Dowling-Degos disease--a heat aggravated variant

Area of Science:

• Dermatology
• Genodermatoses
• Medical Genetics

Background:

• Dowling-Degos disease (DDD) is a rare genodermatosis characterized by reticulate hyperpigmentation, often with follicular papules and pitted scars.
• Its clinical spectrum can be variable, and variants may present with overlapping features with other genodermatoses.
• Heat and humidity are known to exacerbate certain dermatological conditions.

Observation:

• A 22-year-old woman presented with a 5-year history of a heat-aggravated micropapular eruption on her limbs and reticulate pigmentation on her neck and chest.
• The eruption, associated with pruritus, worsened in summer, with papules noted in intertriginous areas but lacking pigmentation.
• Histopathology revealed characteristic epidermal changes with club- and antler-like rete ridges, but notably absent acantholysis or dyskeratosis.

Findings:

• The patient's distinct clinical presentation, particularly the heat aggravation and specific histopathological findings, suggests an unusual variant of Dowling-Degos disease.
• The condition shares clinical features with Darier's disease and transient acantholytic dermatosis, complicating initial diagnosis.
• The absence of acantholysis and dyskeratosis in biopsies differentiates it from some other genodermatoses.

Implications:

• This case expands the known clinical spectrum of Dowling-Degos disease, emphasizing the importance of considering variants in atypical presentations.
• Recognizing this heat-aggravated variant is crucial for accurate diagnosis and management of patients with similar dermatological findings.
• Further research into the genetic and molecular basis of such variants could improve understanding and treatment of genodermatoses.