Test Code LASF1 Lactic Acid, Spinal Fluid
Specimen Required
Specimen Type: Spinal fluid
Container/Tube: Sterile container
Specimen Volume: 1 mL
Collection Instructions: Centrifuge to remove any cellular material.
Secondary ID
601821Useful For
Aid in differentiating between bacterial and viral meningitis
Aid in identifying increased anaerobic glycolysis or hypoxia associated with bacterial meningitis, cerebral infarction, cerebral arteriosclerosis, intracranial hemorrhage, hydrocephalus, traumatic brain injury, cerebral edema, epilepsy, and inborn errors of metabolism
Method Name
Colorimetric
Reporting Name
Lactic Acid, CSFSpecimen Type
CSFSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
CSF | Frozen (preferred) | 60 days | |
Refrigerated | 24 hours | ||
Ambient | 3 hours |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Clinical Information
Anaerobic glycolysis markedly increases lactate concentrations. Lactate concentrations in cerebrospinal fluid (CSF) are increased in the presence of cerebral glycolysis or hypoxia associated with bacterial meningitis, cerebral infarction, cerebral arteriosclerosis, intracranial hemorrhage, hydrocephalus, traumatic brain injury, cerebral edema, epilepsy, and inborn errors of metabolism. Lactate found in CSF is predominantly produced by central nervous system anaerobic glycolysis and is independent of blood lactate. Lactate measurement in CSF has been proposed as a test to differentiate bacterial from viral meningitis.
Reference Values
0-2 days: 1.1-6.7 mmol/L
3-10 days: 1.1-4.4 mmol/L
11 days-17 years: 1.1-2.8 mmol/L
>17 years: 1.1-2.4 mmol/L
Interpretation
In addition to reference intervals, published meta-analysis of 33 studies concluded concentrations greater than 3.9 mmol/L are suggestive of bacterial meningitis, with lower concentrations suggestive of viral meningitis.(1)
Method Description
Lactate concentration is determined using an enzymatic colorimetric method. L-lactate is oxidized to pyruvate by the specific enzyme lactate oxidase. Peroxidase is used to generate a colored dye using the hydrogen peroxide generated in the first reaction. The intensity of the color formed is directly proportional to the L-lactate concentration. It is determined by measuring the increase in absorbance.(Package insert: Roche Diagnostics Cobas 6000; LACT2 reagent package insert; Indianapolis, IN 46256. 02/2016)
Day(s) Performed
Monday through Sunday
Performing Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83605
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
LASF1 | Lactic Acid, CSF | 2520-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
LASF1 | Lactic Acid, CSF | 2520-5 |