Homogentisic Acid, 24 Hour Urine

Phenylalanine and tyrosine, two amino acids, are degraded along the tyrosine degradation pathway to acetoacetic acid and fumaric acid. In alkaptonuria, an inherited disorder of amino acid metabolism, one of the enzymes in tyrosine degradation pathway, homogentisate 1, 2-dioxygenase is absent, leading to the accumulation of homogentisic acid. Homogentisic acid and its metabolites accumulate in collagenous tissues causing ochronosis (bluish-black discolouration), characterised by darkened cartilaginous tissues, arthritis and joint destruction, and deterioration of cardiac valves. Homogentisic acid is excreted in urine, turning dark brown or black upon oxygenation and alkalinisation.

Homogentisic Acid is used in the diagnosis of the inherited metabolic disorder Alkaptonuria (ochronosis). The most common clinical features are discoloration of the urine; pigmentation of the skin, sclerae, and ear cartilage; and ochronotic arthropathy affecting mainly the vertebral discs and large joints. Less common manifestations include renal, urethral, and prostate calculi and cardiovascular abnormalities, especially valvular disease.

10 ml 24 Hrs Urine

Frozen State 24 Hrs urine volume.

< 0.1 g/ 24 Hrs