Acquired Blaschko dermatitis
The classic presentation of ABD involves a rapid onset of 1-4 mm pruritic, erythematous, edematous papules or papulovesicles that coalesce to form plaques across single or multiple lines of Blaschko. The bands are typically 2-4 cm wide, and when unilateral, there is a strict demarcation at the midline. Papules may have a fine scale. ABD typically resolves in weeks to months without treatment, though multiple recurrences may occur over the following months and years. The trunk is affected most frequently followed by the extremities, with rare involvement of the neck and face. The disease is typically seen among men and women in their fourth to fifth decade of life.
The classification of ABD has been controversial in the literature. Some authors classify it as the adult form of lichen striatus. Others view it as a separate diagnosis given its distinctive histopathology as well as the fact that typical lichen striatus cases are encountered in adults.
L30.9 – Dermatitis, unspecified
703938007 – Inflammatory dermatosis
Differential Diagnosis & Pitfalls