Lysosomal storage disorders

Lysosomes are cell organelles whose function is to break down complex macromolecules into small fragments. The degradation is accomplished by a great number of hydrolases, with each being individually specialised for digestion of a specific substrate. A genetic defect of one single enzyme leads to accumulation of substances that cannot be degraded, resulting in disturbed function of several organ systems. Common to all lysosomal storage disorders is the progressive course of the disease. After initially normal development, characteristic signs and symptoms arise, including hepatosplenomegaly, skeletal deformities, and mental retardation. Until recently, management consisted solely of supportive care and treatment of complications. But now, preparations for enzyme replacement therapy are available for some lysosomal storage disorders. Substrate reduction therapy represents another therapeutic option.