CXCL-9, CXCL-10, CXCL-10, IFN-γ elevated in adult-onset Still’s disease
Increased serum levels of C-X-C motif chemokine (CXCL)-11, CXCL-9, CXCL-10 and interferon (IFN)-γ are associated with clinical manifestations of adult-onset Still’s disease (AOSD), reports a new study.
The study included 39 patients with untreated AOSD, 30 with rheumatoid arthritis (RA) and 28 healthy controls. Those with autoimmune, neoplastic and infectious disorders were excluded. Baseline demographic information, clinical characteristics, AOSD activity and laboratory findings were recorded.
Enzyme-linked immunosorbent assays (ELISA) were used to measure serum levels of CXCL-11, CXCL-9, CXCL-10, IFN-β, IFN-α and IFN-γ. Skin biopsies from 34 AOSD patients were subjected to histopathological analysis to determine disease activity.
Among the three groups, there were no significant differences in gender or age. The most common symptoms of AOSD were high spiking fevers (94.9 percent) followed by skin rashes (87.2 percent), arthritis (53.8 percent), sore throat (56.4 percent) and splenomegaly (20.5 percent). At baseline, all AOSD patients had high levels of disease activity.
AOSD patients had significantly higher levels of IFN-γ (50.5±34.4 pg/mL) compared with RA patients (27.7±21.4 pg/mL; p=0.001) and healthy controls (23.7±11.1 pg/mL; p<0.001). Similarly, CXCL-9 (595.6±790.8 pg/mL) and CXCL-10 (229.5±188.1 pg/mL) levels were significantly higher in AOSD patients than in RA patients (p<0.001 for both) and healthy controls (p<0.001 for both).
Further analysis showed that levels of CXCL-9 (p=0.004), CXCL-10 (p=0.003) and CXCL-11 (p=0.017) were significantly greater in AOSD patients with reactive haemophagocytic syndrome (RHS) than those without. IFN-γ levels were not significantly different between the two groups.
Finally, in follow-up samples collected 8.1±6 months after initial collections, mean levels of CXCL-9, CXCL-10 and CXCL-11 decreased significantly compared with initial samples. The level of IFN-γ did not change significantly.