Exogenous ochronosis and pigmented colloid milium from hydroquinone bleaching creams.

An outbreak of ochronosis and colloid milium is described after the use of strong hydroquinone bleaching creams. These phenomena developed only after a few years, and took place when the melanocytes had overcome the bleaching influence. Sun-exposure and thorough inunction of the cream were required for the more advanced changes. Analogous changes have been seen when the skin is exposed to certain crude fuels in individuals working in the sun, and phenolic components in the fuels are suspected. The study presented here covers the clinical, histological, histochemical, electron microscopical and pathogenetic features as seen in thirty-five cases of hydroquinone damage to the dermis in South Africa.