Pseudo-Hurler polydystrophy

**Pseudo-Hurler polydystrophy**
*Classification & external resources*
ICD-10	E77.0
ICD-9	272.7
OMIM	252600
DiseasesDB	29378
MeSH	D009081

Pseudo-Hurler polydystrophy, also referred to as mucolipidosis III (ML III), is lysosomal storage disease closely related to I-cell disease (ML II). Symptoms of ML III are often not noticed until the child is 3-5 years of age.

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Pathophysiology

As in ML II, ML III results from genetic defects in GlcNAc phosphotransferase (N-acetylglucosamine-1-phosphotransferase). However, ML III produces less severe symptoms and progresses more slowly, probably because the defect in GlcNAc phosphotranspherase lies in its protein recognition domain.^[1] Therefore, the catalytic domain retains some of its activity, resulting in a smaller accumulation of carbohydrates, lipids, and proteins in the inclusion bodies.

Presentation

Patients with ML III are generally of normal intelligence (trait) or have only mild mental retardation. These patients usually have skeletal abnormalities, coarse facial features, short height, and corneal clouding. Some individuals with ML III survive until their fourth or fifth decade of life.

References

^ Murray, R, Granner, D, and Rodwell, V. (2006). Harper's Illustrated Biochemistry. 27^th ed. New York: Lange Medical Books/McGraw-Hill.

mucolipidoses at NINDS - original text of article derived from detail sheet available here

v • d • e Metabolic pathology / Inborn error of metabolism (E70-90, 270-279)
Amino acid	Aromatic (Phenylketonuria, Alkaptonuria, Ochronosis, Tyrosinemia, Albinism, Histidinemia) - Organic acidemias (Maple syrup urine disease, Propionic acidemia, Methylmalonic acidemia, Isovaleric acidemia, 3-Methylcrotonyl-CoA carboxylase deficiency) - Transport (Cystinuria, Cystinosis, Hartnup disease, Fanconi syndrome, Oculocerebrorenal syndrome) - Sulfur (Homocystinuria, Cystathioninuria) - Urea cycle disorder (N-Acetylglutamate synthase deficiency, Carbamoyl phosphate synthetase I deficiency, Ornithine transcarbamylase deficiency, Citrullinemia, Argininosuccinic aciduria, Hyperammonemia) - Glutaric acidemia type 1 - Hyperprolinemia - Sarcosinemia
Carbohydrate	Lactose intolerance - Glycogen storage disease (type I, type II, type III, type IV, type V, type VI, type VII) - fructose metabolism (Fructose intolerance, Fructose bisphosphatase deficiency, Essential fructosuria) - galactose metabolism (Galactosemia, Galactose-1-phosphate uridylyltransferase galactosemia, Galactokinase deficiency) - other intestinal carbohydrate absorption (Glucose-galactose malabsorption, Sucrose intolerance) - pyruvate metabolism and gluconeogenesis (PCD, PDHA) - Pentosuria - Renal glycosuria
Lipid storage	Sphingolipidoses/Gangliosidoses: GM2 gangliosidoses (Sandhoff disease, Tay-Sachs disease) - GM1 gangliosidoses - Mucolipidosis type IV - Gaucher's disease - Niemann-Pick disease - Farber disease - Fabry's disease - Metachromatic leukodystrophy - Krabbe disease Neuronal ceroid lipofuscinosis (Batten disease) - Cerebrotendineous xanthomatosis - Cholesteryl ester storage disease (Wolman disease)
Fatty acid metabolism	Lipoprotein/lipidemias: Hyperlipidemia - Hypercholesterolemia - Familial hypercholesterolemia - Xanthoma - Combined hyperlipidemia - Lecithin cholesterol acyltransferase deficiency - Tangier disease - Abetalipoproteinemia Fatty acid: Adrenoleukodystrophy - Acyl-coA dehydrogenase (Short-chain, Medium-chain, Long-chain 3-hydroxy, Very long-chain) - Carnitine (Primary, I, II)
Mineral	Cu Wilson's disease/Menkes disease - Fe Haemochromatosis - Zn Acrodermatitis enteropathica - PO₄^3�' Hypophosphatemia/Hypophosphatasia - Mg²⁺ Hypermagnesemia/Hypomagnesemia - Ca²⁺ Hypercalcaemia/Hypocalcaemia/Disorders of calcium metabolism
Fluid, electrolyte and acid-base balance	Electrolyte disturbance - Na⁺ Hypernatremia/Hyponatremia - Acidosis (Metabolic, Respiratory, Lactic) - Alkalosis (Metabolic, Respiratory) - Mixed disorder of acid-base balance - H₂O Dehydration/Hypervolemia - K⁺ Hypokalemia/Hyperkalemia - Cl^�' Hyperchloremia/Hypochloremia
Purine and pyrimidine	Hyperuricemia - Lesch-Nyhan syndrome - Xanthinuria
Porphyrin	Acute intermittent, Gunther's, Cutanea tarda, Erythropoietic, Hepatoerythropoietic, Hereditary copro-, Variegate
Bilirubin	Unconjugated (Lucey-Driscoll syndrome, Gilbert's syndrome, Crigler-Najjar syndrome) - Conjugated (Dubin-Johnson syndrome, Rotor syndrome)
Glycosaminoglycan	Mucopolysaccharidosis - 1:Hurler/Hunter - 3:Sanfilippo - 4:Morquio - 6:Maroteaux-Lamy - 7:Sly
Glycoprotein	Mucolipidosis - I-cell disease - Pseudo-Hurler polydystrophy - Aspartylglucosaminuria - Fucosidosis - Alpha-mannosidosis - Sialidosis
Other	Alpha 1-antitrypsin deficiency - Cystic fibrosis - Amyloidosis (Familial Mediterranean fever) - Acatalasia