Ochronosis is the bluish-black discoloration of certain tissues, such as the ear cartilage and the ocular tissue, seen with alkaptonuria , a metabolic disorder. (medscape.com)
Alkaptonuria is a rare genetic disorder in which there is a deficiency of the enzyme homogentisic acid oxidase, resulting in the accumulation of homogentisic acid and a characteristic blue-black discoloration of the skin and cartilage, called ochronosis. (medscape.com)
Ochronosis was defined by Virchow who histologically described the connective tissue in alkaptonuria, given the cartilage's ochre, or yellow, hue under the microscope. (medscape.com)
Alkaptonuria is a rare autosomal recessive metabolic disorder caused by deficiency of homogentisic acid oxidase, the only enzyme capable of catabolizing homogentisic acid (HGA). (medscape.com)
Alkaptonuria features a defect in the biochemical pathway by which phenylalanine and tyrosine are normally degraded into fumaric and acetoacetic acid. (medscape.com)
Alkaptonuria (AKU) is a rare autosomal recessive condition with a prevalence of 1 in 250 000-1 000 000 1 caused by the deficiency of homogentisate 1,2 dioxygenase, the enzyme responsible for breaking down homogentisic acid (HGA). (bmj.com)
Nitisinone blocks the production of homogentisic acid, which accumulates in alkaptonuria and forms polymers that bind to and destroy connective tissue. (nih.gov)
Untangling the Spirals of Metabolic Disease: Primary Diagnoses and Secondary Effects: Implications for Treatment David A. H. Whiteman MD 1909 Archibald Garrod In his paper, Inborn Errors of Metabolism, the disease Alkaptonuria (Ochronosis: Homogentisic Acid Oxidase Deficiency) is described as being caused by a gene. (abcdocz.com)
Alkaptonuria ( black urine disease , alcaptonuria or ochronosis ) is a rare inherited genetic disorder of tyrosine metabolism. (wikidoc.org)
A distinctive characteristic of alkaptonuria is that ear wax exposed to air turns red or black (depending on diet) after several hours because of the accumulation of homogentisic acid. (wikidoc.org)
Deficiency1
The phenotype of acid sphingomyelinase deficiency (ASMD) occurs along a continuum. (beds.ac.uk)
Exogenous ochronosis is an avoidable dermatitis that can be caused by the topical application of compounds such as hydroquinone or phenols. (wikipedia.org)
Hydroquinone-induced exogenous ochronosis was found in 1975 by Findlay, who observed the condition in patients who used skin lightening creams containing the compound. (wikipedia.org)
Ochronosis occurs because of deposition of phenols (such as homogentisic acid and hydroquinone) as plaques in the matrix of cartilage. (wikipedia.org)
Hydroquinone can work well for Ochronosis in the same way it works for Melasma. (ncddr.org)
Exogenous ochronosis and pigmented colloid milium from hydroquinone bleaching creams. (medscape.com)
Zawar VP, Mhaskar ST. Exogenous ochronosis following hydroquinone for melasma. (medscape.com)
Exogenous ochronosis, in which bluish black pigmentation of cartilage is noted iatrogenically by exogenous agents, has been seen after exposure to noxious substances, including phenol, trinitrophenol, benzene, and hydroquinone. (medscape.com)
Alcaptonuria1
Homogentisic acid is completely absent from both urine and blood plasma if the individual does not have Alcaptonuria. (hxbenefit.com)
Enzyme homogentisic1
This is an autosomal recessive trait that is caused by a defect in the enzyme homogentisic acid oxidase ( EC 1.13.11.5 ). (wikidoc.org)
The three clinical stages of exogenous ochronosis are: Erythema and mild hyperpigmentation Hyperpigmentation and "caviar-like" lesions Papulonodular lesions Skin: The pigment is deposited throughout the skin, but only becomes apparent in certain locations, where the concentration is great enough to be seen clinically. (wikipedia.org)
In exogenous ochronosis, the hyperpigmentation is localized to the area where the inciting agent is applied. (wikipedia.org)
Symptoms of exogenous ochronosis include: Yellow-brown, banana-shaped fibers Caviar-like papules Brown-grey or blue-black hyperpigmentation Most of the lesions are seen on areas of the body that get the most sun. (wikipedia.org)
Bruce S, Tschen JA, Chow D. Exogenous ochronosis resulting from quinine injections. (medscape.com)
Bongiorno MR, Aricò M. Exogenous ochronosis and striae atrophicae following the use of bleaching creams. (medscape.com)
Urine9
This disturbance causes an accumulation and increased renal excretion of homogentisic acid (AHG), which manifests as dark urine when it oxidizes on contact with air. (cdlib.org)
Of the following, the MOST appropriate laboratory study to obtain is A. B. C. D. E. leukocyte lysosomal enzyme activities plasma long-chain fatty acid levels serum carnitine level urine for reducing substances urine organic acid levels A 3-month-old infant who has a history of gastroesophageal reflux has had increasing vomiting for 2 days. (abcdocz.com)
Homogentisic acid is also excreted in urine, making the urine turn dark when exposed to air. (medlineplus.gov)
He discovered that the substance responsible for black urine was homogentisic acid , which is present in high amounts and secreted into the urine in AKU patients. (istudy.pk)
Due to these factors, the homogentisic acid, along with its oxide named alkapton, starts accumulating in the blood of patients and are passed in considerable amounts with urine. (hxbenefit.com)
The acid is also passed along with urine which makes the urine turn dark once exposed to air. (hxbenefit.com)
Urinalysis and blood tests are performed to detect any sign of homogentisic acid in the patient's urine. (hxbenefit.com)
The enzyme normally breaks down a toxic tyrosine byproduct, homogentisic acid (also called alkapton), which is harmful to bones and cartilage and is excreted in urine. (wikidoc.org)
One of its important characteristic is Ochronosis , a condition that leads to dark pigment accumulation in connective tissues like cartilage and skin. (hxbenefit.com)
He linked ochronosis with the accumulation of alkaptans in 1902, [1] and his views on the subject were summarised in a 1908 Croonian lecture at the Royal College of Physicians . (wikidoc.org)
the amino acids phenylalanine and tyrosine, which are important building blocks of proteins. (medlineplus.gov)
As a result, a substance called homogentisic acid, which is produced as phenylalanine and tyrosine are broken down, accumulates in the body. (medlineplus.gov)
This enzyme plays an important role in breaking down the important protein building blocks tyrosine and the amino acids phenylalanine. (hxbenefit.com)
Consequently, the homogentisic acid that is produced as tyrosine and phenylalanine (that are broken down) builds up inside the body. (hxbenefit.com)
Reducing intake of the amino acids phenylalanine and tyrosine to the minimum required to sustain health (phenylalanine is an essential amino acid) can help slow the progression of the disease. (wikidoc.org)
Acidura1
Family history is the only known risk factor for Homogentisic Acidura. (hxbenefit.com)
Amino1
Phenylketonuria (PKU) Phenylketonuria is a disorder of amino acid metabolism that causes a clinical syndrome of intellectual disability with cognitive and behavioral abnormalities caused by elevated serum phenylalanine. (msdmanuals.com)
The genetic defect is autosomal recessive and is mapped to the HGO gene on arm 3q1, and 18 genetic missense mutations are known to cause homogentisic acid oxidase aberrations. (medscape.com)
Pigment1
Ochronosis, a buildup of dark pigment in connective tissues such as cartilage and skin, is also characteristic of the disorder. (medlineplus.gov)
Buildup1
The homogentisic acid buildup in tissues and cartilage leads to several serious symptoms and health problems. (hxbenefit.com)
Occurs1
Deposition also occurs at non-collagenous sites, suggesting that factors other than the presence of HGA in the tissues may favour or promote ochronosis. (bmj.com)
Tissues2
Ochronosis is the pigmentation of connective tissues and this pigmentation leads to degenerative changes in alkaptonuric patients. (qxmd.com)
The excessive homogentisic acid and other similar compounds accumulate in the connective tissues, leading to darkening of the cartilage and skin. (hxbenefit.com)
a) Light chemical peels that use a moderate solution such as alpha hydroxy acid, glycolic acid, or fruit enzymes. (28cubed.com)
Condition1
Ochronosis is another skin condition that creates an uneven skin tone . (ncddr.org)
Dark1
They also decrease or reduce discolouration, age spots, or blotchiness by exfoliating the top layer of skin as well as the dark spots with glycolic acid and salicylic acid, which speeds up the skin lightening process. (28cubed.com)
Disease1
Over the years, section members have defined the basic defects in cystinosis, Salla disease, infantile free sialic acid storage disease and sialuria, and have identified the genes responsible for Hartnup disease, 3-methylglutaconic aciduria type III, HPS-2, HPS-3 and HPS-9. (nih.gov)
Muscle1
sialic acid is necessary for muscle function because it interacts with the critical muscle protein, alpha-dystroglycan. (nih.gov)