galactosialidosis

ga·lac·to·si·al·i·do·sis (gə-lak″to-si-al″ĭ-doґsis) an autosomal recessive lysosomal storage disease caused by mutations in the CTSA gene (locus: 20q13.1), which encodes cathepsin A, resulting in deficiency of both neuraminidase (sialidase) and β-galactosidase. It is clinically almost indistinguishable from sialidosis type II. Three phenotypic variants occur, of increasing severity with decreasing age of onset: early infantile, characterized by fetal hydrops, ascites, visceromegaly, and early death; late infantile, characterized by cardiac involvement, hepatosplenomegaly, and growth retardation; and juvenile, characterized by progressive neurological deterioration without visceromegaly.