Soluble Triggering Receptors on Myeloid Cells‐1 Could Be a Potential Biomarker for Disease Activity in Familial Mediterranean Fever

OBJECTIVES: Familial Mediterranean Fever (FMF) is an autoinflammatory disease. We aimed to investigate serum soluble Triggering Receptor Expressed on Myeloid Cells-1 and 2 (sTREM-1 and sTREM-2) levels in patients with FMF during both attack and attack-free periods and their relationship with disease activity. METHODS: Fifty-seven FMF patients, 27 in the attack and 30 in the attack-free period, along with 30 age- and sex-matched healthy controls, were enrolled in the study. Demographic and clinical data were obtained from hospital records, and the disease severity scores (DSS) were calculated. Serum levels of sTREM-1, sTREM-2, TNF-α, and IL-1β were assayed by ELISA. CRP levels were measured by the nephelometric method. Receiver operating characteristic (ROC) analysis was performed for sTREM-1 levels to detect attacks in patients with FMF. RESULTS: sTREM-1 levels were significantly higher in the attack group than in the attack-free and control groups (p < 0.001). IL-1β levels were elevated in FMF patients (p = 0.003), and CRP levels differed significantly among the groups (p < 0.001). No significant differences in sTREM-2 or TNF-α were observed. In the FMF-attack group, sTREM-1 positively correlated with TNF-α (r = 0.526, p = 0.005), IL-1β (r = 0.475, p = 0.014), CRP, and fibrinogen (p < 0.001). The DSS was significantly correlated with sTREM-1 and CRP levels in FMF patients (respectively, r = 0.270, p = 0.042; r = 0.292, p = 0.027). The area under the curve (AUC) was 0.807 (95% CI, 0.695-0.92, p < 0.001), with an optimal sTREM-1 cutoff of 232 pg/mL to detect attacks. CONCLUSION: sTREM-1 may play a critical role in the inflammatory response in FMF disease and could serve as a potential marker for assessing disease activity.