Utilisation de l’Hydroquinone et Ochronose

Rule No: 1

• Recognize melasma (chloasma, pregnancy mask)
• Rule out the differential diagnoses:

1. lichen planus pigmentosus (darker skin patients (Indians), pigmentation is often seen behind the ears)
2. Hori’s Nevus
3. Drug-induced hyperpigmentation
4. ochronosis

Rule No: 2

If the patient reports worsening of melasma with hydroquinone use, consider seriouslsy the diagnosis of ochronosis:

• Stage 3 ochronosis is easy to recognize
• Stage one is more difficult to recognize

1. It can clinically mimick melasma
2. It is characterized by speckled appearance and feels rough on palpation
3. Dermoscopy (Dermatoscopy) can be useful to make the diagnosis

Rule No: 3

• Do not use Hydroquinone for more than 9 months. Consider changing creams if no response.
• There have been 2 case reports of ochronosis occuring after less than one year of use of Hydroquinone 2% (low concentration)… therefore it is not that rare

Contributors:

Dr Christophe HSU – dermatologist. Geneva, Switz

Source of information. Thng STG. Pigmentary Disorders. NSC Update 2012. Singapore