Test Catalog

Test ID: LALB    
Lysosomal Acid Lipase, Blood

Method Description Describes how the test is performed and provides a method-specific reference

The whole blood specimen is spotted onto filter paper. A 3-mm (one-eighth-inch) disk is punched out of the dried blood spot into a microcentrifuge tube and 200 mcL of water is added as a preincubation extraction that takes place on an orbital shaker for 60 minutes at ambient conditions. Forty (40) mcL of the extraction liquid is combined with either 10 mcL of water (total activity well) or 10 mcL of 30 mcM Lalistat (inhibited well) in a black 96-well plate (50 mcL total volume). The plate is incubated for 10 minutes at 37 degrees C. The substrate consists of 150 mcL of 13.6 mM 4-methylumbelliferyl palmitate in 0.15 M acetate buffer, pH 4.0 plus 1.0% Triton and 0.5% cardiolipin and is added to the same plate (200 mcL total volume). After the incubation period (3 hours at 37 degrees C), calibrators are prepared and analyzed on every plate to calculate enzyme activity results based on fluorescence units in patient wells vs calibrators. The calibration is derived from 4-methylumbelliferone (4-MU) that is serially diluted manually in the plate, with the highest calibrator being equivalent to an enzyme activity of 672.0 nmol/hour/mL blood. The plate is then ready to be read using the spectrofluorometer. Enzyme activity is calculated by subtracting the inhibited activity from total activity.(Hamilton J, Jones I, Srivastava R, Galloway P: A new method for the measurement of lysosomal acid lipase in dried blood spots using the inhibitor Lalistat. Clin Chim Acta 2012;413:1207-1210)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.


Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

8 days

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Clinic Laboratories until the release of the test result

15 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

1 year

Performing Laboratory Location Indicates the location of the laboratory that performs the test