An epidemiological study of pityriasis rosea in Middle Road Hospital.

Pityriasis rosea is a common skin disorder seen in dermatological practices. A one year prospective study on pityriasis rosea was carried out in Middle Road Hospital, Singapore. A total of 214 patients were studied. The incidence rates by age, sex and month were analysed. The peak incidence was in the 20-24 age group. There was a male predominance. More patients with pityriasis rosea were seen in the months of March, April and November. The clinical features in our patients concur with other studies. Blood for VDRL was done on 170 patients. Two had a biological false positive test. Total white counts were normal in 97.9% of specimens done. The rash lasted from 1 to 8 weeks in 84.4% of the patients with most patients suffering from the rash for 5 weeks.