Amino Acid Screen, CSF AACSF

Synonyms

Allscripts (AEHR) Order Name

Amino Acids, CSF

Sunrise Clinical Manager (SCM) Order Name

Amino Acids, CSF

EPIC Order Name

CSF, Amino Acid Screen

Clinical Info

Includes quantitation of the following amino acids: phosphoserine, phosphoethanolamine, taurine, threonine, serine, hydroxyproline, asparagine, glutamic acid, 1-methylhistidine, 3-methylhistidine, argininosuccinic acid, carnosine, anserine, homocitrulline, alpha-aminoadipic acid, gamma-amino-n-butyric acid, beta-aminoisobutyric acid, alpha-amino-n-butyric acid, hydroxylysine, glutamine, aspartic acid, ethanolamine, proline, glycine, alanine, citrulline, sarcosine, beta-alanine, alpha-amino-n-butyric acid, valine, cystine, methionine, isoleucine, leucine, tyrosine, phenylalanine, ornithine, cystathionine, tryptophan, allo-isoleucine, lysine, histidine, and arginine.
Evaluating patients with possible inborn errors of amino acid metabolism, in particular nonketotic hyperglycinemia (glycine encephalopathy) and serine biosynthesis defects, especially when used in conjunction with concomitantly collected plasma specimens
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 and metabolism 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 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.

Cerebrospinal fluid (CSF) specimens are highly informative for a subset of these conditions, such as nonketotic hyperglycinemia and serine biosynthesis defects. CSF specimens are most informative when a plasma specimen is drawn at the same time and the ratio of the amino acid concentrations in CSF to plasma is calculated.

Specimen Type

CSF

Container

CSF Tube

Collection Instructions

Container/Tube: Sterile vial
Specimen Volume: 0.2 mL CSF (0.1 mL min)
Collection Instructions: Collect specimen from second collection vial.

Transport Instructions

Frozen

Specimen Stability

14 Days Frozen

Methodology

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Portions of this test are covered by patents held by Quest Diagnostics

Days Performed

TAT: 4-6 Days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT

82139
LOINC Code: 35507-3

PDM

5302890

Result Interpretation

Amino Acid

Age groups

< or =31 days

32 days-23 months

2-18 years

> or =19 years

Taurine (Tau)

8-28

4-13

4-10

3-9

Asparagine (Asn)

7-25

5-17

4-12

5-14

Serine (Ser)

43-127

37-87

22-57

18-58

Hydroxyproline (Hyp)

<12

<8

<3

<3

Glycine (Gly)

<60

<27

<20

<28

Glutamine (Gln)

447-1547

384-716

375-770

452-1283

Aspartic Acid (Asp)

<12

<12

<12

<12

Ethanolamine (EtN)

11-152

6-41

7-25

6-24

Histidine (His)

19-63

12-32

9-26

12-36

Threonine (Thr)

35-212

19-89

13-51

13-57

Citrulline (Cit)

<6

<5

<4

<4

Sarcosine (Sar)

<21

<21

<21

<21

Beta-alanine (bAla)

<17

<17

<17

<17

Alanine (Ala)

20-92

18-69

16-54

22-80

Glutamic Acid (Glu)

<12

<4

<3

<2

1-Methylhistidine (1MHis)

<5

<1

<1

<3

3-Methylhistidine (3MHis)

<4

<1

<3

<5

Argininosuccinic Acid (Asa)

<4

<4

<4

<4

Homocitrulline (Hcit)

<1

<1

<1

<1

Arginine (Arg)

7-37

11-36

13-30

14-32

Alpha-aminoadipic Acid (Aad)

<2

<2

<2

<2

Gamma-amino-n-butyric Acid (GABA)

<10

<10

<10

<10

Beta-aminoisobutyric Acid (bAib)

<1

<1

<1

<1

Alpha-amino-n-butyric Acid (Abu)

<21

<7

<5

<10

Hydroxylysine (Hyl)

<1

<1

<1

<1

Proline (Pro)

<14

<4

<4

<2

Ornithine (Orn)

<32

<15

<12

<15

Cystathionine (Cth)

<4

<1

<1

<2

Cystine (Cys)

<3

<3

<3

<3

Lysine (Lys)

16-67

17-41

13-45

23-54

Methionine (Met)

<19

<7

<5

<12

Valine (Val)

16-83

10-36

10-27

13-52

Tyrosine (Tyr)

<70

<22

<16

<65

Isoleucine (Ile)

2-30

2-14

3-11

3-17

Leucine (Leu)

14-72

9-25

8-23

10-53

Phenylalanine (Phe)

9-49

7-18

5-18

8-23

Tryptophan (Trp)

<14

<14

<14

<14

Allo-isoleucine (AlloIle)

<2

<2

<2

<2

 

All results reported in nmol/mL

 

Forms

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