OCHRONOSIS is a term which was first used in 1866 by Virchow,1 who observed discoloration of various cartilages during a postmortem examination. Under the microscope, the pigment appeared pale yellow or ocher, although to the naked eye it was grayish-brown or black. Virchow's case remained unnoticed until Albrecht2 reported a second one, in 1902. The cardinal features of the disease, consisting of blackening of the cartilages, pigmentation of the skin, urine that darkens on exposure to air, and osteoarthritis were described by Osler,3 in 1904. Pick4 reported a case, in 1906, which was supposedly due to the prolonged use of phenol dressings to ulcers of the leg. Cases of exogenous ochronosis (carbolochronosis), however, have not been seen for many years.
Medical writings of the 16th and 17th centuries referred to instances of urine which was black when voided or which darkened on exposure