Back to Test Compendium

Pyruvate, CSF (Referred Out) - Saskatoon

Discipline

Biochemistry

Overview

Description

Ordering Recommendation

  • CSF Lactate shall be ordered in conjunction with CSF Pyruvate collections.  Specimens shall be collected at the same time. Pyruvic acid levels alone have little clinical utility.

​Test Ordering Requirements

Preferred Specimen Collection
  • RUH
​Forms Required

Specimen Information

Specimen types accepted

  • ​Cerebrospinal Fluid

Specimen collection container

  • ​Preferred Collection Container: Sterile screw top tubes supplied in Spinal tap kit
  • Send specimen from vial 4

Required volume

  • ​Optimal Volume: 0.6 mL
  • Minimum Volume: 0.5 mL

(Submitting the minimum volume makes it impossible to repeat the test or perform confirmatory/reflex testing. In some situations, a minimum volume may require a second collection.)

Transport and stability

  • Stable for 7 days
  • Ship on dry ice to referral laboratory

Rejection criteria

Testing Information

Relevant clinical history

  • Family history
  • Must include diagnosis and/or patient symptoms on the requisition

Clinical interpretation

  • Abnormal concentrations of pyruvic acid, and lactate-to-pyruvate (L:P) ratios, are not diagnostic for a particular disorder but must be interpreted in the context of the patient's clinical presentation and other laboratory studies. The determination of pyruvic acid is of diagnostic value when lactic acid is measured and the L:P ratio is established in the same specimen.
  • 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. When comparing blood and CSF L:P ratios, blood and CSF specimens should be collected at the same time.

Performance

Methodology

  • Enzyme/UV Detection

Days/times performed

Availability
  • Monday to Thursday, 8:00 a.m. - 2:00 p.m.
Testing Site
  • Referred out by St. Paul’s Hospital Laboratory to Mayo Medical Laboratories

Maximum laboratory time

Results Reporting
  • 10-14 day turnaround time by referral laboratory

Last Updated: October 8, 2024