A Rare Differential Diagnosis for Acute Urticarial Plaques: Adult Onset Still's Disease

Adult-onset Still's disease (AOSD) was first described by Bywaters as a different clinical entity from Juvenile Rheumatoid Arthritis (Still's Disease). It is an uncommon, acute, systemic inflammatory disease of unknown etiology, which is characterized by a high spiking fever (>= 39 degrees C), typical skin rash with an evanescent salmon-pink erythema, leukocytosis, arthritis/arthralgia, hepatosplenomegaly, lymphadenopathy, leukocytosis, sore throat and serositis. We report two patients in whom urticaria-like rash and angioedema were uncommon presenting features of AOSD where treatment was attempted with antihistamines and systemic steroids. AOSD should be kept in mind in persistent urticarial skin rash with accompanying spiking fever.