ochronosis


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ochronosis

 [ok″ro-no´sis]
a peculiar discoloration of body tissues caused by deposit of alkapton bodies as the result of a metabolic disorder.
ocular ochronosis brown or gray discoloration of the sclera, sometimes involving also the conjunctivae and eyelids.

o·chron·o·sis

(ō'kron-ō'sis),
A rare, autosomal recessive disease characterized by alkaptonuria with pigmentation of the cartilages and sometimes tissues such as muscle, epithelial cells, and dense connective tissue; may affect also the sclera, mucous membrane of the lips, and skin of the ears, face, and hands, and cause standing urine to be dark colored and contain pigmented casts; pigmentation is thought to result from oxidized homogentisic acid, and cartilage degeneration results in osteoarthritis, particularly of the spine.
[G. ōchros, pale yellow, + nosos, disease]

ochronosis

/ochro·no·sis/ (o″kron-o´sis) deposition of dark pigment in the body tissues, usually secondary to alkaptonuria, characterized by urine that darkens on standing and dusky discoloration of the sclerae and ears.ochronot´ic

ochronosis

[ō′krənō′sis]
Etymology: Gk, ochros, yellow, osis
an inherited error of protein metabolism characterized by an accumulation of homogentisic acid, resulting in degenerative arthritis and brown-black pigment deposited in connective tissue and cartilage. It is often caused by alkaptonuria or poisoning with phenol. Bluish macules may be noted on the sclera, fingers, ears, nose, genitalia, buccal mucosa, and axillae. Urine color may be dark. See also alkaptonuria.
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Ochronosis

ochronosis

Alkaptonuria, see there.

o·chro·no·sis

(ō'kron-ō'sis)
A condition observed in people with alkaptonuria, characterized by pigmentation of the cartilages; also may affect the sclerae, mucous membrane of the lips, and skin of the ears, face, and hands and may cause standing urine to be dark and contain pigmented casts; pigmentation results from oxidized homogentisic acid; cartilage degeneration results in osteoarthritis.
[G. ōchros, pale yellow, + nosos, disease]

ochronosis

Persistent joint disease associated with blue or brownish discoloration of the joint cartilages occurring in patients with ALKAPTONURIA.

ochronosis

People with this rare hereditary condition tend to develop arthritis in adulthood.
Mentioned in: Pseudogout

ochronosis (ōˈ·kr·nōˑ·sis),

n condition marked by accumulation of black-brown pigment in cartilage, joint capsules, and other connective tissues as a result of alkaptonuria, which is a metabolic disorder resulting in accumulation of homogentisic acid. See also alkaptonuria.

ochronosis

a yellow, brown or chocolate discoloration of cartilage, tendon sheaths and ligaments but not bone. Caused by deposit of alkapton bodies as the result of a metabolic disorder. Affected parts must be condemned as not suitable for human consumption.

ocular ochronosis
brown or gray discoloration of the sclera, sometimes involving also the conjunctivae and eyelids.
References in periodicals archive ?
Biochemical, pathologic and clinical aspects of alcaptonuria, ochronosis, and ochronotic arthropathy.
Even though, to the best of my knowledge, there has never been a credible published research finding which has made a causal link between genetic predisposition and the chance of getting exogenous ochronosis with hydroquinone, medical literature on the issue published in the United States has often suggested a racially-based genetic link between skin-bleaching and exogenous ochronosis.
To back up my claim I have selected three articles on the topic of skin-bleaching and exogenous ochronosis published in three different but comparable professional journals in the field of dermatology.
Second, to make the case for their preferred alternative explanation, that there is a link between black genetic predisposition and getting exogenous ochronosis, the authors have denied a link between carcinogenic effects associated with the use of hydroquinone-based skin-bleaching agents and getting exogenous ochronosis by saying that, "Despite the widespread use of similar hydroquinone bleaching creams in the United States, there has been only one previously published report of a similar reaction occurring in this country.
The patient certainly, had none of the stigma of advanced ochronosis, that is, pigmented papules, milia, and nodules.
It concerns a Mexican-American woman who had suffered from a severe case of exogenous ochronosis after using over-the-counter 2 percent hydroquinone skin-bleaching cream for a period of six months.
As a result, the authors have used this woman's negative experience with hydroquinone to make a causal link between the use of hydroquinone based skin-bleaching agents and a supposed black genetic predisposition to getting exogenous ochronosis.
Exogenous ochronosis, or hyperpigmentation resembling ochronosis, is a syndrome of cutaneous pigment deposition associated with the topical application of various agents including hydroquinone, phenol, resorcinol, and picric acid, as well as both parenteral and intramuscular antimalarial drugs.
The supposed black genetic predisposition to getting exogenous ochronosis and similar skin conditions in the presence of skin-bleaching chemicals such as hydroquinone have been more in the minds of the mainly white western medical establishment than in the genes of black subjects.
Exogenous ochronosis and pigmented colloid millium from hydroquinone bleaching creams.
This case expands the list of conditions that may result in increased dural pigmentation to include ochronosis.
Alcaptonuria, ochronosis, arthritis and ruptured intervertebral disc complicated by homologous serum reaction.