Using Dermoscopy To Recognize Hydroquinone-Induced Exogenous Ochronosis
Diagnostic utility of dermatoscopy in hydroquinone-induced exogenous ochronosis. Mishra SN, Dhurat RS, Deshpande DJ, Nayak CS. Int J Dermatol. 2012 Feb 20. doi: 10.1111/j.1365-4632.2011.05305.x.
- Hydroquinone is a phenolic molecule given in various concentrations for the treatment of hyperpigmentary disorders such as melasma (chloasma) (pregnancy mask). It is also used as a whitening agent even though this is off-label and dangerous.
- Exogenous ochronosis is a known side effect which occurs with hydroquinone usage. Because of this among other toxic effects, this ingredient has been banned as a prescription drug in Europe.
- Hydroquinone prescribers should be aware of the diagnostic criteria of exogenous ochronosis in order to stop it if it occurs. Dermoscopy (or dermatoscopy) is a tool used by dermatologists and can be used in the diagnosis of numerous skin conditions.
- The authors of this paper report three patients with melasma (chloasma) (pregnancy-mask) under hydroquinone developing gray-brown or blue-black hyperpigmentation accompanied by hyperchromatic caviar-like papules over the malar region. These lesions are clinically compatible with exogenous ochronosis. “Banana-shaped” * dermal figures were found on histology which is also compatible.
- With dermoscopy such lesions show exageration of the normal facial pigment network accompanied with amorphous pigmented structures obliterating the follicular openings.
- Therefore physicians competant in the treatment of pigmentary disorders should be able to distinguish exogenous ochronosis from melasma and stop hydroquinone before irreversible facial scarring takes place.
*short arciform structures are described on dermoscopy.
