This picture shows the knee of a person with a chronic inflammatory disease known as dermatitis herpetiformis. It produces red, raised (papular), small or large blisters (vesicles or bullae) that burn and itch intensely. Dermatitis herpetiformis develops suddenly, lasts for weeks to months, and may be associated with digestive diseases (such as Celiac disease).
Review Date 2/6/2022
Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.