<prompt> Oochronosis occurs in: RepeatAlkaptonuriaIsovaleric aciduriaPhenyl ketonuriaTyrosinemia  <response>: Ans: A Alkaptonuria Ref: Harrisons Principles of Internal Medicine, 18th ed.Explanation:AlkaptonuriaAutosomal RecessiveDue to deficiency of homogentisic acid oxidaseClinical featuresOochronosisArthritisCardiac valve involvementCoronary artery calcification Pigmented heart valves, sclera, joint, skin renal calculiUrine darkens on standingNitisinone used to reduce urinary excretion of homogentisic acid 