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Official Description

Isocitric dehydrogenase (IDH)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 83570 refers to a laboratory test that measures the level of isocitric dehydrogenase (IDH), an important enzyme involved in cellular metabolism. Isocitric dehydrogenase plays a critical role in the citric acid cycle, a key metabolic pathway that generates energy through the oxidative decarboxylation of isocitrate, resulting in the formation of alpha-ketoglutarate and carbon dioxide (CO2). This enzymatic reaction is essential for the conversion of NAD(P)+ to NAD(P)H, which is vital for various cellular processes. The activity of IDH occurs in multiple cellular compartments, including the cytosol, mitochondria, and peroxisomes, highlighting its significance in diverse metabolic functions. The enzyme is not only crucial for energy production but also for lipid synthesis, oxygen sensing, signal transduction, and providing cellular defense against oxidative stress. Furthermore, mutations in the IDH gene have been linked to certain human cancers, such as gliomas and acute myeloid leukemia, underscoring the clinical relevance of measuring IDH levels in diagnostic and therapeutic contexts.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The measurement of isocitric dehydrogenase (IDH) levels is indicated in various clinical scenarios, particularly in the context of certain malignancies and metabolic disorders. The following conditions may warrant the performance of this laboratory test:

  • Cancer Diagnosis The test is utilized in the evaluation of patients with suspected or diagnosed gliomas and acute myeloid leukemia, where IDH mutations are commonly observed.
  • Monitoring Disease Progression IDH levels may be monitored in patients undergoing treatment for cancers associated with IDH mutations to assess disease progression or response to therapy.
  • Metabolic Disorders The test may also be indicated in the assessment of metabolic disorders that affect the citric acid cycle and related pathways.

2. Procedure

The procedure for measuring isocitric dehydrogenase (IDH) levels involves several key steps to ensure accurate and reliable results. The following outlines the procedural steps:

  • Step 1: Sample Collection A blood sample is collected from the patient, typically via venipuncture. The sample must be handled with care to prevent hemolysis, which could affect the enzyme levels measured.
  • Step 2: Sample Preparation The collected blood sample is processed in the laboratory. This may involve centrifugation to separate the serum or plasma from the cellular components, ensuring that the sample is suitable for analysis.
  • Step 3: Enzyme Assay The laboratory performs an enzyme assay to quantify the level of isocitric dehydrogenase in the prepared sample. This may involve specific reagents and conditions that facilitate the enzymatic reaction, allowing for accurate measurement of IDH activity.
  • Step 4: Result Interpretation Once the assay is complete, the results are analyzed and interpreted by laboratory personnel. The IDH levels are compared against established reference ranges to determine if they are within normal limits or indicative of a pathological condition.

3. Post-Procedure

After the procedure, the patient may be advised on any necessary follow-up actions based on the results of the IDH test. If elevated levels of IDH are detected, further diagnostic evaluations or consultations with oncologists or specialists may be recommended to explore potential underlying conditions, particularly in the context of cancer. Additionally, patients may be monitored for any symptoms or complications related to their condition, and appropriate treatment plans may be developed based on the findings from the IDH level assessment.

Short Descr ASSAY OF IDH ENZYME
Medium Descr ISOCITRIC DEHYDROGENASE
Long Descr Isocitric dehydrogenase (IDH)
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
Date
Action
Notes
Pre-1990 Added Code added.
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