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This syndrome is rare with less than 30 cases reported in the literature.

The principle manifestation is progressive calcification of the aorta, and of the aortic and/or mitral valves. Other common features include mild splenomegaly, corneal opacities, and supranuclear ophthalmoplegia.

The disease is caused by homozygous D409H (1342G to C) mutations in the GBA gene (1q21) that encodes the lysosomal membrane-associated glycoprotein, glucosylceramidase. The enzyme deficiency resulting from the mutation leads to accumulation of glucosylceramide (GL1) and other glycolipids in the cells of the reticuloendothelial system.

The diagnosis can be made by measuring glucosylceramidaseactivity and is confirmed by identification of the D409H GBA gene mutation.

Prenatal diagnosis is possible through detection of the glucosylceramidase deficiency in amniocytes or chorionic villus samples, or through screening for the GBA gene mutation in families in which the D409H allele has been identified in both parents or an affected brother or sister.

The syndrome is transmitted in an autosomal recessive manner.

Patients with this syndrome require close monitoring by echocardiography as the cardiac complications require aortic and mitral valve replacement. Enzyme substitution therapy, involving regular intravenous infusions of the recombinant glucosylceramidase enzyme, imiglucerase, has been used successfully in the treatment of this disorder following surgery.

The prognosis for patients depends on the outcome of the heart surgery.