Test Id : LAPYP
Lactate Pyruvate Panel, Plasma
    
        Useful For
            
                
                
                    
                    Suggests clinical disorders or settings where the test may be helpful
                
            
    
    Diagnosing and monitoring patients with lactic acidosis
Monitoring lactate-to-pyruvate ratios
    
        Highlights
    
    This test provides results for both lactate and pyruvate on a single collection
    
        Testing Algorithm
            
                
                
                    
                    Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
                
            
    
    For more information see Epilepsy: Unexplained Refractory and/or Familial Testing Algorithm
    
        Method Name
            
                
                
                    
                    A short description of the method used to perform the test
                
            
    
    Gas Chromatography Mass Spectrometry (GC-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
                
            
    
    Lactate
Lactic acid
Pyruvate
Pyruvic acid
    
        Testing Algorithm
            
                
                
                    
                    Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
                
            
    
    For more information see Epilepsy: Unexplained Refractory and/or Familial Testing Algorithm
    
        Specimen Type
            
                
                
                    
                    Describes the specimen type validated for testing
                
            
    
        Plasma
    
        Ordering Guidance
    
    This test does not measure D-lactate, an uncommon, often undiagnosed cause of lactic acidosis. If D-lactate testing is needed, order DLAU / D-Lactate, Urine (preferred) or DLAC / D-Lactate, Plasma.
Analytes from this test are included in test MMPP / Mitochondrial Metabolites, Plasma. If ordered together, this test may be canceled.
    
        Specimen Required
            
                
                
                    
                    Defines the optimal specimen required to perform the test and the preferred volume to complete testing
                
            
    
    Collection Container/Tube:
Preferred: Green top (Sodium heparin)
Acceptable: Green top (Lithium heparin)
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot plasma into a plastic vial.
    
        Special Instructions
            
                
                
                    
                    Library of PDFs including pertinent information and forms related to the test
                
            
    
    
            
    
        Forms
    
    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.
                
            
    
    0.1 mL
    
        Reject Due To
            
                
                
                    
                    Identifies specimen types and conditions that may cause the specimen to be rejected
                
            
    
    | Gross hemolysis | Reject | 
| 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 | Frozen (preferred) | 90 days | |
| Ambient | 7 days | ||
| Refrigerated | 7 days | 
    
        Useful For
            
                
                
                    
                    Suggests clinical disorders or settings where the test may be helpful
                
            
    
    Diagnosing and monitoring patients with lactic acidosis
Monitoring lactate-to-pyruvate ratios
    
        Testing Algorithm
            
                
                
                    
                    Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
                
            
    
    For more information see Epilepsy: Unexplained Refractory and/or Familial Testing Algorithm
    
        Clinical Information
            
                
                
                    
                    Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
                
            
    
    Lactic acid (lactate) is primarily produced from glucose metabolism via the glycolytic pathway. Although primarily metabolized by the liver, other tissues also use small amounts of lactate. Typically, the amount of lactate produced parallels the amount utilized. Both the rates of lactate production and liver clearance impact the lactate concentration in blood. Lactic acidosis, or the accumulation of excess lactate, results from a combination of increased lactate production with decreased utilization.
Patients experiencing lactic acidosis present with tachypnea, weakness, and fatigue. Untreated, patients may develop confusion and progress to coma. Lactic acidosis may be associated with hypoxic conditions (eg, shock, hypovolemia, heart failure, pulmonary insufficiency), metabolic disorders (eg, diabetic ketoacidosis, malignancies, inborn errors of metabolism), and toxin exposures (eg, ethanol, methanol, salicylates).
Pyruvic acid, an intermediate metabolite, plays an important role in linking carbohydrate and amino acid metabolism to the tricarboxylic acid cycle, the fatty acid beta-oxidation pathway, and the mitochondrial respiratory chain complex. However, pyruvic acid levels alone have little clinical utility.
Combined analysis of lactate and pyruvate may suggest an inborn error of metabolism when elevations of both analytes are observed or when there is an abnormal lactate-to-pyruvate (L:P) ratio. For example, several mitochondrial respiratory chain disorders exhibit elevated L:P ratios. Mitochondrial disorders vary widely in both clinical presentation and age of onset. Patients commonly present with neurologic and myopathic features. In addition, patients may experience involvement of multiple organ systems with features such as myopathy, ophthalmoplegia, ptosis, cardiomyopathy, sensorineural hearing loss, optic atrophy, pigmentary retinopathy, diabetes mellitus, encephalomyopathy, seizures, and stroke-like episodes.
A low L:P ratio is observed in inherited disorders of pyruvate metabolism including pyruvate dehydrogenase complex (PDHC) deficiency. Clinical presentation of PDHC deficiency can range from fatal congenital lactic acidosis to relatively mild ataxia or neuropathy. The most common features observed in infants and children with PDHC deficiency are developmental delay, hypotonia, seizures, and ataxia. Other manifestations may include congenital brain malformations, degenerative changes including Leigh disease, and facial dysmorphism.
    
        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.
                
            
    
    Lactic Acid
< or = 4000.0 nmol/mL
Pyruvic Acid
< or = 350.0 nmol/mL
    
        Interpretation
            
                
                
                    
                    Provides information to assist in interpretation of the test results
                
            
    
    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.
    
        Cautions
            
                
                
                    
                    Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
                
            
    
    No significant cautionary statements
    
        Clinical Reference
            
                
                
                    
                    Recommendations for in-depth reading of a clinical nature
                
            
    
    1. Munnich A, Rotig A, Cormier-Daire V, Rustin P. Clinical presentation of respiratory chain deficiency. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed July 5, 2024. Available at http://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225086827
2. Robinson BH. Lactic acidemia: Disorders of pyruvate carboxylase and pyruvate dehydrogenase. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed July 5, 2024. Available at http://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225087140
3. Shoffner JM. Oxidative phosphorylation diseases. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, eds. Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019 Accessed July 5, 2024. Available at http://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225088339
    
        Method Description
            
                
                
                    
                    Describes how the test is performed and provides a method-specific reference
                
            
    
    A mixture of labeled internal standards is added to patient plasma following oximation of keto acids. The samples are acidified and extracted. After evaporation, the dry residue is silylated analyzed by capillary gas chromatography mass spectrometry using selected ion monitoring with positive electron impact ionization and stable isotope dilution.(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.
                
            
    
    Wednesday
    
        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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        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.
83605
84210
    
        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 | 
|---|---|---|
| LAPYP | Lactate Pyruvate Panel, P | 101656-7 | 
| 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.
                                     | 
|---|---|---|
| 616797 | Interpretation | 59462-2 | 
| 616794 | Lactic acid | 2524-7 | 
| 616795 | Pyruvic acid | 32338-6 | 
| 616796 | Reviewed by | 18771-6 |