Pityrosporum folliculitis presents as fine superficial follicular pustules and papules on the trunk and upper extremities. Ketoconazole 2% foam was recently approved for the treatment of seborrheic dermatitis in immunocompetent patients 12 years and older. Ketoconazole 2% foam is felt to work by reducing the number of pityrosporum yeast organisms. Safety and efficacy of ketoconazole 2% foam treatment for this fungal infections has not been established. This study is to demonstrate efficacy and safety in the treatment of pityrosporum folliculitis.