Table 1. Diagnostic criteria for AOSD by Yamaguchi et al.
| Major criteria | 1. Fever (≥ 39°C or higher ≥ 1 wk) 2. Arthralgias lasting ≥ 2 wk 3. Typical rash a 4. Leukocytosis (≥ 10,000/mm 3 or more) including 80% more of granulocytes |
| Minor criteria | 1. Sore throat 2. Lymphadenopathy and/or splenomegaly 3. Liver dysfunction b 4. Absence of RF and ANA |
Abbreviations: ANA, antinuclear antibody; AOSD, adult-onset Still's disease; RF, rheumatoid factor.
Notes: Diagnosis of AOSD necessitates the fulfillment of five or more criteria, of which at least two must be major. Additionally, it is imperative to exclude other clinical conditions that may present with similar symptoms to AOSD.
Rash identification: The characteristic rash of AOSD, a macular or maculopapular nonpruritic salmon-pink eruption, typically accompanies fever.
Liver dysfunction assessment: Defining liver dysfunction involves elevated transaminase and/or lactate dehydrogenase levels not attributable to drug allergies, toxicity, or other liver conditions. Prior to applying this criterion, it is advisable to assess whether liver function normalizes after stopping any hepatotoxic medications, thereby ruling out drug-induced effects.