ABSTRACT
Adult onset still’s disease (AOSD) is a rare inflammatory disorder of unknown etiology. Because of lack of a defined diagnostic test the diagnosis of AOSD can only be made after excluding infectious, malignant, and autoimmune diseases. A 21-year-old female patient was admitted in our hospital with intermittent high-grade fever, polyarthritis and rash. On further history, examination and laboratory investigation she was found to be fulfilling all the Yamaguchi criteria for AOSD. All other causes consisting of acute or chronic infections, hematological malignancies, and other rheumatic disorders were excluded by laboratory investigations. Patient was treated as AOSD with non-steroidal anti-inflammatory drugs and steroids and is completely free of symptoms.