Multi-center study validates systemic score in identifying high-risk patients with Still's disease

European Alliance of Associations for Rheumatology (EULAR)Jun 12 2024

A multi-center, observational, prospective study was designed to evaluate the clinical usefulness of the systemic score in predicting life-threatening evolution – defined as the development of macrophage activation syndrome (MAS) and/or mortality. The intention was also to derive a more aggressive clinical patient subset. To achieve this, Ruscitti and colleagues collected data from 597 patients taking part in the GIRRCS (Gruppo Italiano Di Ricerca in Reumatologia Clinica e Sperimentale) AOSD-study group and in the AIDA (AutoInflammatory Disease Alliance) Still's disease registry –. First developed in the 1990s, the prognostic value of the systemic score has previously been tested in a small number of cases. The new work was presented in a session on the management of Still's disease across the life-span at the 2024 congress of EULAR – The European Alliance of Rheumatology Associations.

Each patient was assessed for the systemic score, which assigns 1 point to each of 12 manifestations: fever, typical rash, pleuritis, pneumonia, pericarditis, hepatomegaly or abnormal liver function tests, splenomegaly, lymphadenopathy, leucocytosis > 15,000/mm³, sore throat, myalgia, and abdominal pain.

When looking at manifestations, 100% of patients included had fever, 87.9% had joint involvement, and 66.1% had skin rash. Liver involvement was recognized in 43.5%, MAS in 13.1%, and lung disease in 6.9%. There was a mortality rate of 3.4% attributed to Still's disease.

A result of at least 7 on the systemic score proved to be a significant predictor of life-threatening evolution. To further explore this, a risk-profile assessment was performed on the clinical variables used to calculate the systemic score, and an age- and sex-adjusted multivariate logistic regression model built. This showed that liver involvement and lung disease independently predicted life-threatening evolution. The clinical characteristics of this subset of patients was then derived, revealing that those with liver involvement were significantly characterized by lymph-adenomegaly, splenomegaly, pericarditis, and pleuritis – and were also burdened by lung disease.

In the patients with lung disease, significant characteristics were sore throat, lymph-adenomegaly, splenomegaly, and liver involvement. Furthermore, those with lung disease showed a higher frequency of pericarditis, pleuritis, and abdominal pain. This subset was also burdened with a higher mortality rate.

The results suggest that the systemic score could be used as a prognostic tool in clinical practice. Additionally, liver involvement and lung disease are clinically relevant findings, and should be highlighted as key multi-organ manifestations of Still's disease, and as major predictors of life-threatening evolution.