History:

Acne necrotica varioliformis -- Itchy but scaring follicular rash involving the frontal scalp and forehead at the scalp margin. It is a deep destructive lymphocytic folliculitis. In early lesions you get a superficial neutrophilic folliculitis with intra epidermal vesicles a priminent superficial and deep perivascular and perifollicular lymphocytic infiltrate and sometimes marked sub epidermal oedema.

Later lesions show confluent necrosis of follicles, with necrotic keratinocytes within follicles and dermal fibrosis BUT no granuloma formation.