Question: What is (are) Adult-onset Still's disease ?
Answer: Adult-onset Still's disease is an inflammatory condition characterized by high fevers, rash, sore throat, and joint pain. As it progresses, adult-onset Still's disease may lead to chronic arthritis and other complications. Still's disease was named after an English doctor named George Still, who described the condition in children in 1896. Still's disease which occurs in children (those under the age of 16) is now known as systemic onset juvenile rheumatoid arthritis (JRA). In 1971, the term "adult Still's disease" was used to describe adults who had a condition similar to systemic onset JRA. The cause of adult-onset Still's disease is unknown. No risk factors for the disease have been identified. There's no cure for adult-onset Still's disease; however, treatment may offer symptom relief and help prevent complications.
Source: GARD

Question: What are the symptoms of Adult-onset Still's disease ?
Answer: What are the signs and symptoms of Adult-onset Still's disease? The Human Phenotype Ontology provides the following list of signs and symptoms for Adult-onset Still's disease. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of temperature regulation 90% Arthralgia 90% Arthritis 90% Hepatomegaly 90% Joint swelling 90% Leukocytosis 90% Pruritus 90% Restrictive lung disease 90% Skin rash 90% Splenomegaly 90% Urticaria 90% Abdominal pain 50% Abnormality of the pericardium 50% Abnormality of the pleura 50% Mediastinal lymphadenopathy 50% Myalgia 50% Abnormality of lipid metabolism 7.5% Abnormality of the myocardium 7.5% Bone marrow hypocellularity 7.5% Cartilage destruction 7.5% Elevated hepatic transaminases 7.5% Meningitis 7.5% Recurrent pharyngitis 7.5% The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD