cystinosis

cystinosis /cys·ti·no·sis/ (-o´sis) a hereditary disorder of cystine metabolism; the most common type appears in childhood with osteomalacia, aminoaciduria, phosphaturia, and deposition of cystine in tissues throughout the body, leading to renal failure.

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cys·ti·no·sis (sst-nss)

n.

A hereditary dysfunction of the renal tubules characterized by the presence of carbohydrates and amino acids in the urine, excessive urination, and low blood levels of potassium ions and phosphates, and caused by the abnormal metabolism of cystine and the accumulation of cystine crystals in tissues; it occurs in young children. Also called cystine storage disease.

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cystinosis Molecular medicine Any of 3–types I, II, III–AR conditios characterized by impaired transport of cystine across lysosomal membranes; the accumulation of cystine in lysosomes results in crystal formation in various tissues, in particular the kidneys; early renal tubular involvement results in Fanconi syndrome with FTT, dehydration, renal tube acidosis in infancy; cystal-related loss of glomerular function leads to uremia and death by age 10 Clinical Growth retardation, photophobia, hypothyroidism, and in later survivors, visual impairment, corneal ulcerations, pancreatic insufficiency, distal myopathy, dysphagia, CNS involvement Management Cysteamine- β-mercaptoethylamine, or phosphocysteamine removes cystine crystals. See Nephropathic cystinosis.