Sign in →

Test Code LAB7540 Pyruvate, Spinal Fluid

Additional Codes

PYRC

Useful For

Investigating possible disorders of mitochondrial metabolism, when used in conjunction with cerebrospinal fluid lactate, collected at the same time, to determine the lactate-to-pyruvate (L:P) ratio

 

Evaluating patients with neurologic dysfunction and normal blood L:P ratios

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

CSF


Additional Testing Requirements


This test does not calculate the lactate:pyruvate ratio. To obtain this information, both this test and LASF1 / Lactic Acid, Spinal Fluid must be ordered. The ratio can be calculated from the results obtained from these tests.



Specimen Required


Specimen Type: Spinal fluid

Container/Tube: Sterile vial

Specimen Volume: 0.6 mL

Collection Instructions: Send specimen from vial 4.


Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
CSF Refrigerated (preferred) 7 days
  Frozen  14 days
  Ambient  7 days

Reference Values

0.06-0.19 mmol/L

Day(s) Performed

Monday, Wednesday

CPT Code Information

84210

LOINC Code Information

Test ID Test Order Name Order LOINC Value
PYRC Pyruvic Acid, CSF 14122-6

 

Result ID Test Result Name Result LOINC Value
83356 Pyruvic Acid, CSF 14122-6

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 in acutely ill patients.

Method Description

Pyruvate, in the presence of excess nicotinamide adenine dinucleotide, hydrogen ions, and lactic dehydrogenase, is reduced to lactate. The reaction is stoichiometric; the decrease in absorbance at 340 nm is directly proportional to the concentration of pyruvate.(Huckabee WE. Relationships of pyruvate and lactate during anaerobic metabolism. I. Effects of infusion of pyruvate or glucose and of hyperventilation. J Clin Invest. 1958;37(2):244-254; Benoist JF, Alberti C, Leclercq S, et al. Cerebrospinal fluid lactate and pyruvate concentrations and their ratio in children: age-related reference intervals. Clin Chem. 2003;49[3]:487-494; Cowan T, Pasquali M. Laboratory investigations of inborn errors of metabolism. In: Sarafoglou K, Hoffman GF, Roth KS, eds. Pediatric Endocrinology and Inborn Errors of Metabolism. 2nd ed. McGraw-Hill; 2017:1139-1158)

Report Available

4 to 8 days

Specimen Retention Time

2 months

Reject Due To

Gross hemolysis Reject

Method Name

Spectrophotometry (SP)

Testing Algorithm

For more information see: Epilepsy: Unexplained Refractory and/or Familial Testing Algorithm