Still’s disease in adults is a clinical syndrome of unknown etiology with prolonged intermittent fever, transient polymorphic rash, arthritis or arthralgia, sore throat, and systemic involvement such as increased peripheral blood leukocyte count and granulocytes and impaired liver function. It is called “allergic subsepsis” because of its clinical resemblance to sepsis or infection-induced metaplasia. Since 1995, 500 cases have been reported in the literature, and many more have not been reported, so it is a more common disease. The two nomenclatures have long been abolished internationally and domestically, and are uniformly referred to as adult Still disease, or more precisely, adult-onset Still disease. In the past, AOSD was thought to be a special type of rheumatoid arthritis, but now most people believe that the onset of AOSD, the affected population, HLA typing, joint involvement characteristics, negative anti-nuclear antibody and rheumatoid factor, and the prognosis of the disease are significantly different from rheumatoid arthritis, and they are two different diseases. Epidemiology The disease occurs in young people aged 16-35 years old, and the prevalence is basically equal in both sexes. The etiology and pathogenesis of this disease is unknown, but it is generally believed to be related to infection, genetics and immune abnormalities, probably due to the systemic immune inflammatory response of susceptible individuals to superantigens of pathogenic microorganisms (such as bacterial or viral infections), resulting in a series of inflammatory clinical manifestations such as fever, transient rash, arthralgia, and increased peripheral blood leukocytes. The main manifestations are fever, rash, arthritis (pain), and secondary manifestations are sore throat, lymph node enlargement, hepatosplenomegaly, etc. The clinical manifestations are complex and varied, often with multi-system involvement. 1. Fever is seen in almost all patients and is often the first symptom. The fever is usually sudden and high, with one peak a day (occasionally 2 peaks a day), and the temperature exceeds 39℃, mostly peaking in the afternoon or evening, and 80% of patients can have their temperature reduced to normal after a few hours or the next morning without antipyretics. The fever can last for several days or years, with recurrent episodes. However, despite the prolonged fever, the patient remains in good general condition and has no obvious toxic symptoms. 2. The rash is seen in more than 85% of patients and is manifested as a diffuse congestive red papule, mostly on the trunk, neck and proximal extremities, which is transient and leaves no trace after fading. The rash mostly appears with fever and disappears after the fever subsides. In some patients, the rash worsens or becomes obvious after mechanical stimulation such as scratching and rubbing, which is called Koebner’s sign. 3. Patients do not necessarily have arthritis, but almost 100% have arthralgia, mostly affecting large joints, with knee (84%) and wrist (74%) joints being the most common, followed by ankle, shoulder, elbow, proximal interphalangeal joints (half of patients) and metacarpophalangeal joints (1/3 of patients). Joint signs and symptoms tend to resolve with a decrease in body temperature. Most patients have no residual joint deformity after the fever subsides, and a few patients with persistent arthritis develop joint ankylosis after several years. 4. Sore throat is seen in more than half of the patients, often early in the disease and sometimes present throughout the course of the disease. The sore throat appears or worsens with fever and is relieved when the fever subsides. Pharyngeal examination shows congestion in the pharynx, hyperplasia of lymphatic follicles in the posterior pharyngeal wall, enlarged tonsils, negative pharyngeal swab culture, and ineffective antibiotic treatment. 5.Lymph node enlargement is common in the neck, axilla and groin, symmetrically distributed, soft, with light pressure pain, no adhesions, and varying in size. About half of the patients have mild to moderate splenomegaly. 6. Other rare clinical manifestations include abdominal pain, pleurisy, pneumonia, pericarditis, myocarditis, nonsuppurative meningitis, epilepsy, amyloidosis, acute liver and renal failure, diffuse intravascular coagulation, phagocytic syndrome, etc. V. Diagnosis Because of the complex and variable clinical manifestations or atypical symptoms of the disease, and the absence of specific diagnostic indicators in laboratory tests, the clinical diagnosis is difficult and can easily lead to misdiagnosis and omission. The disease should be considered in cases with three main signs: fever, rash and arthritis/arthralgia, leukocytosis and neutrophilia, increased ESR, negative blood culture, and ineffective antibiotic therapy with effective hormones. Specific diagnostic bases include: 1. prolonged recurrent fever (high fever, single peak per day) while generally in good condition, with no obvious signs of toxicity, and as usual after the fever subsides; 2. recurrent transient, polymorphic rash associated with fever; 3. arthritis/arthralgia, which may be accompanied by muscle aches and pains to the same extent as the fever peak; 4. sore throat, which appears with fever and subsides with fever; 5. enlargement of liver and spleen, lymph nodes and lung, heart, kidney, and Multi-organ damage such as plasma membrane, which can return to normal after treatment; 6. Significantly increased leukocytes and neutrophils, increased ESR and CRP, abnormal liver function, negative ANA and RF, infectious bone marrow picture, negative blood and bone marrow cultures; 7. Ineffective treatment with multiple antibiotics while responding well to hormones; 8. Other diseases can be excluded. There is no specific diagnostic method for this disease, and many diagnostic or classification criteria have been developed at home and abroad, but there is still no unified and accepted criteria. There are mainly the Cush diagnostic criteria proposed by American scholars and the Yamaguchi diagnostic criteria proposed by Japanese scholars. Treatment Acute phase About 1/4 patients respond well to non-steroidal anti-inflammatory drugs (NSAID), and these patients tend to have a better prognosis. High-dose enteric aspirin and indomethacin were commonly used before the advent of selective cyclooxygenase-2 (COX-2) inhibitors. NSAIDs may be used alone in mild cases, such as naproxen 0.2 g twice daily, indomethacin 25 mg three times daily, and fotarolimus 25-60 mg three times daily. Side effects such as hepatotoxicity and intravascular coagulation should be noted during the use of NSAIDs. Systemic glucocorticosteroids should be used in the following cases: 1) poor NSAID efficacy or toxic side effects such as hepatic impairment or relapse after dose reduction; 2) severe conditions such as pericardial tamponade, myocarditis, severe pneumonia, intravascular coagulation and severe damage to other organs. Usually the hormone dose is prednisone 0.5~1mg/Kg/d, gradually reduce the dose after the symptoms improve, the total course of treatment should not exceed 6 months, the reduction process can be added with non-steroidal drugs to consolidate the efficacy, the poor efficacy or critical condition can be treated with high-dose methylprednisolone shock. Chronic phase The main problem is arthritis. Palliative agents (including gold, hydroxychloroquine, salazosulfapyridine and penicillamine) can help control arthritis and other chronic systemic lesions. Immunosuppressive agents such as azathioprine, cyclophosphamide, and cyclophilin may be used in recalcitrant cases. After 10 years of disease onset, about half of the patients still require palliative medications, and 1/3 of them also require concomitant low-dose hormones. Most of the patients have a good prognosis. 1/5 patients have remission within 1 year and no recurrence. 1/3 patients have complete remission after several recurrent episodes, and the time of recurrence is variable, but the symptoms are often milder and shorter in recurrence than in the first episode. The rest of the patients have a chronic course, mainly chronic arthritis, and a few may progress to severe joint destruction, which may lead to joint ankylosis and even joint replacement. Polyarthritis (≥4 joints involved) or involvement of the foot, shoulder and hip joints tend to become chronic. In addition, those with childhood onset requiring systemic hormone therapy for more than 2 years also tend to have a poor prognosis. Causes of death include acute liver failure, diffuse intravascular coagulation, secondary amyloidosis, and sepsis.