Test Catalog

Test Id : AAPD

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Amino Acids, Quantitative, Random, Urine

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Overview

Test Catalog

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with possible inborn errors of metabolism using random urine specimens

 

May aid in evaluation of endocrine disorders, liver diseases, muscle diseases, neoplastic diseases, neurological disorders, nutritional disturbances, kidney failure, and burns

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes quantitation of the following amino acids: taurine, threonine, serine, asparagine, hydroxyproline, glutamic acid, glutamine, aspartic acid, ethanolamine, sarcosine, proline, glycine, alanine, citrulline, alpha-aminoadipic acid, alpha-amino-n-butyric acid, valine, cystine, cystathionine, methionine, isoleucine, leucine, tyrosine, phenylalanine, beta-alanine, beta-aminoisobutyric acid, ornithine, lysine, 1-methylhistidine, histidine, 3-methylhistidine, argininosuccinic acid, allo-isoleucine, homocitrulline, gamma-amino-n-butyric acid, hydroxylysine, tryptophan, and arginine.

Method Name
A short description of the method used to perform the test

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Portions of this test are covered by patents held by Quest Diagnostics

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Amino Acids, QN, Random, U

Aliases
Lists additional common names for a test, as an aid in searching

1-Methylhistidine

3-Methylhistidine

Alanine

Allo-Isoleucine

Alpha-Aminoadipic Acid

Alpha-Amino-n-Butyric Acid

Arginine

Argininosuccinic Acid

Asparagine

Aspartic Acid

Beta-Alanine

Beta-Aminoisobutyric Acid

Citrulline

Cystathionine

Ethanolamine

Gamma-Amino-n-Butyric Acid

Glutamic Acid

Glutamine

Glycine

Histidine

Homocitrulline

Hydroxylysine

Hydroxyproline

Isoleucine

Leucine

Lysine

Methionine

Ornithine

Phenylalanine

Proline

Sarcosine

Serine

Taurine

Threonine

Tryptophan

Tyrosine

Valine

Cystine

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes quantitation of the following amino acids: taurine, threonine, serine, asparagine, hydroxyproline, glutamic acid, glutamine, aspartic acid, ethanolamine, sarcosine, proline, glycine, alanine, citrulline, alpha-aminoadipic acid, alpha-amino-n-butyric acid, valine, cystine, cystathionine, methionine, isoleucine, leucine, tyrosine, phenylalanine, beta-alanine, beta-aminoisobutyric acid, ornithine, lysine, 1-methylhistidine, histidine, 3-methylhistidine, argininosuccinic acid, allo-isoleucine, homocitrulline, gamma-amino-n-butyric acid, hydroxylysine, tryptophan, and arginine.

Specimen Type
Describes the specimen type validated for testing

Urine

Additional Testing Requirements

Not all patients with homocystinuria will be detected by this assay. If homocystinuria is a concern, order CMMPP / Cobalamin, Methionine, and Methylmalonic Acid Pathways, Plasma or HCYSP / Homocysteine, Total, Plasma or HCYSS / Homocysteine, Total, Serum in tandem with this test.

Necessary Information

1. Patient's age is required.

2. Include family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.

3. If prolidase deficiency is a concern, indicate on the amino acid order "Pretreat with acid hydrolysis prior to analysis". The acid hydrolysis will break up in vitro proline and hydroxyproline containing dipeptides, which are cleaved in vivo by prolidase.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Supplies: Urine Tubes, 10 mL (T068)

Specimen Volume: 2 mL

Collection Instructions: Collect a random urine specimen.

Forms

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.

1 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Urine Frozen (preferred) 70 days
Refrigerated 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with possible inborn errors of metabolism using random urine specimens

 

May aid in evaluation of endocrine disorders, liver diseases, muscle diseases, neoplastic diseases, neurological disorders, nutritional disturbances, kidney failure, and burns

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes quantitation of the following amino acids: taurine, threonine, serine, asparagine, hydroxyproline, glutamic acid, glutamine, aspartic acid, ethanolamine, sarcosine, proline, glycine, alanine, citrulline, alpha-aminoadipic acid, alpha-amino-n-butyric acid, valine, cystine, cystathionine, methionine, isoleucine, leucine, tyrosine, phenylalanine, beta-alanine, beta-aminoisobutyric acid, ornithine, lysine, 1-methylhistidine, histidine, 3-methylhistidine, argininosuccinic acid, allo-isoleucine, homocitrulline, gamma-amino-n-butyric acid, hydroxylysine, tryptophan, and arginine.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Amino acids are the basic structural units that comprise proteins and are found throughout the body. Many inborn errors of amino acid metabolism that affect amino acid transport or metabolism have been identified, such as phenylketonuria and tyrosinemia. Amino acid disorders can manifest at any age, but most become evident in infancy or early childhood. These disorders result in the accumulation or the deficiency of 1 or more amino acids in biological fluids, which leads to the clinical signs and symptoms of the specific amino acid disorder.

 

The clinical presentation is dependent upon the specific amino acid disorder. In general, affected patients may experience failure to thrive, neurologic symptoms, digestive problems, dermatologic findings, and physical and cognitive delays. If not diagnosed and treated promptly, amino acid disorders can result in intellectual disabilities and, possibly, death.

 

In addition, amino acid analysis may have clinical importance in the evaluation of several acquired conditions including endocrine disorders, liver diseases, muscle diseases, neoplastic diseases, neurological disorders, nutritional disturbances, kidney failure, and burns. General elevations in urine amino acid levels, called aminoaciduria, can be seen in disorders with amino acid transport defects, such as lysinuric protein intolerance and Hartnup disease, as well as in conditions with renal tubular dysfunction including Lowe syndrome and Dent disease.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Amino Acid

Age groups

< 2 months

2-35 months

3-6 years

7-17 years

> or =18 years

Taurine

Tau

<9026

<5604

<3680

<3954

<2134

Asparagine

Asn

<687

<1159

<238

<322

<204

Serine

Ser

<3202

<2741

<1386

<1116

<658

Hydroxyproline

Hyp

<2254

<1775

<89

<42

<48

Glycine

Gly

<13336

<9872

<4997

<4467

<4068

Glutamine

Gln

<2931

<3681

<1124

<1038

<764

Aspartic Acid

Asp

<290

<72

<46

<13

<12

Ethanolamine

EtN

<1589

<1765

<776

<536

<500

Histidine

His

<3806

<4578

<2596

<2294

<1508

Threonine

Thr

<1930

<1769

<496

<575

<384

Citrulline

Cit

<61

<67

<23

<17

<34

Sarcosine

Sar

<177

<52

<6

<10

<6

Beta-Alanine

bAla

<174

<79

<99

<139

<58

Alanine

Ala

<2856

<2360

<961

<794

<472

Glutamic Acid

Glu

<281

<210

<127

<63

<62

1-Methylhistidine

1MHis

<493

<470

<517

<453

<265

3-Methylhistidine

3MHis

<196

<662

<3346

<2027

<1920

Argininosuccinic Acid

Asa

<96

<103

<65

<57

<37

Homocitrulline

Hcit

<164

<169

<110

<107

<87

Arginine

Arg

<250

<147

<81

<42

<65

Alpha-aminoadipic Acid

Aad

<264

<397

<349

<138

<73

Gamma Amino-n-butyric Acid

GABA

<8

<14

<4

<3

<4

Beta-aminoisobutyric Acid

bAib

<2214

<2488

<840

<251

<265

Alpha-amino-n-butyric Acid

Abu

<58

<44

<37

<29

<19

Hydroxylysine

Hyl

<101

<87

<44

<22

<16

Proline

Pro

<1776

<1028

<29

<42

<98

Ornithine

Orn

<344

<238

<228

<291

<193

Cystathionine

Cth

<118

<53

<23

<24

<33

Cystine

Cys

<486

<285

<111

<84

<142

Lysine

Lys

<2217

<1321

<814

<463

<295

Methionine

Met

<76

<45

<24

<22

<15

Valine

Val

<308

<258

<119

<91

<73

Tyrosine

Tyr

<453

<603

<289

<371

<155

Isoleucine

Ile

<99

<131

<52

<29

<26

Leucine

Leu

<286

<215

<87

<70

<64

Phenylalanine

Phe

<342

<306

<178

<123

<98

Tryptophan

Trp

<241

<329

<222

<218

<140

Allo-isoleucine

AlloIle

<3

<6

<1

<2

<4

 

All results reported as nmol/mg creatinine.

Interpretation
Provides information to assist in interpretation of the test results

When no significant abnormalities are detected, a simple descriptive interpretation is provided. When abnormal results are detected, a detailed interpretation is given, including an overview of the results and of their significance, a correlation to available clinical information, elements of differential diagnosis, recommendations for additional biochemical testing and in vitro confirmatory studies (enzyme assay, molecular analysis), name and phone number of key contacts who may provide these studies, and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This assay does not measure total homocysteine, phosphoethanolamine, or imidodipeptides. Therefore, this assay should not be used as a test for homocystinuria, hypophosphatasia, and prolidase deficiency. See Additional Testing Requirements and Necessary Information for more information or contact a biochemical genetics counselor at 800-533-1710.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Part 8: Amino Acids. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA. eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill, 2019. Accessed October 24, 2024. Available at https://ommbid.mhmedical.com/book.aspx?bookID=2709#225069340

2. Pasquali M, Longo N. Amino acids. In: Blau N, Dionisi Vici C, Ferreira CR, Vianey-Saban C, van Karnebeek CDM, eds. Physician's Guide to the Diagnosis, Treatment and Follow-up of Inherited Metabolic Diseases. 2nd ed. Springer-Verlag; 2022:41-50

Method Description
Describes how the test is performed and provides a method-specific reference

Quantitative analysis of amino acids is performed by liquid chromatography-tandem mass spectrometry. Patient samples are combined with isotopically labeled internal standard. Following protein precipitation, the supernatant is subjected to hydrophilic-interaction liquid chromatography for the separation of isomers with MS/MS detection of the underivatized amino acids.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

3 to 5 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

2 weeks

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Mayo Clinic Laboratories - Rochester Main Campus
CLIA Number: 24D0404292

Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

82139

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
AAPD Amino Acids, QN, Random, U 35087-6
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
3452 Taurine 28595-7
3456 Asparagine 28603-9
3455 Serine 30058-2
3460 Glycine 30066-5
3457 Glutamine 30056-6
3477 Histidine 30047-5
3454 Threonine 30057-4
3459 Citrulline 30161-4
3472 Beta-alanine 28588-2
3461 Alanine 30068-1
3458 Glutamic Acid 30059-0
3476 1-Methylhistidine 28606-2
3478 3-Methylhistidine 28594-0
3480 Arginine 30062-4
3462 Alpha-aminoadipic Acid 28598-1
3473 Beta-aminoisobutyric Acid 28602-1
3463 Alpha-amino-n-butyric Acid 28590-8
3483 Proline 30067-3
3474 Ornithine 30049-1
3466 Cystathionine 28599-9
3465 Cystine 30065-7
3475 Lysine 30048-3
3467 Methionine 30063-2
3464 Valine 30064-0
3470 Tyrosine 30054-1
3468 Isoleucine 30052-5
3469 Leucine 30053-3
3471 Phenylalanine 30055-8
3481 Interpretation (AAPD) 49248-8
34477 Hydroxyproline 28601-3
34478 Aspartic Acid 30061-6
34479 Ethanolamine 28605-4
34480 Sarcosine 28610-4
34481 Argininosuccinic Acid 32229-7
34483 Homocitrulline 32248-7
34484 Gamma-amino-n-butyric Acid 28593-2
34485 Hydroxylysine 30050-9
34486 Tryptophan 28608-8
34487 Allo-isoleucine 73908-6
113130 Reviewed By 18771-6

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
Test Changes - Reference Value 2024-06-17

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