A rare manifestation of right ventricular dysfunction in an adult patient with mucolipidosis type III α/β.

Abstract Mucolipidosis type III (ML III) α/β is an autosomal recessive lysosomal storage disease, caused by the deficient activity of UDP-N-acetyl glucosamine-1-phosphotransferase (GlcNAc-PTase). The resultant intra-lysosomal accumulation of partly degraded mucopolysaccharides and sphingolipids causes multiple organ damages including the heart. The most documented cardiac manifestation is the thickening and insufficiency of mitral and aortic valves, but there are very few reports about the myocardial involvement. We report a case with ML III α/β complicated by marked dilatation and dysfunction of the right ventricle (RV), which is quite rare and further broadens the clinical spectrum of the disease.