Approach to a patient of facial hyperpigmentation

Area of Science:

• Dermatology
• Cutaneous Medicine

Background:

• Facial hyperpigmentation is a common concern, often treated with topical agents.
• Hydroquinone is a widely used depigmenting agent, but prolonged or unsupervised use can lead to adverse effects.
• Exogenous ochronosis (EO) is a rare complication characterized by blue-black or brown-black pigmentation.

Purpose of the Study:

• To report a case of exogenous ochronosis secondary to unsupervised hydroquinone use.
• To highlight the diagnostic utility of dermoscopy in identifying EO.
• To discuss management strategies for hydroquinone-induced exogenous ochronosis.

Main Methods:

• A case study of a middle-aged male patient with an 8-year history of facial pigmentation.
• Clinical examination and dermoscopic evaluation of facial lesions.
• Histopathological examination of a skin biopsy to confirm the diagnosis.

Main Results:

• The patient presented with progressive, symmetrical brown-black macules on the cheeks, malar, and temporal regions.
• Dermoscopy revealed characteristic findings including irregular globules and 'worm-like' structures.
• Skin biopsy confirmed exogenous ochronosis with ochre-coloured, banana-shaped pigment deposits in dermal collagen.

Conclusions:

• Prolonged, unsupervised application of hydroquinone cream can lead to exogenous ochronosis.
• Dermoscopy is a valuable non-invasive tool for the early recognition of exogenous ochronosis, distinguishing it from melasma.
• Management involves discontinuing hydroquinone, strict photoprotection, topical retinoids, and potentially laser therapy.