Ocronosis endógena: un caso de diagnóstico tardío con manifestaciones cutáneas, osteoarticulares y renales.

BACKGROUND: Endogenous ochronosis or alkaptonuria is a rare disease of autosomal recessive inheritance, which manifests with a brown or ocher hue caused by the insufficiency of the homogentisic acid oxidase enzyme causing its accumulation in the connective tissues. CLINICAL CASE: A 56-year-old female patient, with a history of renal lithiasis, presenting with one year evolution of ocher, erythematous and grayish-blue macules on the ears and hands, asymptomatic. The biopsy showed yellowish-brown material in the shape of a banana, with the presence of choluria when performing the urinary alkalinization test with bicarbonate; the imaging studies showed lumbar spondyloarthrosis and annular disc protrusion with foraminal involvement. CONCLUSIONS: Alkaptonuria is a disease with multiple clinical manifestations, it is characteristic the darkening in the urine, the presence of multiple ocher-toned macules and multiple joint conditions; the definitive diagnosis is stablished by measuring the levels of homogentisic acid in urine or with a genetic study; it is recommended to perform biopsies in the macules in search of the characteristic pigment and to carry out an integral approach with paraclinical studies such as magnetic resonance imaging, echocardiography, and ultrasound studies, the treatment is mainly symptomatic. [ABSTRACT FROM AUTHOR]