Radiological - Pathological Correlation in a Late Diagnosis of Oochronosis

Introduction: Alkaptonuria is a rare autosomal recessive multisystem disorder of phenylalanine/tyrosine metabolism which occurs due to lack of homogentisic acid oxidase, which causes homogentisic acid deposition in the tissues. Alkaptonuria is characterized by a triad of homogentisic aciduria, oochronosis, and precious degenerative arthropathy. Oochronosis is blue -blackish discoloration of skin and cartilage involving multiple sites like ear pinna, cheeks, palms, soles, etc as well as urine that turns black upon standing. Case Report: This is a case report of oochronosis secondary to alkaptonuria. A female patient in her 60's presented with chief complaints of acute severe chest pain radiating to left arm from 1 day and, chronic back pain, and bilateral hip joint pain for the last 6 years. On physical examination, the Patient had bluish -blackish subcutaneous discoloration involving multiple sites like bilateral palms, soles, and cheeks. Patches of bluish -blackish ocular pigmentation were also noted in bilateral sclera. The patient also had lumbar spinal stiffness and a restricted range of motion of the knee joint. Extensive disc calcification involving the whole spine, vacuum discal phenomenon, and osteophytic bridges were demonstrated on standard radiograph and computer tomography scans. Clinical, radiograph and histopathological criteria were used to make the diagnosis of ochronosis. Conclusion: Alkaptonuria is a autosomal recessive multisystem disorder that causes degenerative arthropathy that leads to reduction of functional ability. The use of molecular analysis and genetic research is very useful.