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What is If urine sample darkens on standing, the most likely condition is : and explain in detail?
Alkaptonuria a condition d/t defective homogentisate 1, 2- dioxygenase (1/t defective tyrosine degradation) usually presents after age of 40 with characteristic triad of Homogentisic aciduria (which blacken/darkens on exposure to air /standing and is strongly Benedict's positive), Ochronosis (i.e black pigmentation of cailage & collagenous connective tissue), and Ahritis of large joints