Exogenous ochronosis is an infrequent dermatosis characterized as a dark blue hyperpigmentation localized where the causing agent was applied. It may be caused by the use of systemic medication such as antimalarials and by the use of topic substances such as phenol, resorcinol, benzene, or hydroquinone, which is a fenolic compound with depigmentation action, largely used in the treatment of mel...

Four cases of operative treatment for ochronosis arthropathy in patients with alcaptonuria are presented. In 3 hip joint and 1 patient knee were affected. Prior to surgery all treated conservatively. Two successfully underwent total replacement. Intertrochanteric femur osteotomy was performed case. the fourth arthroplasty allograft from rib cartilage failed due suppurative arthritis resulted re...

Introduction: Ochronosis is a rare autosomal recessive disorder of tyrosine metabolism, leading to deposition of elevated levels of homogentisic acid in different parts of the body, especially in fibrous and cartilaginous tissues. The current study presents a case with delayed diagnosis and osteoporotic fracture in addition to severe osteoarthritis and calcification. Case Presentation: A 56-yea...

Alcaptonuria is an extremely rare metabolic disease and is defined as an autosomal recessive inherited deficiency of the hepatic enzyme oxidase of the homogentisic acid [1,2] (Figure 1). Deficiency of the enzyme causes accumulation of the homogentisic acid in the cells and the body fluids. The disease is characterized by the following three specific conditions, excretion of homogentisic acid in...

Alkaptonuria is a rare metabolic disease in which a deficiency of the enzyme homogentisate dioxygenase causes an accumulation of homogentisic acid. Ochronosis consists of excessive deposition of homogentisic acid in the connective tissue and presents as a chestnut brown or black pigmentation. With aging, the accumulation of pigments from homogentisic acid in the joints causes osteoarthrosis. Th...