Sign in →

Test ID: AAQP Amino Acids, Quantitative, Plasma

Reporting Name

Amino Acids, QN, P

Useful For

Evaluating patients with possible inborn errors of metabolism

 

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

Specimen Type

Plasma


Additional Testing Requirements


Not all patients with homocystinuria will be detected by this assay. If there is a concern for homocystinuria, please order HCYSU / Homocysteine, Total, Urine in tandem with amino acids.

Necessary Information


1. Patient's age is required.

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



Specimen Required


Patient Preparation

Fasting (overnight preferred, 4 hours minimum). Infants should be drawn just before next feeding (2-3 hours without TPN if possible).

 

Collection Container/Tube:

Preferred: Green top (sodium heparin)

Acceptable: EDTA, PST, lithium heparin

Submission Container/Tube: Plastic vial

Specimen Volume: 0.5 mL

Collection Instructions: Centrifuge within 4 hours if specimen is stored at refrigerated temperature and aliquot plasma. Send plasma frozen.


Specimen Minimum Volume

0.3 mL

Specimen Stability Information

Specimen Type Temperature Time
Plasma Frozen 14 days

Reference Values

Plasma Amino Acid Reference Values (nmol/mL)

Age Groups

<24 Months (n=191)

2-17 Years (n=441)

≥18 Years (n=148)

Phosphoserine (PSer)

<109

<95

<18

Phosphoethanolamine (PEtN)

<6

<5

<12

Taurine (Tau)

37-177

38-153

42-156

Asparagine (Asn)

25-91

29-87

37-92

Serine (Ser)

69-271

71-208

63-187

Hydroxyproline (Hyp)

8-61

7-35

4-29

Glycine (Gly)

111-426

149-417

126-490

Glutamine (Gln)

316-1020

329-976

371-957

Aspartic Acid (Asp)

2-20

<11

<7

Ethanolamine (EtN)

<70

<64

<67

Histidine (His)

10-116

12-132

39-123

Threonine (Thr)

47-237

58-195

85-231

Citrulline (Cit)

9-38

11-45

17-46

Sarcosine (Sar)

<5

<5

<5

b-Alanine (bAla)

<28

<27

<29

Alanine (Ala)

139-474

144-557

200-579

Glutamic Acid (Glu)

31-202

22-131

13-113

1-Methylhistidine (1MHis)

<11

<20

<28

3-Methylhistidine (3MHis)

<1

<1

2-9

Argininosuccinic Acid (Asa)

<2

<2

<2

Carnosine (Car)

<13

<1

<1

Anserine (Ans)

<1

<1

<1

Homocitruline (Hcit)

<5

<2

<2

Arginine (Arg)

29-134

31-132

32-120

a-Aminoadipic Acid (Aad)

<4

<3

<3

g-Amino-n-butyric Acid (GABA)

<4

<3

<2

b-Aminoisobutyric Acid (bAib)

<9

<5

<5

a-Amino-n-butyric Acid (Abu)

7-28

7-31

9-37

Hydroxylysine (Hyl)

<4

<3

<2

Proline (Pro)

85-303

80-357

97-368

Ornithine (Orn)

20-130

22-97

38-130

Cystathionine (Cth)

<2

<2

<5

Cystine (Cys)

2-32

2-36

3-95

Lysine (Lys)

49-204

59-240

103-255

Methionine (Met)

11-35

11-37

4-44

Valine (Val)

83-300

106-320

136-309

Tyrosine (Tyr)

26-115

31-106

31-90

Isoleucine (IIe)

31-105

30-111

36-107

Leucine (Leu)

48-175

51-196

68-183

Phenylalanine (Phe)

28-80

30-95

35-80

Tryptophan (Trp)

17-75

23-80

29-77

Alloisoleucine (Allolle)

<2

<3

<5

Day(s) and Time(s) Performed

Monday through Friday; 8 a.m.

Test Classification

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

CPT Code Information

82139

LOINC Code Information

Test ID Test Order Name Order LOINC Value
AAQP Amino Acids, QN, P In Process

 

Result ID Test Result Name Result LOINC Value
34449 Phosphoserine 20654-0
34457 Phosphoethanolamine 26612-2
3512 Taurine 20657-3
3517 Asparagine 20638-3
3516 Serine 20656-5
34458 Hydroxyproline 20647-4
3522 Glycine 20644-1
3518 Glutamine 20643-3
34459 Aspartic Acid 20639-1
34460 Ethanolamine 26608-0
3535 Histidine 20645-8
3515 Threonine 20658-1
3521 Citrulline 20640-9
34461 Sarcosine 26613-0
3532 Beta-Alanine 26604-9
3523 Alanine 20636-7
3520 Glutamic Acid 20642-5
34453 1-Methylhistidine 20633-4
34454 3-Methylhistidine 20635-9
32341 Argininosuccinic Acid 32227-1
34455 Carnosine 26606-4
34462 Anserine 26599-1
34456 Homocitrulline 55876-7
3536 Arginine 20637-5
34450 Alpha-aminoadipic Acid 26600-7
34463 Gamma-amino-n-butyric Acid 26609-8
34452 Beta-aminoisobutyric Acid 26605-6
3524 Alpha-amino-n-butyric Acid 20634-2
34464 Hydroxylysine 26610-6
3519 Proline 20655-7
3533 Ornithine 20652-4
34451 Cystathionine 26607-2
3526 Cystine 22672-0
3534 Lysine 20650-8
3527 Methionine 20651-6
3525 Valine 20661-5
3530 Tyrosine 20660-7
3528 Isoleucine 20648-2
3529 Leucine 20649-0
3531 Phenylalanine 14875-9
34465 Tryptophan 20659-9
32347 Allo-isoleucine 22670-4
3570 Interpretation (AAQP) 49247-0

Clinical Information

Amino acids are the basic structural units that comprise proteins and are found throughout the body. Many inborn errors of amino acid metabolism, including phenylketonuria and tyrosinemia, have been identified. 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 particular 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 mental retardation and death.

 

Treatment for amino acid disorders includes very specific dietary modifications. Nonessential amino acids are synthesized by the body, while essential amino acids are not and must be obtained through an individual's diet. Therapeutic diets are coordinated and closely monitored by a dietician and/or physician. They are structured to provide the necessary balance of amino acids with particular attention to essential amino acids and those that accumulate in a particular disorder. Patients must pay close attention to the protein content in their diet and generally need to supplement with medical formulas and foods. Dietary compliance is monitored by periodic analysis of plasma amino acids.

 

In addition, plasma 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, renal failure, and burns.

Interpretation

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 at Mayo Clinic or elsewhere, and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.

Clinical Reference

Scriver's The Online Metabolic and Molecular Bases of Inherited Disease (OMMBID). Part 8 Amino Acids. Accessed July 6, 2016. Available at http://ommbid.mhmedical.com/book.aspx?bookid=971

Analytic Time

3 days (not reported on Saturday or Sunday)

Testing Algorithm

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

Method Name

Quantitative Analysis by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Mayo Medical Laboratories | Genetics and Pharmacogenomics Catalog Additional Information:

mml-biochemical