Test Id : CMMPP
Cobalamin, Methionine, and Methylmalonic Acid Pathways, Plasma
Useful For
Suggests clinical disorders or settings where the test may be helpful
Screening and monitoring patients suspected of or confirmed with an inherited disorder of methionine, cobalamin, or propionate metabolism using plasma specimens
Evaluating individuals with suspected deficiency of vitamin B12
Method Name
A short description of the method used to perform the test
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
CBS deficiency
Cobalamin C deficiency
Cobalamin D deficiency
Cobalamin E deficiency
Cobalamin F deficiency
Cobalamin G deficiency
Cobalamin J deficiency
Cobalamin X deficiency
Hypermethioninemia
MAT I/III Deficiency
MAT Deficiency
Hypermethioninemia, isolated persistent
MMACHC
MMADHC
Combined Methylmalonic acidemia and homocystinuria
Homocysteine
Methylmalonic acid
Methylcitric acid
HCY
MMA
PA
Methylenetetrahydrofolate reductase (MTHFR) deficiency
Transcobalamin II deficiency:
Adenosylhomocysteinase (AHCY) deficiency
Glycine N-methyltransferase (GNMT) deficiency
Specimen Type
Describes the specimen type validated for testing
Plasma
Necessary Information
Patient's age and sex are required.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
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 ice.
2. Within 4 hours of collection, centrifuge and aliquot plasma into plastic vial.
3. If blood cannot be placed on wet ice immediately, centrifuge and aliquot plasma into plastic vial within 1 hour of collection.
4. A refrigerated centrifuge is not required if the above time restrictions are met.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
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.
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.
0.3 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
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 |
|---|---|---|---|
| Plasma | Refrigerated (preferred) | 28 days | |
| Ambient | 28 days | ||
| Frozen | 309 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Screening and monitoring patients suspected of or confirmed with an inherited disorder of methionine, cobalamin, or propionate metabolism using plasma specimens
Evaluating individuals with suspected deficiency of vitamin B12
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Homocysteine, methylmalonic acid (MMA), methylcitric acid, methionine, cysteine, and cystathionine can be used to evaluate patients for inborn errors of methionine, cobalamin, and propionate metabolism. Homocysteine is an intermediary in the sulfur-amino acid metabolism pathways, linking the methionine cycle to the folate cycle.
Inborn errors of metabolism that lead to homocysteinemia or homocystinuria include cystathionine beta-synthase deficiency (homocystinuria) and various defects of methionine remethylation.
Homocystinuria is an autosomal recessive disorder caused by a deficiency of the enzyme cystathionine beta-synthase. The incidence of homocystinuria is approximately 1 in 200,000 to 335,000 live births. Classical homocystinuria is characterized by a normal presentation at birth followed by failure to thrive and developmental delay. Untreated homocystinuria can lead to ophthalmological problems, developmental delay, seizures, thromboembolic episodes, and skeletal abnormalities. The biochemical phenotype is characterized by increased plasma concentrations of methionine and homocysteine along with decreased concentrations of cystine.
Elevated levels of MMA result from inherited defects of enzymes involved in MMA metabolism or inherited or acquired deficiencies of vitamin B12.
Enzymatic deficiencies of propionyl-CoA carboxylase and methylmalonyl-CoA mutase are associated with propionic academia (PA) and methylmalonic acidemia mut(0/-) type (MMAmut), respectively. The clinical phenotype includes vomiting, hypotonia, lethargy, apnea, hypothermia, and coma. The biochemical phenotype for MMAmut includes elevations of propionyl carnitine, methylmalonic acid, and methylcitric acid. Patients with PA will have elevations of propionyl carnitine and methylcitric acid with normal MMA concentrations as the enzymatic defect is upstream of methylmalonic-CoA mutase.
Inherited conditions of cobalamin (Cbl) absorption and transport are caused by variants in several genes encoding Cbl binding factors and transmembrane transporters and receptors. In addition, inside the cell, Cbl undergoes several steps of modification until it reaches a divergent point beyond which 2 separate paths lead to the formation of the 2 active components of this cofactor: adenosylcobalamin (AdoCbl), a cofactor for methylmalonyl-CoA mutase; and methylcobalamin (MeCbl), a cofactor for methionine synthase, remethylating homocysteine to methionine.
Defects of AdoCbl and MeCbl metabolism after the point where the synthetic pathways separate lead to isolated deficiencies of methylmalonyl-CoA mutase (elevations of propionyl carnitine, MMA, and methylcitric acid) or methionine synthase (elevated homocysteine with low/low normal methionine) respectively. Defects prior to this point are associated with deficiencies of both enzymes and lead to elevation of all markers (propionyl carnitine, MMA, methylcitric acid, and homocysteine).
Acquired cobalamin (vitamin B12) deficiency can be a result of pernicious anemia, vegan diet, malabsorption, and decreased intrinsic factor excretion (secondary to gastrectomy) and can be distinguished from most inherited defects (particularly intracellular deficiencies) with the identification of decreased levels of vitamin B12. Older adult patients with acquired cobalamin deficiency may present with megaloblastic anemia, peripheral neuropathy, ataxia, loss of position and vibration senses, memory impairment, depression, and dementia in the absence of anemia. Other conditions such as kidney insufficiency, hypovolemia, and bacterial overgrowth of the small intestine also contribute to the possible causes of mild methylmalonic acidemia and aciduria. Additional testing with homocysteine and MMA determinations may help distinguish between vitamin B12 and folate deficiency states.
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.
| Age | Total homocysteine | Methylmalonic acid (nmol/mL) | 2-Methylcitric | Total cysteine | Methionine (nmol/mL) | Cystathionine | ||
| Female | Male | Female | Male | |||||
| 0-11 months | 3.1-8.3 | 3.2-9.7 | 0.08-0.32 | 0.02-0.35 | 142.8-258.8 | 14.7-43.1 | 14.5-42.3 | 0.07-0.38 |
| 12-23 months | 3.2-8.3 | 3.3-9.6 | 0.08-0.31 | 0.02-0.35 | 143.7-258.7 | 14.7-43.1 | 14.5-42.2 | 0.07-0.38 |
| 24-35 months | 3.2-8.2 | 3.3-9.6 | 0.08-0.31 | 0.02-0.35 | 144.8-258.6 | 14.7-43.0 | 14.5-42.1 | 0.07-0.38 |
| 3 years | 3.2-8.2 | 3.3-9.6 | 0.08-0.31 | 0.02-0.35 | 146.0-258.5 | 14.7-43.0 | 14.5-42.0 | 0.07-0.38 |
| 4 years | 3.3-8.2 | 3.4-9.5 | 0.08-0.30 | 0.02-0.35 | 148.2-258.4 | 14.7-42.8 | 14.5-41.8 | 0.07-0.38 |
| 5 years | 3.4-8.1 | 3.5-9.4 | 0.08-0.30 | 0.02-0.35 | 150.6-258.3 | 14.8-42.7 | 14.5-41.6 | 0.07-0.38 |
| 6 years | 3.5-8.1 | 3.6-9.4 | 0.08-0.29 | 0.02-0.35 | 153.2-258.3 | 14.8-42.5 | 14.5-41.4 | 0.07-0.38 |
| 7 years | 3.5-8.1 | 3.7-9.4 | 0.08-0.29 | 0.02-0.35 | 155.8-258.4 | 14.8-42.2 | 14.5-41.1 | 0.07-0.38 |
| 8 years | 3.6-8.2 | 3.8-9.3 | 0.08-0.28 | 0.02-0.35 | 158.5-258.7 | 14.9-42.0 | 14.6-40.9 | 0.07-0.37 |
| 9 years | 3.7-8.2 | 3.9-9.4 | 0.09-0.28 | 0.02-0.35 | 161.0-259.1 | 14.9-41.7 | 14.6-40.7 | 0.07-0.37 |
| 10 years | 3.8-8.3 | 4.1-9.4 | 0.09-0.28 | 0.02-0.35 | 163.5-259.7 | 15.0-41.4 | 14.7-40.6 | 0.07-0.37 |
| 11 years | 3.9-8.4 | 4.3-9.4 | 0.09-0.28 | 0.02-0.35 | 165.9-260.5 | 15.1-41.0 | 14.8-40.4 | 0.07-0.37 |
| 12 years | 3.9-8.6 | 4.4-9.5 | 0.09-0.27 | 0.02-0.35 | 168.4-261.4 | 15.1-40.7 | 14.9-40.3 | 0.07-0.37 |
| 13 years | 4.0-8.7 | 4.6-9.6 | 0.09-0.27 | 0.02-0.35 | 170.9-262.4 | 15.2-40.3 | 15.1-40.1 | 0.07-0.36 |
| 14 years | 4.1-8.8 | 4.8-9.7 | 0.09-0.27 | 0.02-0.35 | 173.6-263.6 | 15.3-39.9 | 15.3-40.0 | 0.07-0.36 |
| 15 years | 4.2-8.9 | 5.0-9.8 | 0.09-0.27 | 0.02-0.35 | 176.4-264.7 | 15.4-39.5 | 15.5-39.9 | 0.07-0.36 |
| 16 years | 4.2-9.1 | 5.2-9.9 | 0.09-0.27 | 0.02-0.35 | 179.3-265.9 | 15.5-39.1 | 15.8-39.7 | 0.07-0.35 |
| 17 years | 4.3-9.2 | 5.4-10.0 | 0.09-0.27 | 0.02-0.35 | 182.2-267.1 | 15.6-38.7 | 16.1-39.6 | 0.07-0.35 |
| 18 years | 4.3-9.3 | 5.6-10.1 | 0.08-0.27 | 0.02-0.35 | 184.9-268.3 | 15.7-38.2 | 16.4-39.4 | 0.07-0.35 |
| 19 years | 4.4-9.5 | 5.7-10.3 | 0.08-0.26 | 0.02-0.35 | 187.4-269.4 | 15.7-37.8 | 16.7-39.3 | 0.07-0.34 |
| 20 years | 4.4-9.6 | 5.9-10.5 | 0.08-0.26 | 0.02-0.35 | 189.5-270.5 | 15.8-37.3 | 17.0-39.1 | 0.07-0.34 |
| 21 years | 4.4-9.8 | 6.0-10.6 | 0.08-0.26 | 0.02-0.35 | 191.2-271.7 | 15.9-36.8 | 17.3-38.9 | 0.07-0.33 |
| 22 years | 4.4-9.9 | 6.1-10.8 | 0.08-0.27 | 0.02-0.35 | 192.5-272.8 | 15.9-36.3 | 17.6-38.7 | 0.07-0.33 |
| 23 years | 4.4-10.1 | 6.2-11.0 | 0.08-0.27 | 0.02-0.35 | 193.5-274.1 | 15.9-35.8 | 17.9-38.5 | 0.07-0.33 |
| 24 years | 4.4-10.3 | 6.2-11.1 | 0.08-0.27 | 0.02-0.35 | 194.2-275.4 | 15.9-35.3 | 18.1-38.3 | 0.07-0.32 |
| 25 years | 4.4-10.4 | 6.3-11.3 | 0.08-0.28 | 0.02-0.35 | 194.8-277.0 | 15.9-34.8 | 18.2-38.1 | 0.07-0.32 |
| 26 years | 4.4-10.6 | 6.3-11.4 | 0.08-0.28 | 0.02-0.35 | 195.3-278.6 | 15.9-34.3 | 18.4-37.9 | 0.07-0.32 |
| 27 years | 4.3-10.8 | 6.4-11.6 | 0.08-0.28 | 0.02-0.35 | 196.0-280.5 | 16.0-33.8 | 18.5-37.7 | 0.07-0.31 |
| 28 years | 4.3-11.0 | 6.4-11.7 | 0.08-0.29 | 0.02-0.35 | 196.7-282.4 | 16.0-33.4 | 18.7-37.5 | 0.07-0.31 |
| 29 years | 4.3-11.2 | 6.4-11.8 | 0.08-0.29 | 0.02-0.35 | 197.7-284.3 | 16.0-33.0 | 18.8-37.3 | 0.07-0.31 |
| 30 years | 4.3-11.4 | 6.4-11.9 | 0.08-0.30 | 0.02-0.35 | 198.8-286.3 | 16.1- 32.6 | 18.9-37.1 | 0.07-0.30 |
| 31 years | 4.4-11.6 | 6.4-12.1 | 0.08-0.30 | 0.02-0.35 | 200.2-288.2 | 16.1-32.2 | 19.0-36.9 | 0.07-0.30 |
| 32 years | 4.4-11.8 | 6.4-12.2 | 0.08-0.31 | 0.02-0.35 | 201.7-290.0 | 16.1-31.8 | 19.1-36.7 | 0.07-0.30 |
| 33 years | 4.4-11.9 | 6.4-12.3 | 0.08-0.31 | 0.02-0.35 | 203.4-291.5 | 16.1-31.5 | 19.2-36.5 | 0.07-0.29 |
| 34 years | 4.5-12.1 | 6.4-12.4 | 0.08-0.31 | 0.02-0.35 | 205.2-292.9 | 16.1-31.2 | 19.3-36.3 | 0.07-0.29 |
| 35 years | 4.5-12.2 | 6.4-12.6 | 0.08-0.32 | 0.02-0.35 | 207.2-294.1 | 16.1-30.8 | 19.4-36.1 | 0.07-0.28 |
| 36 years | 4.6-12.4 | 6.4-12.8 | 0.08-0.32 | 0.02-0.35 | 209.3-295.1 | 16.1-30.5 | 19.5-35.9 | 0.07-0.28 |
| 37 years | 4.6-12.5 | 6.4-12.9 | 0.08-0.33 | 0.02-0.35 | 211.5-296.0 | 16.1-30.2 | 19.6-35.6 | 0.07-0.27 |
| 38 years | 4.7-12.7 | 6.4-13.1 | 0.08-0.33 | 0.02-0.35 | 213.8-296.9 | 16.1-29.9 | 19.7-35.4 | 0.07-0.27 |
| 39 years | 4.7-12.8 | 6.4-13.2 | 0.08-0.34 | 0.02-0.35 | 216.3-297.7 | 16.1-29.7 | 19.8-35.2 | 0.07-0.27 |
| 40 years | 4.8-13.0 | 6.5-13.4 | 0.08-0.34 | 0.02-0.35 | 218.9-298.7 | 16.1-29.4 | 19.9-35.0 | 0.07-0.27 |
| 41 years | 4.8-13.2 | 6.5-13.5 | 0.08-0.35 | 0.02-0.35 | 221.6-299.7 | 16.1-29.2 | 20.0-34.8 | 0.07-0.27 |
| 42 years | 4.8-13.4 | 6.5-13.7 | 0.08-0.36 | 0.02-0.35 | 224.3-300.8 | 16.2-29.0 | 20.1-34.6 | 0.07-0.26 |
| 43 years | 4.9-13.5 | 6.6-13.9 | 0.08-0.36 | 0.02-0.35 | 227.0-302.0 | 16.2-28.8 | 20.2-34.4 | 0.07-0.26 |
| 44 years | 4.9-13.7 | 6.6-14.0 | 0.08-0.37 | 0.02-0.35 | 229.8-303.5 | 16.3-28.6 | 20.3-34.2 | 0.07-0.26 |
| 45 years | 4.9-13.9 | 6.6-14.2 | 0.08-0.38 | 0.02-0.35 | 232.6-305.2 | 16.3-28.5 | 20.3-34.0 | 0.07-0.26 |
| 46 years | 4.9-14.0 | 6.7-14.4 | 0.08-0.38 | 0.02-0.35 | 235.3-307.3 | 16.4-28.4 | 20.4-33.8 | 0.07-0.26 |
| 47 years | 4.9-14.2 | 6.7-14.5 | 0.08-0.39 | 0.02-0.35 | 238.0-309.7 | 16.4-28.2 | 20.4-33.6 | 0.07-0.26 |
| 48 years | 5.0-14.3 | 6.8-14.7 | 0.08-0.39 | 0.02-0.35 | 240.8-312.6 | 16.5-28.1 | 20.5-33.3 | 0.07-0.26 |
| 49 years | 5.0-14.4 | 6.8-14.9 | 0.08-0.40 | 0.02-0.35 | 243.5-315.9 | 16.5-28.0 | 20.5-33.1 | 0.07-0.26 |
| 50 years | 5.0-14.5 | 6.8-15.0 | 0.08-0.40 | 0.02-0.35 | 246.2-319.7 | 16.5-27.9 | 20.6-32.8 | 0.07-0.26 |
| 51 years | 5.1-14.6 | 6.8-15.2 | 0.08-0.41 | 0.02-0.35 | 248.9-323.8 | 16.5-27.8 | 20.6-32.5 | 0.07-0.26 |
| 52 years | 5.1-14.7 | 6.9-15.4 | 0.08-0.41 | 0.02-0.35 | 251.5-328.1 | 16.5-27.6 | 20.7-32.3 | 0.07-0.26 |
| 53 years | 5.1-14.8 | 6.9-15.5 | 0.08-0.42 | 0.02-0.35 | 254.0-332.4 | 16.5-27.5 | 20.8-32.1 | 0.07-0.26 |
| 54 years | 5.2-14.9 | 6.9-15.6 | 0.08-0.42 | 0.02-0.35 | 256.4-336.5 | 16.5-27.4 | 21.0-31.9 | 0.07-0.25 |
| 55 years | 5.2-15.0 | 6.9-15.7 | 0.08-0.43 | 0.02-0.35 | 258.6-340.2 | 16.5-27.3 | 21.1-31.7 | 0.07-0.25 |
| 56 years | 5.3-15.0 | 6.9-15.8 | 0.08-0.43 | 0.02-0.35 | 260.6-343.6 | 16.6-27.2 | 21.2-31.5 | 0.07-0.25 |
| 57 years | 5.3-15.1 | 6.9-15.9 | 0.08-0.44 | 0.02-0.35 | 262.5-346.5 | 16.6-27.1 | 21.2-31.3 | 0.07-0.25 |
| 58 years | 5.3-15.2 | 6.9-16.0 | 0.08-0.44 | 0.02-0.35 | 264.3-349.0 | 16.6-27.1 | 21.3-31.0 | 0.07-0.25 |
| 59 years | 5.4-15.2 | 6.9-16.0 | 0.08-0.44 | 0.02-0.35 | 266.2-351.1 | 16.7-27.1 | 21.3-30.8 | 0.07-0.25 |
| 60 years | 5.4-15.3 | 6.9-16.1 | 0.08-0.45 | 0.02-0.35 | 268.3-353.1 | 16.8-27.1 | 21.3-30.6 | 0.07-0.25 |
| 61 years | 5.4-15.4 | 7.0-16.2 | 0.09-0.45 | 0.02-0.35 | 270.8-355.1 | 16.9-27.2 | 21.3-30.3 | 0.07-0.25 |
| 62 years | 5.5-15.4 | 7.0-16.2 | 0.09-0.46 | 0.02-0.35 | 273.8-357.3 | 17.0-27.2 | 21.2-30.0 | 0.08-0.25 |
| 63 years | 5.5-15.5 | 7.0-16.3 | 0.09-0.46 | 0.02-0.35 | 277.5-359.7 | 17.1-27.3 | 21.2-29.8 | 0.08-0.25 |
| 64 years | 5.6-15.5 | 7.1-16.3 | 0.09-0.46 | 0.02-0.35 | 281.9-362.3 | 17.2-27.4 | 21.1-29.5 | 0.08-0.25 |
| 65 years | 5.6-15.6 | 7.1-16.3 | 0.09-0.47 | 0.02-0.35 | 286.9-365.2 | 17.3-27.6 | 21.1-29.2 | 0.08-0.25 |
| 66 years | 5.7-15.6 | 7.1-16.3 | 0.09-0.47 | 0.02-0.35 | 292.4-368.3 | 17.4-27.7 | 21.1-29.0 | 0.08-0.25 |
| 67 years | 5.7-15.7 | 7.2-16.3 | 0.09-0.47 | 0.02-0.35 | 298.1-371.6 | 17.5-27.8 | 21.0-28.7 | 0.09-0.25 |
| 68 years | 5.8-15.7 | 7.2-16.3 | 0.09-0.47 | 0.02-0.35 | 303.6-374.8 | 17.7-27.9 | 21.0-28.5 | 0.09-0.25 |
| 69 years | 5.9-15.7 | 7.2-16.3 | 0.09-0.47 | 0.02-0.35 | 308.7-377.8 | 17.8-28.0 | 21.0-28.4 | 0.09-0.25 |
| 70 years | 6.0-15.8 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 313.1-380.7 | 18.0-28.1 | 21.0-28.3 | 0.09-0.25 |
| 71 years | 6.1-15.8 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 316.5-383.2 | 18.1-28.2 | 20.9-28.2 | 0.09-0.25 |
| 72 years | 6.2-15.8 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 318.9-385.3 | 18.3-28.3 | 20.9-28.0 | 0.09-0.25 |
| 73 years | 6.3-15.9 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 320.1-387.0 | 18.5-28.4 | 20.8-27.9 | 0.10-0.26 |
| 74 years | 6.4-15.9 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 320.6-388.3 | 18.8-28.5 | 20.8-27.8 | 0.10-0.26 |
| 75 years | 6.5-15.9 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 320.3-389.3 | 19.1-28.5 | 20.8-27.7 | 0.10-0.26 |
| 76 years | 6.6-15.9 | 7.3-16.3 | 0.09-0.48 | 0.02-0.35 | 319.6-389.9 | 19.3-28.6 | 20.8-27.5 | 0.10-0.26 |
| 77 years | 6.7-16.0 | 7.4-16.3 | 0.10-0.48 | 0.02-0.35 | 319.1-390.2 | 19.6-28.6 | 20.9-27.4 | 0.10-0.26 |
| 78 years | 6.8-16.0 | 7.4-16.3 | 0.10-0.48 | 0.02-0.35 | 318.5-390.5 | 20.0-28.7 | 20.9-27.2 | 0.11-0.26 |
| 79 years | 6.9-16.0 | 7.5-16.3 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 80 years | 7.0-16.0 | 7.5-16.3 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 81 years | 7.1-16.0 | 7.7-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 82 years | 7.2-16.0 | 7.8-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 83 years | 7.2-16.0 | 7.9-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 84 years | 7.3-16.0 | 8.0-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| 85 years | 7.3-16.0 | 8.2-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
| >85 years | 7.4-16.0 | 8.3-16.2 | 0.10-0.48 | 0.02-0.35 | 317.9-390.6 | 20.3-28.7 | 21.0-27.1 | 0.11-0.26 |
Interpretation
Provides information to assist in interpretation of the test results
An interpretive report will be 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 (complementation studies, molecular analysis), and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.
Abnormal results are not sufficient to conclusively establish a diagnosis of a particular disease. To verify a preliminary diagnosis based on the analysis, independent biochemical (eg, complementation studies) or molecular genetic analyses are required.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Normal levels may be seen in patients undergoing treatment.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Turgeon CT, Magera MJ, Cuthbert CD, et al. Determination of total homocysteine, methylmalonic acid, and 2-methylcitric acid in dried blood spots by tandem mass spectrometry. Clin Chem. 2010;56(11):1686-1695
2. Tortorelli S, Turgeon CT, Lim JS, et al. Two-tier approach to the newborn screening of methylenetetrahydrofolate reductase deficiency and other remethylation disorders with tandem mass spectrometry. J Pediatr. 2010;157(2):271-275
3. Huemer M, Diodato D, Schwahn B, et al. Guidelines for diagnosis and management of the cobalamin-related remethylation disorders cblC, cblD, cblE, cblF, cblG, cblJ and MTHFR deficiency. J Inherit Metab Dis. 2017;40(1):21-48
4. Baric I, Staufner C, Augoustides-Savvopoulou P, Chien YH, Dobbelaere D, Grunert SC. Consensus recommendations for the diagnosis, treatment and follow-up of inherited methylation disorders. J Inherit Metab Dis. 2017;40(1):5-20
5. Morris AA, Kozich V, Santra S, et al. Guidelines for the diagnosis and management of cystathionine beta-synthase deficiency. J Inherit Metab Dis. 2017;40(1):49-74
6. Sloan JS, Carrillo N, Adams D, Venditti CP. Disorders of intracellular cobalamin metabolism. In: Adam MP, Feldman J, Mirzaa GM, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2008. Updated December 16, 2021. Accessed November 29, 2024. Available at www.ncbi.nlm.nih.gov/books/NBK1328/
7. Langan RC, Goodbred AJ. Vitamin B12 deficiency: Recognition and management. Am Fam Physician. 2017;96(6):384-389
Method Description
Describes how the test is performed and provides a method-specific reference
Total homocysteine, total cysteine, 2-methylcitric acid, methionine, cystathionine and methylmalonic acid are measured by stabile isotope dilution microflow liquid chromatography tandem mass spectrometry.(Unpublished Mayo method)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
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, Wednesday, 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.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
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.
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- 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.
CPT codes are provided by the performing laboratory.
83090
83918
82136
82542 (if appropriate for government payers)
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 |
|---|---|---|
| CMMPP | CMMP, P | 104535-0 |
| 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.
|
|---|---|---|
| 606110 | Interpretation | 59462-2 |
| 606104 | Total Homocysteine | 13965-9 |
| 606105 | Methylmalonic acid | 13964-2 |
| 606119 | 2-Methylcitric acid | 26904-3 |
| 606106 | Methionine | 20651-6 |
| 606107 | Total Cysteine | 20641-7 |
| 606108 | Cystathionine | 26607-2 |
| 606109 | Reviewed By | 18771-6 |