Acropustulosis repens.

Area of Science:

• Dermatology
• Clinical Medicine

Background:

• Pustular eruptions on fingers and toes, termed acropustulosis, are often grouped under Hallopeau's acrodermatitis continua, a severe, persistent condition.
• A milder, distinct form of acropustulosis with a benign course, characterized by remissions and relapses, requires differentiation from the severe form.

Observation:

• Six patients with a mitigated form of acropustulosis, not meeting Hallopeau's criteria, were observed.
• Lesions were few, sometimes solitary, sterile pustules on the hyponychium or nail bed, leading to onycholysis.

Findings:

• The condition exhibits sterile, subcorneal pustules with neutrophils, typically on the hyponychium or nail bed.
• Lesions recur in flares with complete recovery between episodes; histopathology reveals non-spongiform pustules.
• Long-term follow-up showed benign outcomes, though one patient developed psoriasis.

Implications:

• Establishing diagnostic criteria to distinguish this benign acropustulosis from Hallopeau's acrodermatitis continua is crucial for accurate diagnosis and management.
• Recognizing this distinct entity, potentially similar to "dermatitis repens," aids in understanding its benign prognosis and treatment approach.