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Phenylalanine is an essential amino acid that is naturally present in many protein-containing foods. The CPT® Code 84030 refers to a blood test specifically designed to measure the levels of phenylalanine in the bloodstream. This test is crucial for identifying individuals with phenylketonuria (PKU), a genetic disorder caused by a deficiency in the hepatic enzyme phenylalanine hydroxylase (PAH). When this enzyme is nonfunctional due to a genetic mutation, the body is unable to convert phenylalanine into another amino acid called tyrosine. As a result, phenylalanine accumulates in the blood, which can lead to severe neurological damage if not detected and managed early. The blood test for phenylalanine is typically performed as part of a Newborn Screening Panel, ensuring that infants are screened shortly after birth for this potentially harmful condition. Various testing methods may be employed to measure phenylalanine levels, including the bacterial inhibition assay known as the Guthrie test, as well as fluorometric or photometric immunoassays. Additionally, tandem mass spectrometry may be utilized to measure amino acids, providing accurate and reliable results for the diagnosis of PKU.
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The blood test for phenylalanine (CPT® Code 84030) is indicated for the following conditions:
The procedure for testing phenylalanine levels in the blood involves several key steps:
After the blood sample has been collected and tested, the results are typically available within a few days. If elevated levels of phenylalanine are detected, further diagnostic testing may be recommended to confirm a diagnosis of PKU. In cases where PKU is confirmed, immediate dietary management is crucial to prevent the accumulation of phenylalanine, which can lead to serious health issues. Patients diagnosed with PKU will require ongoing monitoring of their phenylalanine levels and may need to adhere to a specialized diet low in phenylalanine throughout their lives. Regular follow-up appointments with healthcare providers are essential to ensure proper management and to adjust dietary plans as necessary.
| Short Descr | ASSAY OF BLOOD PKU | Medium Descr | ASSAY OF PHENYLALANINE BLOOD | Long Descr | Phenylalanine (PKU), blood | 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 | 1 | 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. |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| Pre-1990 | Added | Code added. |
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