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HelpTest Code HCYSP Homocysteine, Total, Plasma
Necessary Information
1. Patient's age and sex are required.
2. Biochemical Genetics Patient Information (T602) is recommended, but not required, for suspected cases of inherited disorders of methionine metabolism.
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Green top (sodium or lithium heparin)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Immediately place specimen on wet ice.
2. Within 4 hours of collection, centrifuge and aliquot plasma into a plastic vial.
3. If blood cannot be placed on wet ice immediately, then within 1 hour of collection, centrifuge and aliquot plasma into a plastic vial.
4. A refrigerated centrifuge is not required if the above time restrictions are met.
Useful For
An aid for screening patients suspected of having an inherited disorder of methionine metabolism including:
-Cystathionine beta-synthase deficiency (homocystinuria)
-Methylenetetrahydrofolate reductase deficiency and its thermolabile variants
-Methionine synthase deficiency
-Cobalamin (Cbl) metabolism
-Combined methyl-Cbl and adenosyl-Cbl deficiencies: Cbl C2, Cbl D2, and Cbl F3 deficiencies
-Methyl-Cbl specific deficiencies: Cbl D-Var1, Cbl E, and Cbl G deficiencies
-Transcobalamin II deficiency
-Adenosylhomocysteinase deficiency
-Glycine N-methyltransferase deficiency
-Methionine adenosyltransferase I/III deficiency
Screening and monitoring patients suspected of, or confirmed with, an inherited disorder of methionine metabolism using plasma specimens
Evaluating individuals with suspected deficiency of vitamin B12 or folate
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Homocysteine, Total, PSpecimen Type
Plasma EDTASpecimen Minimum Volume
0.3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Plasma EDTA | Refrigerated (preferred) | 28 days |
| Frozen | 309 days | |
| Ambient | 28 days |
Reject Due To
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Reference Values
|
Age |
Total homocysteine (nmol/mL) |
|
|
Female |
Male |
|
|
0-11 months |
3.1-8.3 |
3.2-9.7 |
|
12-23 months |
3.2-8.3 |
3.3-9.6 |
|
24-35 months |
3.2-8.2 |
3.3-9.6 |
|
3 years |
3.2-8.2 |
3.3-9.6 |
|
4 years |
3.3-8.2 |
3.4-9.5 |
|
5 years |
3.4-8.1 |
3.5-9.4 |
|
6 years |
3.5-8.1 |
3.6-9.4 |
|
7 years |
3.5-8.1 |
3.7-9.4 |
|
8 years |
3.6-8.2 |
3.8-9.3 |
|
9 years |
3.7-8.2 |
3.9-9.4 |
|
10 years |
3.8-8.3 |
4.1-9.4 |
|
11 years |
3.9-8.4 |
4.3-9.4 |
|
12 years |
3.9-8.6 |
4.4-9.5 |
|
13 years |
4.0-8.7 |
4.6-9.6 |
|
14 years |
4.1-8.8 |
4.8-9.7 |
|
15 years |
4.2-8.9 |
5.0-9.8 |
|
16 years |
4.2-9.1 |
5.2-9.9 |
|
17 years |
4.3-9.2 |
5.4-10.0 |
|
18 years |
4.3-9.3 |
5.6-10.1 |
|
19 years |
4.4-9.5 |
5.7-10.3 |
|
20 years |
4.4-9.6 |
5.9-10.5 |
|
21 years |
4.4-9.8 |
6.0-10.6 |
|
22 years |
4.4-9.9 |
6.1-10.8 |
|
23 years |
4.4-10.1 |
6.2-11.0 |
|
24 years |
4.4-10.3 |
6.2-11.1 |
|
25 years |
4.4-10.4 |
6.3-11.3 |
|
26 years |
4.4-10.6 |
6.3-11.4 |
|
27 years |
4.3-10.8 |
6.4-11.6 |
|
28 years |
4.3-11.0 |
6.4-11.7 |
|
29 years |
4.3-11.2 |
6.4-11.8 |
|
30 years |
4.3-11.4 |
6.4-11.9 |
|
31 years |
4.4-11.6 |
6.4-12.1 |
|
32 years |
4.4-11.8 |
6.4-12.2 |
|
33 years |
4.4-11.9 |
6.4-12.3 |
|
34 years |
4.5-12.1 |
6.4-12.4 |
|
35 years |
4.5-12.2 |
6.4-12.6 |
|
36 years |
4.6-12.4 |
6.4-12.8 |
|
37 years |
4.6-12.5 |
6.4-12.9 |
|
38 years |
4.7-12.7 |
6.4-13.1 |
|
39 years |
4.7-12.8 |
6.4-13.2 |
|
40 years |
4.8-13.0 |
6.5-13.4 |
|
41 years |
4.8-13.2 |
6.5-13.5 |
|
42 years |
4.8-13.4 |
6.5-13.7 |
|
43 years |
4.9-13.5 |
6.6-13.9 |
|
44 years |
4.9-13.7 |
6.6-14.0 |
|
45 years |
4.9-13.9 |
6.6-14.2 |
|
46 years |
4.9-14.0 |
6.7-14.4 |
|
47 years |
4.9-14.2 |
6.7-14.5 |
|
48 years |
5.0-14.3 |
6.8-14.7 |
|
49 years |
5.0-14.4 |
6.8-14.9 |
|
50 years |
5.0-14.5 |
6.8-15.0 |
|
51 years |
5.1-14.6 |
6.8-15.2 |
|
52 years |
5.1-14.7 |
6.9-15.4 |
|
53 years |
5.1-14.8 |
6.9-15.5 |
|
54 years |
5.2-14.9 |
6.9-15.6 |
|
55 years |
5.2-15.0 |
6.9-15.7 |
|
56 years |
5.3-15.0 |
6.9-15.8 |
|
57 years |
5.3-15.1 |
6.9-15.9 |
|
58 years |
5.3-15.2 |
6.9-16.0 |
|
59 years |
5.4-15.2 |
6.9-16.0 |
|
60 years |
5.4-15.3 |
6.9-16.1 |
|
61 years |
5.4-15.4 |
7.0-16.2 |
|
62 years |
5.5-15.4 |
7.0-16.2 |
|
63 years |
5.5-15.5 |
7.0-16.3 |
|
64 years |
5.6-15.5 |
7.1-16.3 |
|
65 years |
5.6-15.6 |
7.1-16.3 |
|
66 years |
5.7-15.6 |
7.1-16.3 |
|
67 years |
5.7-15.7 |
7.2-16.3 |
|
68 years |
5.8-15.7 |
7.2-16.3 |
|
69 years |
5.9-15.7 |
7.2-16.3 |
|
70 years |
6.0-15.8 |
7.3-16.3 |
|
71 years |
6.1-15.8 |
7.3-16.3 |
|
72 years |
6.2-15.8 |
7.3-16.3 |
|
73 years |
6.3-15.9 |
7.3-16.3 |
|
74 years |
6.4-15.9 |
7.3-16.3 |
|
75 years |
6.5-15.9 |
7.3-16.3 |
|
76 years |
6.6-15.9 |
7.3-16.3 |
|
77 years |
6.7-16.0 |
7.4-16.3 |
|
78 years |
6.8-16.0 |
7.4-16.3 |
|
79 years |
6.9-16.0 |
7.5-16.3 |
|
80 years |
7.0-16.0 |
7.5-16.3 |
|
81 years |
7.1-16.0 |
7.7-16.2 |
|
82 years |
7.2-16.0 |
7.8-16.2 |
|
83 years |
7.2-16.0 |
7.9-16.2 |
|
84 years |
7.3-16.0 |
8.0-16.2 |
|
85 years |
7.3-16.0 |
8.2-16.2 |
|
>85 years |
7.4-16.0 |
8.3-16.2 |
Day(s) Performed
Monday through Friday
Report Available
3 to 5 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
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
83090
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| HCYSP | Homocysteine, Total, P | 13965-9 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 80379 | Homocysteine, Total, P | 13965-9 |
Forms
1. Biochemical Genetics Patient Information (T602)
2. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.