Papular acrodermatitis of childhood (PAC), first recognized in Milan and described by Gianotti in 1955, is an infectious disease of childhood, of low infectivity, fairly widespread, and characterized by: (1) Non-relapsing erythemato-papular dermatitis localized to the face and limbs, lasting about 3 weeks. (2) Paracortical hyperplasia of lymph-nodes. (3) Acute hepatitis, usually anicteric, which lasts at least 2 months and may progress to chronic liver disease.