Test Catalog

Test ID: LACS1    
Lactate, Plasma

Useful For Suggests clinical disorders or settings where the test may be helpful

Diagnosing and monitoring patients with lactic acidosis

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Anaerobic glycolysis markedly increases blood lactate and causes some increase in pyruvate levels, especially with prolonged exercise. The common cause for increased blood lactate and pyruvate is anoxia resulting from such conditions as shock, pneumonia, and congestive heart failure. Lactic acidosis may also occur in renal failure and leukemia. Thiamine deficiency and diabetic ketoacidosis are associated with increased levels of lactate and pyruvate.


Lactate measurements that evaluate the acid-base status are used in the diagnosis and treatment of lactic acidosis (abnormally high acidity in the blood).

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.

0-90 days (<3 months): < or =3.3 mmol/L

3-24 months: < or =3.1 mmol/L

>24 months-18 years: < or =2.2 mmol/L

>18 years: 0.5-2.2 mmol/L

Interpretation Provides information to assist in interpretation of the test results

While no definitive concentration of lactate has been established for the diagnosis of lactic acidosis, lactate concentrations exceeding 5 mmol/L and pH below 7.25 are generally considered indicative of significant lactic acidosis.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Proper specimen collection and processing techniques are critical for reliable results.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Mizock BA: The hepatosplanchnic area and hyperlactatemia: A tale of two lactates. Crit Care Med 2001;29(2):447-449

2. Duke T: Dysoxia and lactate. Arch Dis Child 1999;81(4):343-350