A hereditary autosomal recessive lysosomal storage disease associated with a combined deficiency of beta-galactosidase and neuraminidase, secondary to a defect in protective protein/cathepsin A (PPCA). All patients have clinical manifestations typical of a lysosomal disorder, such as coarse FACIES, cherry red spots, vertebral changes, foam cells in the bone marrow, and vacuolated LYMPHOCYTES. Three phenotypic subtypes are recognized. The early infantile form is associated with HYDROPS FETALIS; EDEMA; ASCITES, visceromegaly, skeletal dysplasia, and early death. The late infantile type is characterized by hepatosplenomegaly, growth retardation, cardiac involvement, and rare occurrence of neurologic signs. The juvenile/adult form is characterized by MYOCLONUS; ATAXIA; ANGIOKERATOMA; INTELLECTUAL DISABILITY, neurologic deterioration, absence of visceromegaly, and long survival. The majority of reported patients belong to the juvenile/adult group and are mainly of Japanese origin. Mutations in the CTSA gene have been identified. OMIM: 256540
Date introduced: August 25, 2010