Search

Pityriasis rotunda is a rare disease characterized by perfectly round to oval, sharply defined, scaly, hypo/hyperpigmented patches of variable number and size located mainly over the trunk and proximal extremities. More than 95% of the reported cases in medical literature are from three countries/ethnic populations, namely Japan, South Africa (Bantu), and Italy (Sardinian islanders). To the best of my knowledge, no patient with the characteristic clinico-pathologic features has been reported from the Indian subcontinent. I report a 44-year-old man with eighteen pityriasis rotunda patches, persistent for nearly 20 years. The lesions in the groin and axillae closely resembled erythrasma and tinea, and he had received treatment for these conditions several times in the past. Histopathology of the skin biopsy showed thinning of the epidermis with a thinned-out granular layer and a sparse lymphomononuclear infiltrate in the dermis. A review of literature suggests that there are two subsets of the disease. The type I subset is comprised of pityriasis rotunda associated with systemic illness and is seen in Black or Oriental patients with no family history of the disease. The lesions tend to subside on treatment of the underlying illness. The type II subset patients are Caucasians as well as Blacks and Orientals with no underlying systemic illness. Familial occurrence is possible; lesions tend to be persistent and unresponsive to therapy.

A 2.5-year-old boy presented with skin lesions consistent with Mucha-Habermann disease, which appeared about 5 days after an injection of freeze-dried live attenuated measles vaccine. He responded to both oral and topical corticosteroid therapy. To my knowledge, this represents the first such association of Mucha-Habermann disease with virus vaccination.

We have compared the clinical and histopathological features of 6 patients with lymphomatoid papulosis (LP) and 14 patients with pityriasis lichenoides et varioliformis acuta (PLEVA). There were some differences between the clinical features in the two diseases, including the size and appearance of skin lesions and the duration of the course of disease. Ki-1 Ag positive, large, atypical, lymphoid cells were always seen in lymphomatoid papulosis; none of lymphoid cells of pityriasis lichenoides et varioliformis acuta demonstrated this antigen. We conclude that lymphomatoid papulosis and PLEVA, although sharing some common features, should be considered to be different clinical and immunopathological entities.

A 61-year-old Japanese man with chronic myelogenous leukemia developed pityriasis lichenoides-like eruptions during chemotherapy. Histopathological features were also consistent with the disease. The eruption in this case may have been an allergic reaction arising in a depressed immunity induced by chemotherapy.