A Patient With Blue Ears

Alkaptonuria with asymmetric otologic involvement: a case report

“…Alkaptonuria has three distinct features which are homogentisic aciduria, ochronotic osteoarthropathy, and ochronosis. 3 Each feature presents at a different stage in life. Homogentisic aciduria is present at birth and can lead to early diagnosis by the darkening of the urine in infancy.…”

“…Homogentisic aciduria is present at birth and can lead to early diagnosis by the darkening of the urine in infancy. 3 Ochronosis, which occurs secondary to polymerization of HGA, appears between the third and fifth decade of life with melanin-like pigment deposition in the ears and eyes. 1 Ochronotic osteoarthropathy arises about the fourth decade and mostly affects the large weight-bearing joints, such as the knees, leading to changes similar to osteoarthritis radiographically.…”

“… 7 The vertebrae are also often affected, with osteophyte formation and stiffening of the intervertebral joints. 3 Furthermore, affected patients are at an increased risk of bone fractures, nephrolithiasis, prostate stones, and valvular heart disease. 8 …”

“… 2 The consequent increase in levels of HGA causes polymerization and accumulation of a melanin-like pigment that is selectively deposited in connective tissues. 3 This pigment has a high affinity for skin, bone, and mucosal surfaces, hyaline cartilages, intervertebral discs, skin, sclera, and the concha and helix of the ear. 4 , 5 Otologic involvement has previously been described by one study and limited number case reports.…”