Mucopolysaccharidosis type 1H (MPS1H), also known as Hurler syndrome, Hurler's disease or gargoylism, is the most severe form of mucopolysaccharidosis type 1.
MPS1H presents as a multisystem disorder in the early childhood . Most important manifestation is developmental delay which becomes evident by the end of first year of life. There is also progressive mental deterioration. The systemic manifestations are classified as:
MPS1H is a genetic disease which can be diagnosed either in the prenatal period or after the birth of the baby. A number of laboratory, as well as radiological investigations, are helpful to determine the diagnosis of the disease.
Treatment of MPS1H involves palliative and curative elements . Enzyme replacement therapy with L-iduronidase is helpful in improving pulmonary function  . The walking ability of the person is also improved. In addition, it reduces the carbohydrate storage in organs .
In patients with hand, foot and joint deformities, surgical treatment is quite helpful in correcting the abnormality . Corneal clouding can be treated by corneal transplant. Some studies have shown decreased corneal opacity and improved vision even with enzyme replacement therapy .
There are no specific etiological or causative factors for MPS1H. It is classified as one of the lysosomal storage disorders and is genetic in origin. The disease is transferred as an autosomal recessive trait which means that the affected person should have two defective copies of the IDUA gene. This gene is responsible for the synthesis of the enzyme alpha-L-iduronidase . If both the parents have a single mutated copy of the gene (i.e. both parents are unaffected carriers) there is a 25% chance in each of their children to have MPS1H.
MPS1H is an autosomal recessive disorder which affects both sexes equally. The annual incidence of this syndrome in the United States is 1 case per 100, 000 cases. The prevalence of the disease in the UK was estimated to be about 1.07 cases per 100, 000 births from the years 1981 to 2003 .
MPS1H is a metabolic disorder in which there is abnormal accumulation of metabolites of glycosaminoglycans in different cells of the body either due to the absence or a deficiency of a specific lysosomal enzyme alpha-L-iduronidase required for the degradation of glycosaminoglycans, dermatin sulfate and heparin sulfate resulting in organ dysfunction. Genetic mutations in the IDUA gene located on chromosome 4 site 4p16.3 result in the absence or a deficiency of the enzyme and lead to the development of Hurler syndrome.
Glycosaminoglycans are essential components of the extracellular matrix, connective tissue, and joint fluid. The degradation of these macromolecules is brought about by the lysosomal enzyme alpha-L-iduronidase. This breakdown process is essential for normal tissue growth and tissue homeostasis. If there is accumulation of these compounds within the cells it causes cell, tissue and organ dysfunction. In addition, there is an increased urinary excretion of heparin sulfate and dermatin sulfate.
MPS1H is a genetic disorder. There is no preventive measure against it.
MPS1H is a genetic metabolic disorder characterized by the deficiency of a lysosomal enzyme alpha-L-iduronidase. This enzyme is responsible for the breakdown of muccopolysaccharides also known as glycosaminoglycans. The deficiency of this enzyme therefore results in the accumulation of muccopolysaccharides in the body. MPS1H is an autosomal recessive disorder that is passed from parents to offsprings. If both the parents carry the defective gene, there is a 25% chance of developing the disease in each of their children. The disease affects many systems of the body. The most common manifestations are physical and mental growth retardation in children usually by the end of first year. Death mostly occurs by the age of 10 years due to organ damage.
MPS1H is a genetic disease which occurs due to the absence or deficiency of an enzyme alpha-L-iduronidase which results in accumulation of certain substances in the body leading to organ dysfunction. The disease runs in families and is transmitted from parents to their offspring. The syndrome manifests as abnormalities in various systems of the body as skeletal and mental abnormalities, joint and bone deformities as well as heart problems. There is no specific treatment of the disease and the affected children usually have a poor prognosis.