Introduce the ochronosis, an uncommon disorder of metabolism. Overview the physiopathology process of this rare condition. To present the clinical aspects and the radiological manifestations of ochronosis.

Ochronosis is one of three clinical types in the spectrum of alterations originated by Alcaptonuria (AKU), an inborn error of metabolism. This spectrum is a continuum of modifications based on the deficiency of the enzyme homogentisate 1,2 dioxygenase (HGD), which is responsible for the cleansing of homogentisic acid (HGA), an intermediate metabolite of phenylalanine and tyrosine amino acids metabolism in the liver. HGA, which is a brownish pigment, accumulates in the intracellular and extracellular environment of the connective tissues and is excreted by the kidneys,...

Early diagnosis of Ochronosis is difficult because it is a rare disease, few know about it and even who knows hardly consider this diagnose. Patients in the age group of 30 to 50 years usually look for medical attention not because of the skin or eye blemishes. They go to medical service because of low back pain with no previous history of trauma, being diagnosed with postural or labor low back pain receiving symptomatic treatment. Radiological signs of Ochronosis, if present at this time, are...

Although rare, Ochronosis has been increasingly divulged, given the growing number of scientific articles and case reports of this disease published in the scientific community. This evidences that, despite being a difficult diagnosis, many patients were identified even with an advanced clinical condition and irreversible alterations, but still in time to prevent a worse disease progression with more life quality impairment. In this sense, the radiologist must recognize this disease to diagnose it correctly, helping the scientific community to better understand this condition and so...

F. A. Oliveira; Ribeirão Preto/BR - nothing to disclose M. H. H. Nogueira-Barbosa; Ribeirão Preto/BR - nothing to disclose O. T. Moritsugu; Ribeirão Preto/BR - nothing to disclose

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