Lysosomal storage diseases are a group of approximately 50 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomal storage diseases result when the lysosome – a specific organelle in the body's cells – malfunctions.
Fabry Disease – an X-linked lysosomal storage disease. It is caused by a deficiency of the lysosomal enzyme alpha-galactosidase A. Patients with Fabry disease are at higher risk of stroke, small-fiber neuropathy, heart disease and kidney disease. Treatment may be disease-specific (enzyme replacement) or non-disease specific yet quite efficacious.
Gaucher Disease – an autosomal recessive lysosomal storage disease caused by a deficiency of the lysosomal enzyme glucocerebrosidase. Patients may have anemia, thrombocytopenia, large spleen and liver and bone disease. Some patients also have neurological involvement. Enzyme replacement therapy or substrate synthesis reduction therapy is highly efficacious therapeutic interventions.
Mucolipidosis Type IV – rare neurodevelopmental brain disease that is associated with progressive retinal degeneration. Patients may be diagnosed by the finding of elevated blood gastrin (a hormone) levels.
Mucopolysaccharidoses – this is a group of lysosomal enzyme deficiencies that cause a variety bone abnormalities and often neurological deficits.
Hurler Disease (Mucopolysaccharidosis Type I)
Hurler Disease (Mucopolysaccharidosis Type II)
Krabbe Disease (Globoid Cell Leukodystrophy) – is caused by galactocerebrosidase deficiency. The infantile form is the most common and the most severe but it can present at any age including in adults.
Metachromatic Leukodystrophy – caused by arylsulfatase A. The most common is the late infantile type with onset at age 15-24 months. The juvenile form has its onset between 3 and 10 years of age. Adult forms exist that often present with psychiatric symptoms.
Niemann-Pick Disease Type A or B – the disease is caused by sphingomyelinase deficiency. Type A has both visceral and brain disease while type B has only visceral involvement. The latter consists of a large liver and spleen and respiratory problems.
Niemann-Pick Type C – this is one of the most common lysosomal storage diseases. It causes progressive brain degeneration is less often liver dysfunction.