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The CPT® Code 83735 refers to the laboratory test for measuring magnesium levels in the body. Magnesium is a vital dietary mineral that plays a crucial role in various physiological functions, including enzyme activity, energy production, and the regulation of muscle contraction and relaxation. This test can be performed on different types of specimens, including blood, urine, or fecal samples, to assess the magnesium concentration. Low magnesium levels can be indicative of several health issues, such as severe burns, metabolic disorders, the effects of certain medications, and low blood calcium levels. The testing process involves obtaining a blood sample through venipuncture, which is a separate reportable procedure. For the analysis, red blood cells (RBCs) are evaluated using quantitative inductively coupled plasma-mass spectrometry, while serum or plasma samples are analyzed using quantitative spectrophotometry. Additionally, a 24-hour voided urine specimen can be tested using quantitative spectrophotometry, and a random or 24-hour fecal sample may also be assessed using the same spectrophotometric method. This comprehensive approach ensures accurate measurement of magnesium levels, which is essential for diagnosing and managing various medical conditions.
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The magnesium test (CPT® Code 83735) is indicated for the evaluation of magnesium levels in patients who may be experiencing symptoms or conditions related to magnesium deficiency or excess. The following are specific indications for performing this test:
The procedure for testing magnesium levels involves several steps, each critical for ensuring accurate results. The following outlines the procedural steps:
After the magnesium testing procedure, there are no specific post-procedure care requirements for patients. However, it is essential to monitor the results and follow up with appropriate clinical evaluation based on the findings. Patients may be advised to discuss their results with their healthcare provider to understand the implications of their magnesium levels and any necessary interventions or dietary adjustments. Additionally, if a blood sample was taken, patients should be informed about potential minor side effects from venipuncture, such as bruising or discomfort at the site of the needle insertion.
| Short Descr | ASSAY OF MAGNESIUM | Medium Descr | ASSAY OF MAGNESIUM | Long Descr | Magnesium | 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 | 4 | 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 | 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. | GZ | Item or service expected to be denied as not reasonable and necessary | GW | Service not related to the hospice patient's terminal condition | Q4 | Service for ordering/referring physician qualifies as a service exemption | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | 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. | 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. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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. | 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 | 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 | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | 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. | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | GC | This service has been performed in part by a resident under the direction of a teaching physician | SA | Nurse practitioner rendering service in collaboration with a physician | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | X1 | Continuous/broad services: for reporting services by clinicians, who provide the principal care for a patient, with no planned endpoint of the relationship; services in this category represent comprehensive care, dealing with the entire scope of patient problems, either directly or in a care coordination role; reporting clinician service examples include, but are not limited to: primary care, and clinicians providing comprehensive care to patients in addition to specialty care | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | 58 | Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78. | 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. | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CR | Catastrophe/disaster related | FA | Left hand, thumb | GE | This service has been performed by a resident without the presence of a teaching physician under the primary care exception | GX | Notice of liability issued, voluntary under payer policy | HO | Masters degree level | JZ | Zero drug amount discarded/not administered to any patient | KX | Requirements specified in the medical policy have been met | LT | Left side (used to identify procedures performed on the left side of the body) | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | PO | Excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q3 | Live kidney donor surgery and related services | 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) | QW | Clia waived test | RT | Right side (used to identify procedures performed on the right side of the body) | TR | School-based individualized education program (iep) services provided outside the public school district responsible for the student | 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 | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| Pre-1990 | Added | Code added. |
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