Histological Evaluation of Acquired Dermal Macular Hyperpigmentation

Area of Science:

• Dermatopathology
• Histology
• Pigmentation disorders

Background:

• Acquired dermal macular hyperpigmentation (ADMH) is an umbrella term encompassing various conditions.
• Conditions include ashy dermatosis, erythema dyschromicum perstans, lichen planus pigmentosus, and idiopathic macular eruptive pigmentation.

Purpose of the Study:

• To classify patients with acquired dermal macular hyperpigmentation (ADMH) based on histological findings.
• Investigate potential correlations between clinical features and histological subtypes.

Main Methods:

• Retrospective, cross-sectional study analyzing histology specimens from ADMH patients.
• Skin biopsies collected between January 2015 and December 2017.
• Pathological review and classification of histological patterns, with correlation to clinical data.

Main Results:

• Three distinct histological patterns were identified in 30 patients.
• Pattern 1 (40%): Basal cell degeneration and inflammation.
• Pattern 2 (40%): Pigment incontinence and sparse inflammation.
• Pattern 3 (20%): Sparse inflammation without basal cell degeneration or significant pigment incontinence.
• A statistically significant association was found between age of onset and histological pattern (P=0.02).

Conclusions:

• The study identified three histological patterns within acquired dermal macular hyperpigmentation (ADMH).
• A significant association exists between the age of onset and the observed histological patterns.
• Further prospective studies are needed to determine if these patterns represent stages of a single disease or distinct entities.