Cutaneous pseudolymphoma at the site of prior herpes zoster eruption.

A 55-year old woman with a history of herpes zoster in the dermatome supplied by the mandibular branch of the trigeminal nerve developed cutaneous red papules and umbilicated nodules within the same segment. The clinical and histological diagnosis was pseudolymphoma. The lesions showed a polymorphous infiltrate without germinal center formation. Immunologic phenotyping with monoclonal antibodies revealed the predominance of helper T cells and distinct compartmentalization of B and T cells. The lesions healed up within 7 weeks. The development of pseudolymphomas at the site of previous herpes zoster eruptions seems to be extremely rare.