Lichen planus pigmentosus - An appraisal

A Delphi consensus on the nomenclature and diagnosis of lichen planus pigmentosus and related entities

BACKGROUND

Although well known in clinical practice, research in lichen planus pigmentosus and related dermal pigmentary diseases is restricted due to lack of consensus on nomenclature and disease definition.

AIMS AND OBJECTIVES

Delphi exercise to define and categorise acquired dermal pigmentary diseases.

METHODS

Core areas were identified including disease definition, etiopathogenesis, risk factors, clinical features, diagnostic methods, treatment modalities and outcome measures. The Delphi exercise was conducted in three rounds.

RESULTS

Sixteen researchers representing 12 different universities across India and Australia agreed to be part of this Delphi exercise. At the end of three rounds, a consensus of >80% was reached on usage of the umbrella term 'acquired dermal macular hyperpigmentation'. It was agreed that there were minimal differences, if any, among the disorders previously defined as ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis and pigmented contact dermatitis. It was also agreed that lichen planus pigmentosus, erythema dyschromicum perstans and ashy dermatosis did not differ significantly apart from the sites of involvement, as historically described in the literature. Exposure to hair colours, sunlight and cosmetics was associated with these disorders in a significant proportion of patients. Participants agreed that both histopathology and dermatoscopy could diagnose dermal pigmentation characteristic of acquired dermal macular hyperpigmentation but could not differentiate the individual entities of ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis, lichen planus pigmentosus and pigmented contact dermatitis.

LIMITATIONS

A wider consensus involving representatives from East Asian, European and Latin American countries is required.

CONCLUSION

Acquired dermal macular hyperpigmentation could be an appropriate conglomerate terminology for acquired dermatoses characterised by idiopathic or multifactorial non-inflammatory macular dermal hyperpigmentation.

Acquired Dermal Macular Hyperpigmentation: An Update

Acquired dermal macular hyperpigmentation (ADMH) is an umbrella term that includes disorders clinically characterized by small and large pigmented macules/patches and histopathologically showing an evidence of current or resolved interface dermatitis with pigment incontinence, without clinically significant prior inflammatory phase. The term intends to include diseases previously described in the literature as lichen planus pigmentosus, Riehl's melanosis/pigmented cosmetic dermatitis and ashy dermatosis/erythema dyschromicum perstans. The nomenclature and origin of these disorders have always been a matter of discussion. These disorders share many clinicopathological similarities, are difficult to treat and adversely affect the quality of life. Recent consensus points towards the need for a unifying term to facilitate research and therapeutic trials. This article aims to provide a comprehensive review of the recent advances in ADMH.

Acquired brachial cutaneous dyschromatosis

Acquired brachial cutaneous dyschromatosis (ABCD) is a relatively newly described, acquired disorder of pigmentation characterized by geographic-shaped, gray-brown, hyperpigmented patches and interspersed with hypopigmented macules, involving the dorsal aspects of the forearms in postmenopausal women. There is a suggested relationship with hypertension and antihypertensive medication intake, specifically angiotensin-converting enzyme inhibitors, or a cumulative effect of sun damage, as possible triggers. ABCD is benign, asymptomatic, and more of an esthetic concern. Topical depigmenting agents, chemical peels, and laser therapy may be helpful.