteins, which undergoes a series of chemical reactions collectively known as the urea cycle or Krebs-Henseleit cycle. Once produced, urea enters the bloodstream and is subsequently filtered by the kidneys, where it is excreted in the urine. The measurement of blood urea nitrogen (BUN) levels is crucial for assessing renal function, as it provides insights into how well the kidneys are performing their filtering duties. This test is particularly important for monitoring patients with existing renal diseases and evaluating the effectiveness of dialysis treatments. Additionally, BUN levels may be analyzed in patients suffering from acute or chronic illnesses that could potentially impact kidney function. It is important to note that this specific code (84540) pertains solely to the measurement of BUN in urine, distinguishing it from related codes such as 84525, which involves a reagent strip test, and 84545, which requires a 24-hour urine collection for analysis.
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Urine urea nitrogen testing, represented by CPT® Code 84540, is indicated for various clinical scenarios, particularly those involving renal function assessment and monitoring. The following conditions and situations warrant the performance of this test:
The procedure for obtaining urine urea nitrogen measurements involves several key steps, ensuring accurate and reliable results. The following outlines the procedural steps associated with CPT® Code 84540:
After the urine urea nitrogen test is performed, there are generally no specific post-procedure care requirements for the patient, as the test is non-invasive and does not involve any significant risks. Patients can resume their normal activities immediately following the sample collection. However, it is important for healthcare providers to discuss the results with the patient once they are available, as this will help in determining any necessary follow-up actions or treatments based on the BUN levels measured. Regular monitoring may be recommended for patients with ongoing renal issues or those undergoing dialysis.
| Short Descr | ASSAY OF URINE/UREA-N | Medium Descr | ASSAY OF UREA NITROGEN URINE | Long Descr | Urea nitrogen, urine | 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. | 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. | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | Q3 | Live kidney donor surgery and related services | Q4 | Service for ordering/referring physician qualifies as a service exemption |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| Pre-1990 | Added | Code added. |
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