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The CPT® Code 84100 refers to the laboratory test for measuring inorganic phosphorus, commonly known as phosphate, in blood or urine samples. Phosphate is a vital intracellular anion predominantly located in bone and soft tissue, playing a crucial role in various physiological processes. It is essential for cellular energy production, which is particularly important for the proper functioning of nerves and muscles. Additionally, phosphate is integral to the formation and repair of bones and teeth. Abnormal phosphate levels can indicate underlying health issues; decreased levels are frequently associated with malnutrition and can lead to muscle weakness and neurological dysfunction. Conversely, elevated phosphate levels may suggest problems related to kidney function or parathyroid gland activity. The testing process for CPT® Code 84100 involves obtaining a blood sample through a procedure known as venipuncture, which is separately reportable. The serum or plasma obtained from the blood sample is then analyzed using quantitative spectrophotometry, a method that measures the concentration of phosphate in the sample. This test is critical for diagnosing and monitoring conditions related to phosphate metabolism and overall mineral balance in the body.
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The procedure associated with CPT® Code 84100 is indicated for the assessment of phosphate levels in the body, which can provide valuable insights into various health conditions. The following are specific indications for performing this test:
The procedure for CPT® Code 84100 involves several key steps to ensure accurate measurement of inorganic phosphorus levels. The following outlines the procedural steps:
After the procedure associated with CPT® Code 84100, patients may experience minimal discomfort at the venipuncture site, which typically resolves quickly. There are no specific post-procedure care requirements for this test, but patients are generally advised to maintain hydration and can resume normal activities immediately. The results of the phosphate test are usually available within a short timeframe, allowing for timely clinical decision-making. It is important for healthcare providers to discuss the results with the patient and consider any necessary follow-up actions based on the phosphate levels obtained.
| Short Descr | ASSAY OF PHOSPHORUS | Medium Descr | ASSAY OF PHOSPHORUS INORGANIC | Long Descr | Phosphorus inorganic (phosphate); | 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 | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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 | GW | Service not related to the hospice patient's terminal condition | GZ | Item or service expected to be denied as not reasonable and necessary | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | 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. | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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 | 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 | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 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. | 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. | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | AG | Primary physician | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | CR | Catastrophe/disaster related | LT | Left side (used to identify procedures performed on the left side of the body) | PO | Excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q3 | Live kidney donor surgery and related services | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | QW | Clia waived test | SA | Nurse practitioner rendering service in collaboration with a physician | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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Action
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Notes
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2010-01-01 | Changed | Code description changed. |
| Pre-1990 | Added | Code added. |
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