Still's disease belongs to the systemic auto-inflammatory diseases, which usually manifest themselves in early childhood (as systemic juvenile idiopathic arthritis (SJIA)) or in adulthood (Still's syndrome). During the course of the disease, the innate immune system is activated. To date, little is known about which trigger(s) in AOSD leads to this activation.
The onset of the disease is often between the ages of 15 and 40. However, two age peaks between 15 and 25 years and between 36 and 46 years are also observed for the onset of the disease. Less than 10% of patients are older than 50 years at the beginning of the disease.
Both, Still's disease and SJIA, are associated with a high activity of interleukin-1 (inflammatory messenger).
Figures around the disease
Still's disease in adults occurs worldwide. It is estimated that less than 1 person per 100,000 inhabitants suffers from AOSD. Women and men are equally affected, but women seem to develop joint problems more often than men.
Still's disease is always diagnosed in the context of an exclusion diagnosis. Infections, malignancies and other rheumatological diseases (mainly systolic vasculitis) must first be excluded.
The standard Yamaguchi Classification criteria of 1992 (Yamaguchi M et al., J Rheumatol 1992; 19:424-430) are used: Five or more criteria are required, whereby at least two main criteria must be fulfilled.
In principle, the choice of therapy is based on a consensus between the rheumatologist and the patient. A German guideline recommendation does not currently exist for Still's disease.
With fever > 39°C, ≥ 1 week and exclusion of malignancies and infections, autoinflammatory diseases should also be considered and a rheumatologist should be consulted. Especially, if ferritin is also massively increased (> 3-5 times the normal value).