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An organic acid analysis, as described by CPT® Code 83921, involves the quantitative measurement of a single organic acid in biological specimens such as blood or urine. Organic acids are metabolic by-products that are typically broken down into carbon dioxide and water during normal metabolic processes. However, in individuals with organic acid disorders, certain proteins fail to undergo proper breakdown, leading to various health complications ranging from nutrient deficiencies to severe metabolic crises. These disorders are inherited in an autosomal recessive manner, affecting both males and females equally. The symptoms associated with organic acid disorders can vary significantly based on the specific type of disorder present, and treatment approaches are tailored accordingly. Common organic acids that may be analyzed include 2,4 dichlorophenoxyacetic acid, formic acid, glutaric acid (which is indicative of glutaric acidemia type 1 due to the inability to metabolize lysine and tryptophan), hippuric acid, homogentisic acid, methylhippuric acid, methylmalonic acid (which can indicate a vitamin B12 deficiency), orotic acid, and trichloroacetic acid. The testing methodology utilized may differ based on the specimen type and the specific organic acid being evaluated. It is important to note that if blood is the specimen used for testing, a separate venipuncture procedure must be reported. This code specifically pertains to the quantitative analysis of a single organic acid, distinguishing it from other related codes that either measure multiple organic acids or provide qualitative assessments of their presence in the specimen.
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Organic acid testing is indicated for the evaluation of metabolic disorders that may arise from the improper breakdown of proteins. The following conditions and symptoms may warrant the performance of this test:
The procedure for conducting a quantitative analysis of a single organic acid involves several key steps, which are outlined below:
After the procedure, the healthcare provider may review the results of the organic acid analysis to determine the presence of any metabolic disorders. Depending on the findings, further diagnostic testing or treatment may be necessary. Patients may be monitored for any symptoms related to organic acid disorders, and follow-up consultations may be scheduled to discuss the implications of the test results and potential management strategies. It is essential to ensure that the patient understands the significance of the results and any subsequent steps that may be required for their health care.
| Short Descr | ORGANIC ACID SINGLE QUANT | Medium Descr | ORGANIC ACID 1 QUANTITATIVE | Long Descr | Organic acid, single, quantitative | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | GA | Waiver of liability statement issued as required by payer policy, individual case | 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. | 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. | 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. | 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. | 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 | 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 | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 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) | 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 | 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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| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Added | First appearance in code book in 2001. |
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