ALKAPTONURIA-- A CASE REPORT OF RARE DISEASE

Abstract

Alkaptonuria also known as Black Bone Disease  or  Black urine disease is a rare autosomal recessive disorder. It was first described by Archibald Garrod as an inborn error of metabolism in 1902 in London.(4 ).The problem is in tyrosine metabolism  in the liver due to deficiency of homogentisinate 1,2 dioxygenase (HGD).Which results in accumulation of  homogentisic acid (HGA) in the cells and body fluids. The oxidized polymers bind to collagen, leading to progressive deposition of grey to bluish black pigment resulting in degenerative changes in  cartilage, intervertebral disc and other connective tissues leading to arthritis This is the main disabling  effect seen in later life. The diagnosis can be made in neonates and infancy  when blackish stain is noticed in an unchanged diaper. The classical triad is that of that of homogentisic aciduria, arthritis and ochronosis. Treatment of Alkaptonuria is mainly symptomatic. Ascorbic acid (Vit C) and dietary restriction of foods containing phenylalanine and tyrosine is recommended. Surgical intervention may be required at a later date in advanced stages. The disease is very common in  Dominion Republic and Slovakia.