Family history of ochronotic arthropathy.

Alkaptonuria is a rare autosomal-recessive disorder that produces accumulation of homogentisic acid in body fluids. The accumulation in collagen tissues, mainly in the joint cartilage, produces ochronotic arthropathy. We report two clinical cases of one brother and sister with alkaptonuria and ochronotic arthropathy diagnosed in old age. In the first case, the patient is diagnosed by musculoskeletal involvement with long-term low back pain with other associated manifestations that made this pathology suspected. In the second case, the patient comes due to osteoporosis and other associated fractures and with the family history and the rest of the clinic, the appropriate complementary tests were performed and the diagnosis is established. It is unknown if there is consanguinity in these patients between parents or ancestors. It is an infrequent pathology that is often diagnosed intraoperatively. Despite the poor efficacy of medical treatment, it would be advisable to make an early diagnosis to avoid accumulation of the pigment and accelerated joint destruction and deposition in other locations. Owing to its prevalence, it is difficult to find a significant number of patients to search for new treatments that are intended to correct the enzyme deficit and not only to modify the elimination.