Clinical features of adult-onset Still disease

Mimura, 2018

Diagnosis of adult-onset Still disease requires both a clinical presentation (consistent with adult-onset Still disease) and exclusion of conditions with similar presentations (eg infection, malignancy, particularly lymphoma). An extensive classification system is available but has not been validated for clinical practiceGiacomelli, 2018.

The cardinal clinical features of adult-onset Still disease are:

  • arthralgias and polyarthritis
  • high quotidian fever (spiking once or twice daily)
  • macular or maculopapular, evanescent, salmon-pink rash
  • raised inflammatory markers and hyperferritinaemia.

For more details on these cardinal clinical features and a broad spectrum of other symptoms, see Clinical features and investigation findings in adult-onset Still disease.

There are many potential differential diagnoses for adult-onset Still disease and the diagnosis is often significantly delayed (eg 6 to 12 months) while more likely diagnoses (eg abscess) are investigated. Consider adult-onset Still disease in people with recurrent fevers, particularly if they do not follow a typical course or respond to treatment as expected.

Note: Consider adult-onset Still disease in people with recurrent fevers, particularly if they do not follow a typical course or respond to treatment as expected.
Figure 1. Clinical features and investigation findings in adult-onset Still disease. Giacomelli, 2018Tomaras, 2021

Cardinal clinical features of adult-onset Still disease include:

  • arthralgias, polyarthritis of small joints
  • quotidian, spiking fever; typically 39°C or higher
  • evanescent, salmon-pink maculopapular rash
  • hyperferritinaemia, leucocytosis and raised inflammatory markers (see Investigation findings)

Other frequent clinical features of adult-onset Still disease include:

  • odynophagia, pharyngitis
  • persistent erythematous rash
  • myalgia, myositis
  • lymphadenopathy, splenomegaly
  • hepatomegaly, hepatitis
  • pericarditis, myocarditis, pleuritis, interstitial lung disease.

Life-threatening complications of adult-onset Still disease include:

  • cardiac tamponade, myocarditis, acute respiratory distress syndrome
  • pulmonary arterial hypertension
  • fulminant hepatitis
  • macrophage activation syndrome (also known as haemophagocytic lymphohistiocytosis)
  • disseminated intravascular coagulation
  • thrombotic microangiopathy.

Common investigation findings include:

  • raised inflammatory markers—ESR, serum CRP concentration and fibrinogen concentration
  • very high serum ferritin concentration—at least 5 times the upper limit of the normal range but often much higher (eg 5000 microgram/L)
  • marked neutrophil leucocytosis [NB1]—WCC more than 11 × 109/L and neutrophils more than 80%
  • abnormal liver aminotransferases.
Note:

ESR = erythrocyte sedimentation rate; CRP = C-reactive protein; WCC = white cell count

NB1: If leucopenia rather than leucocytosis is present, it may represent disease complications (such as macrophage activation syndrome or thrombotic microangiopathy).