Test Code Billings Clinic: 8613 Mayo: PYR Pyruvic Acid, Blood
Reporting Name
Pyruvic Acid, BPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Screening for possible disorders of mitochondrial metabolism, when used in conjunction with blood lactate collected at the same time, to determine the lactate-to-pyruvate ratio
Method Name
Spectrophotometry (SP)
Additional Testing Requirements
This test does not calculate the lactate:pyruvate ratio. To obtain this information, both this test and LACS1 / Lactate, Plasma must be ordered. The ratio can be calculated from the results obtained from these tests. A separate specimen must be obtained for lactate testing, see LACS1 / Lactate, Plasma.
Specimen Required
Call 800-533-1710 or 507-266-5700 to order special collection tube.
Patient Preparation: Fasting (at least 4 hours)
Supplies: Perchloric Acid-Pyruvate Tube (T012)
Container/Tube: Special collection tube containing 2.5 mL of 6% perchloric acid
Specimen Volume: Exactly 1 mL
Collection Instructions:
1. Special collection tube must be prechilled prior to collection.
2. Draw enough blood directly into syringe to add exactly 1 mL of blood to the prechilled special collection tube.
3. Taking care to not spill any of the preservative, cautiously remove the cap from the tube.
4. Immediately transfer blood, once drawn, to the prechilled, special collection tube, recap, and shake vigorously to mix.
Additional Information:
1. Check expiration date before using. Supplied collection tube expires 14 months after preparation.
2. If perchloric acid (preservative) spills, obtain a new, prechilled tube.
Specimen Type
Whole bloodSpecimen Minimum Volume
See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole blood | Refrigerated | 15 days | PYRUVATE |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Reference Values
0.08-0.16 mmol/L
NIH Unit
0.7-1.4 mg/dL
Interpretation
An elevated lactate-to-pyruvate (L:P) ratio may indicate inherited disorders of the respiratory chain complex, tricarboxylic acid cycle disorders and pyruvate carboxylase deficiency. Respiratory chain defects usually result in L:P ratios above 20.
A low L:P ratio (disproportionately elevated pyruvic acid) may indicate an inherited disorder of pyruvate metabolism. Defects of the pyruvate dehydrogenase complex result in L:P ratios below 10.
The L:P ratio is characteristically normal in other patients. An artifactually high ratio can be found if the patient is acutely ill.
Cerebrospinal fluid (CSF) L:P ratio may assist in evaluation of patients with neurologic dysfunction and normal blood L:P ratios. Blood and CSF specimens should be collected at the same time.
Day(s) Performed
Monday, Wednesday
Report Available
2 to 5 daysTest 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
84210
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PYR | Pyruvic Acid, B | 14121-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
8657 | Pyruvic Acid, B | 14121-8 |
7729 | Pyruvic Acid, B | 2905-8 |
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.
Special Instructions
Testing Algorithm
See Epilepsy: Unexplained Refractory and/or Familial Testing Algorithm