title: Exogenous Ochronosis.
abstract: Exogenous ochronosis (EO) is a cutaneous disorder characterized by blue-black pigmentation resulting as a complication of long-term application of skin-lightening creams containing hydroquinone but may also occur due to topical contact with phenol or resorcinol in dark-skinned individuals. It can also occur following the use of systemic antimalarials such as quinine. EO is clinically and histologically similar to its endogenous counterpart viz., alkaptonuria, which, however, exhibits systemic effects and is an inherited disorder. Dermoscopy and in vivo skin reflectance confocal microscopy are noninvasive in vivo diagnostic tools. It is very difficult to treat EO, a cosmetically disfiguring and troubling disorder with disappointing treatment options.
authors.affiliation: Department of Dermatology, Dr. D. Y. Patil Hospital and Research Institute, Nerul, Navi Mumbai, India.
authors.forename: Prachi A
authors.initials: PA
authors.lastname: Bhattar
authors.affiliation: Skin Diseases Centre, Nashik, Maharashtra, India.
authors.forename: Vijay P
authors.initials: VP
authors.lastname: Zawar
authors.affiliation: Department of Dermatology, Dr. D. Y. Patil Hospital and Research Institute, Nerul, Navi Mumbai, India.
authors.forename: Kiran V
authors.initials: KV
authors.lastname: Godse
authors.affiliation: Department of Dermatology, Dr. D. Y. Patil Hospital and Research Institute, Nerul, Navi Mumbai, India.
authors.forename: Sharmila P
authors.initials: SP
authors.lastname: Patil
authors.affiliation: Department of Dermatology, Dr. D. Y. Patil Hospital and Research Institute, Nerul, Navi Mumbai, India.
authors.forename: Nitin J
authors.initials: NJ
authors.lastname: Nadkarni
authors.affiliation: Department of Dermatology, Dr. D. Y. Patil Hospital and Research Institute, Nerul, Navi Mumbai, India.
authors.forename: Manjyot M
authors.initials: MM
authors.lastname: Gautam
keywords: Exogenous ochronosis; hydroquinone; melasma