Exogenous ochronosis in Asians

Exogenous ochronosis is an infrequent dermatosis characterized by dark blue hyperpigmentation. It may be caused largely by hydroquinone, a fenolic compound which is used in the treatment of melasma and other skin hyperpigmentation. The exact etiopathology is still not understood and the results of various treatments offered are unsatisfactory. We present a case of exogenous ochronosis which resembled melasma but clinicopathologic evaluation led to the correct diagnosis. We also emphasize the need to restrict the indiscriminate use of hydroquinone containing compounds without medical prescription.

International Journal of Advances in Medicine

Exogenous ochronosis is an infrequent skin disorder characterised by bluish-black or grayish brown pigmentation on dermis. It is the most common condition caused due to long term application of Hydroquinone skin preparations for melasma, skin brightening, cholasma, acne induced pigmentation etc. This report refers to a case of 39-year-old female patient who presented to the hospital with chief complaints of progressive formation of dark lesions over face, neck since one and half-year. She had history of usage of hydroquinone (4%) cream for skin brightening for a period of three months. Based on clinical findings and history she was diagnosed to have acquired exogenous ochronosis and was treated with microdermabrasion, cosmelan peel, yellow peel, glutathione tablets, topical sunscreen and kojic acid cream. Patient noted 50% improvement in her condition after 4 months of treatment. It is believed that application of high concentrations of hydroquinone for a prolonged period causes exo...

Singapore Medical Journal, 2014

The term 'ochronosis' was first coined by Virchow in 1866 to refer to brownish-yellow accumulations of pigment found in the connective tissue of patients with endogenous ochronosis. (1) Endogenous ochronosis, also known as alkaptonuria, is a rare (1:250,000) autosomal recessive disease caused by the congenital absence of homogentisic acid oxidase, leading to the accumulation of homogentisic acid within various tissues of the body. (2) Cutaneous features of endogenous ochronosis include blue-black hyperpigmentation on the pinnae, nasal tip, cheeks, sclerae and axilla. Systemic deposition of homogentisic acid results in ochronotic arthropathy (mainly involving large joints and the vertebral column), deafness, genitourinary obstruction and cardiovascular complications (e.g. aortic valve calcification and stenosis). Diagnosis is usually made clinically or with urine tests using sodium hydroxide. Exogenous ochronosis was first described by Pick in 19 06. (3) This condition is often reported in the black population of South Africa as a result of the use of bleaching agents, particularly hydroquinone. (4) Other agents implicated include antimalarials, and products containing resorcinol, phenol, mercury or picric acid. (5) Classical features of exogenous ochronosis are asymptomatic blue-black macules with textural coarsening and sooty tipped papulations on the malar area, temples, inferior cheeks and neck. In 1979, Dogliotti et al (6) classified exogenous ochronosis into three clinical stages: (a) erythema and mild hyperpigmentation; (b) hyperpigmentation, pigmented colloid milium (i.e. caviar-like lesions) and scanty atrophy; and (c) papulonodular lesions. Recently, Tan (7) described a case series of exogenous ochronosis in the Chinese population. In that study, Tan highlighted that the actual prevalence of the condition in the Chinese population was likely to be higher than that reported,

Trakia Journal of …, 2005

The formally accepted meaning of the term ochronosis is musculoskeletal and skin manifestation of alkaptonuria. Additionally, exogenous ochronosis has been reported following long-term application of skin-lightening creams, which contain hydroquinone, phenol or resorcinol. It exclusively affects black individuals, particularly in South Africa, but with an increasing number of reports on a worldwide scale.

2005

The formally accepted meaning of the term ochronosis is musculoskeletal and skin manifestation of alkaptonuria. Additionally, exogenous ochronosis has been reported following long-term application of skin-lightening creams, which contain hydroquinone, phenol or resorcinol. It exclusively affects black individuals, particularly in South Africa, but with an increasing number of reports on a worldwide scale. We describe a 57-year-old female patient with

Journal of Orthopaedic Experience & Innovation

Ochronosis is a rare disease characterized by skin pigment changes and degenerative arthritis caused by deposition of homogentisic acid in joint cartilage. There are exogenous and endogenous forms of the disease with the endogenous form typically caused by alkaptonuria, or a defect in homogentisic acid oxidase enzyme. In this report we present a previously undocumented case of endogenous ochronosis caused by topical hydroquinone use in a 69-year-old Caucasian male without alkaptonuria.

Archives of Dermatology, 2010

Background: Exogenous ochronosis presents as an acquired asymptomatic hyperpigmentation on photoexposed areas, predominantly over bony prominences, and is caused by the topical application of several skinlightening agents. Observations: We describe a 63-year-old Hispanic woman who developed exogenous ochronosis lesions on her face after using topical bleaching creams containing hydroquinone, 2% to 3%, and oxybenzone, 2%, for several years. Dermoscopy revealed irregular brown-gray globular, annular, and arciform structures that corresponded to focal deposition of ochronotic pigment on the dermis. These deposits correlated with multiple bananashaped nonrefractile structures seen using reflectance confocal microscopy. Histopathologic sections revealed the deposition of a banana-shaped, yellow to brown material in the papillary and middle dermis. Ultrastructural

Journal of Clinical Research in Dermatology, 2020

Melasma is a hyperpigmented lesion that occurs on different skin areas that are often exposed to sunlight with predilection arising on the face, neck, and partially on arms or other body parts. It is also known as chloasma or black colour. This pigmentation disorder is common to people with IV-VI type of skin, and those living in the environment with more Ultraviolet (UV) exposure. Yet, its etiology has not been understood clearly. The major influential factors on its pathogenesis are UV radiation exposure, endocrine factor, genetic predisposition, the phototoxic/ photoallergies medicine,anticonvulsant medicine,particularly cosmetics, and nutrition deficiency are reportedly less influential or a rare factor. The aim of this research is to prove the difference between melanin index number on melasma patients having therapies by using non-hydoquinone cream and Kligman’s formula.

2022

While many scholars have discussed the unique quality of Dimitris Pikionis’ work as a result of its materiality, few scholars have focused on this work’s materialization. Based on unpublished archival material I will focus on the construction of Pikionis’ Acropolis Works in order to argue in favor of a critique of building construction, rather than the usual consideration of architectural form. A view on the microhistory of the specific project’s construction can make for a factual, transparent and responsible form of criticism, one that casts light to the broader social, political, and cultural aspects of modernity.

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