Adult-onset Still disease

Differential Diagnosis

• Infection:
  • Viral: HIV, herpesviruses, measles, rubella, viral hepatitis, parvovirus B19
  • Bacterial: borreliosis, brucellosis, yersiniosis, tuberculosis, syphilis, Mycoplasma pneumoniae, Whipple disease
  • Other: toxoplasmosis, infective endocarditis, sepsis
• Malignancies: Multicentric Castleman disease, angioimmunoblastic lymphadenopathy, Hodgkin lymphoma, non-Hodgkin lymphoma, solid-organ maligancies, melanoma, angiosarcoma, myeloproliferative disorder, paraneoplastic syndrome
• Other autoimmune disorders: idiopathic inflammatory myopathy, seronegative rheumatoid arthritis, reactive arthritis, polyarteritis nodosa, familial Mediterranean fever, Mevalonate kinase deficiency, polymyositis, dermatomyositis, Sweet syndrome, sarcoidosis, Schnitzler syndrome, systemic lupus erythematosus
• DRESS
• Others: hemophagocytic lymphohistiocytosis, neutrophilic dermatosis, Kikuchi-Fujimoto disease

Diagnostic Criteria (Yamaguchi)

• Major criteria:
  • Fever ≥ 39 degrees C (102.2 degrees F) for ≥ 1 week
  • Arthralgia or arthritis for ≥ 2 weeks
  • Typical evanescent rash
  • Leukocytosis (white blood cells > 10,000/mm³) with ≥ 80% granulocytes
• Minor criteria:
  • Sore throat
  • Lymphadenopathy
  • Hepatomegaly or splenomegaly
  • Abnormal liver function tests
  • Absence of rheumatoid factor and antinuclear antibody
• Positive with ≥ 5 criteria including ≥ 2 major criteria

• Exclusion criteria include:
  • Infection
  • Malignancy, particularly malignant lymphoma
  • Other rheumatic disease, particularly systemic vasculitides