Elevated expression of TLR2 and its correlation with disease activity and clinical manifestations in adult-onset Still's disease.

This study investigated the role of Toll-like receptor 1 (TLR1), TLR2, TLR4, TLR7, and TLR9 in patients with adult-onset Still's disease (AOSD). This study included 20 patients with AOSD and 15 healthy controls (HCs). TLR expression in the peripheral blood was quantified using flow cytometry; TLR expression pattern, in the skin lesions and lymph nodes (LNs) of patients with AOSD, was evaluated immunohistochemically. Significantly higher mean intensities of cells presenting TLR2 and TLR7 from whole blood were observed in patients with AOSD than in HCs. TLR2 expression in whole cells correlated with systemic scores, levels of lactate dehydrogenase and ferritin and serum levels of interleukin-1ß (IL-1ß), IL-6, and IL-18. The percentage of TLR2-positive inflammatory cells was higher in skin biopsy samples from patients with AOSD than those in HCs. TLR9-expressing positive inflammatory cell counts were higher in skin lesions from patients with AOSD than those in the HC, eczema, and psoriasis groups. The expression levels of TLR1, TLR4, TLR7, and TLR9 were higher in LNs of patients with AOSD than in those with T cell lymphoma and reactive lymphadenopathy. Circulating TLR2- and TLR7-positive cells may contribute to the pathogenesis of AOSD. Furthermore, immunohistochemical staining for TLRs in skin lesions and LNs may aid in differentiating AOSD from similar conditions.

Flare of adult-onset Still's disease following mRNA COVID-19 vaccination: a case report and review of literature.

The upheaval caused by the coronavirus disease 2019 (COVID-19) pandemic has allowed to large population to use new vaccines urgently. Although vaccine development programs and available epidemiological data reassure us, there are concerns about specific risks associated with vaccinations in patients with autoimmune-autoinflammatory diseases. These patients have the potential to decrease humoral and cellular immune responses caused by biologic agents and develop an acute flare of underlying disease following vaccination. We herein present a rare case of a 49-year-old female with a flare of adult-onset Still's disease (AOSD) after the first dose of BNT162b2 mRNA COVID-19 vaccination. She had been diagnosed with AOSD 7 years earlier and had achieved remission with tocilizumab. This patient came to the emergency room with fever and nausea that occurred 4 days after the first vaccination. Based on laboratory results and clinical manifestations, we suspected AOSD flare and was treated with steroid pulse therapy. In this report, we also discuss possible mechanisms linking vaccination with a flare of AOSD. Considering the close time relationship between COVID-19 vaccinations and a flare of AOSD, physicians should be aware of adverse events from this new vaccination and evaluate the benefits and risks of vaccination for each patient. KEY POINTS: • COVID-19 vaccination may cause an AOSD flare in patients who are in remission with tocilizumab.