Wednesday, 6 August 2014

Copper

Why is copper  required in body ?

What if there is deficiency of copper ?

what if there is excess of copper ?

1. Copper acts as cofacter for various enzymes = TYROSINASE , LYSYL OXIDASE , SUPEROXIDE DISMUTASE, CYTOCHROME C OXIDASE, DOPAMINE BETA HYDROXYLASE. [Q]

2. If there is deficiency of copper these enzymes will not work properly as for eg in copper deficient state lysyl oxidase will not work and there will be ineffectual cross linking in collagen and elastin leading to weakened vascular wall and fragile skin.



MENKES DISEASE IS A X-LINKED RECESSIVE DISORDER DUE TO DEFICIENCY OF COPPER

PATHOGENESIS : Defect in ATP7A gene[Q] so that copper is absorbed in the intestinal eptithelial cells but cant be transported out of intestinal epithelial cells into blood stream so that the intestinal epithelial cells are loaded with copper but there is deficiency of copper in body.

CLINICS : Mental retardation , seizures , hypothermia , twisted and hypopigmented hair (pili torti) , loose skin , arterial rupture and death in early childhood.

TREATMENT : To give copper by any other route than oral becoz intestinal absorption is impaired. Subcutaneous route copper is given and show some clinical improvement in disease state.



WILSON DISEASE IS DUE TO EXCESS DEPOSITION OF COPPER IN VARIOUS PARTS OF BODY:

PATHOGENESIS : Defect in ATP7B gene( CHROMOSOME 13)[Q] leads to defective excretion of copper from hepatocytes into billiary tree leading to copper excess in body . Two most commonly effected organ is liver and brain so also known as HEPATOLENTICULAR DEGENERATION.

CLINICS : It usually presents with acute or chronic liver disease in childhood . Liver disease is progressive if left untreated. Adults develop neurological symptoms as dysarthria and diminished cordination. Copper accumulation can also lead to arthropathy , cardiomyopathy, kidney damage and hypoparathyroidism , decemets membrane formation.

TREATMENT : Chelating agents as penicillamine and ammonium tetrathiomolybdate.



so to compile

MENKES = COPPER DEFICIENCY = ATP7A GENE = X-LINKED RECESSIVE = DEFECTIVE COPPER ABSORPTION

WILSON = COPER EXCESS = ATP7B GENE = CHROMOSOME 13 = AUTOSOMAL RECESIVE = DEFECTIVE COPPER EXCRETION

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