Specimen Collection Manual and Test Catalog

3 mL whole blood; minimum 0.5 mL

Frozen.

Room temperature: 7 days. Refrigerated: 14 days. Frozen: 28 days.

Quest test code 36455, LAL Activity

Lysosomal acid lipase deficiency (LAL-D) is a lipid storage disorder with two clinically distinct phenotypes, Wolman disease (WD) and cholesteryl ester storage disease (CESD). Both phenotypes follow an autosomal recessive inheritance pattern and are caused by mutation in the LIPA gene. WD, the early onset phenotype of LAL deficiency, is characterized by vomiting, diarrhea, failure to thrive, abdominal distension, and hepatosplenomegaly. Peripheral blood lymphocytes are vacuolated and foam cells are present in the bone marrow. Approximately 50% of infants have adrenal calcifications. WD typically presents in the first weeks of life and is fatal in infancy. CESD, the late onset phenotype of LAL deficiency, is clinically variable with patients presenting at any age with progressive hepatomegaly and often splenomegaly, leading to microvesicular steatosis and often liver failure. CESD is likely underdiagnosed and frequently diagnosed incidentally after liver pathology reveals findings similar to non- alcoholic fatty liver disease (NAFLD) or nonalcoholic steatohepatitis (NASH). The LAL-D test is used to evaluate patients with a clinical presentation suggestive of lysosomal acid lipase deficiency and support a diagnosis of disease.