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Official Description

Amino acids, 6 or more amino acids, quantitative, each specimen

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 82139 refers to the quantitative measurement of six or more amino acids in a specimen, which can be derived from blood, urine, or cerebrospinal fluid (CSF). Amino acids are organic compounds that serve as the fundamental building blocks of proteins, consisting of an amine group, a carboxylic acid group, and a unique side chain that distinguishes each amino acid from one another. These molecules play a vital role in various metabolic processes and are essential for sustaining life. The analysis of amino acid levels is crucial in diagnosing and managing several medical conditions, particularly those related to metabolic disorders. Symptoms that may prompt the need for amino acid testing include failure to thrive, persistent vomiting, neurological deterioration, hyperammonemia, extreme lethargy, and metabolic acidosis. Conditions such as acute life-threatening episodes and inborn errors of metabolism are significant indicators for conducting an amino acid analysis. The testing process typically involves ion exchange chromatography, which allows for the precise quantification of each amino acid present in the specimen. The specific amino acids analyzed can vary based on the clinical context; for instance, a cystinuria panel specifically evaluates four amino acids: arginine, cystine, lysine, and ornithine. It is important to note that CPT® Code 82139 is applicable for the quantitative analysis of six or more amino acids, while CPT® Code 82136 is designated for the analysis of two to five amino acids. Each code is reported for every separate specimen that is tested.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The quantitative analysis of amino acids using CPT® Code 82139 is indicated in various clinical scenarios where abnormal amino acid levels may suggest underlying metabolic disorders. The following conditions and symptoms may warrant this testing:

  • Failure to Thrive - A condition often seen in infants and children where they do not gain weight or grow as expected, potentially indicating metabolic issues.
  • Persistent Vomiting - Ongoing vomiting can lead to dehydration and electrolyte imbalances, prompting the need for amino acid analysis to assess metabolic function.
  • Neurological Deterioration - Changes in neurological status may suggest metabolic disturbances, including those related to amino acid imbalances.
  • Hyperammonemia - Elevated ammonia levels in the blood can indicate a problem with amino acid metabolism, necessitating further investigation through amino acid testing.
  • Extreme Lethargy - Unexplained fatigue or lack of energy may be linked to metabolic disorders, prompting the need for amino acid level assessment.
  • Metabolic Acidosis - A condition characterized by an excess of acid in the body fluids, which may be related to amino acid metabolism issues.
  • Acute Life-Threatening Episodes - Sudden and severe metabolic crises that require immediate evaluation of amino acid levels to guide treatment.
  • Inborn Errors of Metabolism - Genetic disorders that affect metabolic pathways, often requiring amino acid analysis for diagnosis and management.

2. Procedure

The procedure for conducting a quantitative amino acid analysis using CPT® Code 82139 involves several key steps to ensure accurate measurement of amino acid levels in the specimen collected.

  • Step 1: Specimen Collection - A sample is obtained from the patient, which can be blood, urine, or cerebrospinal fluid (CSF). The choice of specimen type depends on the clinical context and the specific amino acids being evaluated.
  • Step 2: Specimen Preparation - The collected specimen is prepared for analysis, which may involve processes such as centrifugation for blood samples to separate plasma or serum, or specific handling protocols for urine and CSF samples to preserve amino acid integrity.
  • Step 3: Ion Exchange Chromatography - The prepared specimen undergoes testing using ion exchange chromatography, a technique that separates amino acids based on their charge and allows for the quantification of each amino acid present in the sample.
  • Step 4: Quantitative Analysis - The results of the chromatography are analyzed to determine the concentration of each amino acid. This quantitative analysis provides critical information regarding the levels of amino acids in the specimen.
  • Step 5: Reporting Results - The findings are compiled into a report that details the levels of each amino acid tested. This report is then used by healthcare providers to make informed decisions regarding diagnosis and treatment.

3. Post-Procedure

After the amino acid analysis is completed, the healthcare provider will review the results in conjunction with the patient's clinical presentation and history. Depending on the findings, further diagnostic testing or interventions may be necessary. Patients may be monitored for any symptoms related to amino acid imbalances, and treatment plans may be adjusted based on the quantitative results obtained. It is essential for healthcare providers to communicate the results effectively to the patient and discuss any implications for their health and management moving forward.

Short Descr AMINO ACIDS QUAN 6 OR MORE
Medium Descr AMINO ACIDS 6/> AMINO ACIDS QUANTITATIVE EA SPE
Long Descr Amino acids, 6 or more amino acids, quantitative, each specimen
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.
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.
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
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
2011-01-01 Changed Short description changed.
1999-01-01 Added First appearance in code book in 1999.
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Description
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