Shear-Wave Elastography–Based Assessment of Liver, Spleen, and Thyroid Stiffness in Children with Familial Mediterranean Fever in Remission: A Prospective Case–Control Study

OBJECTIVES: To determine whether shear-wave elastography (SWE) can detect subclinical parenchymal changes related to chronic inflammation and AA amyloid risk by measuring liver, spleen, and thyroid stiffness in children with Familial Mediterranean Fever (FMF) in remission compared with healthy controls. METHODS: In this prospective case-control study, 43 children with FMF and 50 age- and sex-matched healthy controls underwent SWE of the liver, spleen, and thyroid using a standardized protocol. All FMF patients were evaluated during clinical remission. Clinical characteristics and laboratory parameters, including inflammatory markers, were recorded. Measurements were performed by two blinded radiologists. For the liver and spleen, five technically valid ROIs were obtained from each organ; for the thyroid gland, five ROIs were obtained from each lobe. The arithmetic mean of technically valid ROI measurements was used as the final stiffness value for each organ. RESULTS: AST, ALT, ESR, and CRP levels were higher in the FMF group (all p < 0.001). However, liver, spleen, and thyroid stiffness values did not differ between groups (all p > 0.05). Thyroid stiffness showed a weak, non-significant association with ESR (Spearman's rho = 0.376, p = 0.013). CONCLUSIONS: SWE-derived stiffness values were similar between children with FMF in remission and controls, suggesting limited sensitivity for detecting subclinical organ involvement. ADVANCES IN KNOWLEDGE: This study demonstrates that SWE-derived organ stiffness remains unchanged in children with FMF in remission despite biochemical evidence of low-grade inflammation, highlighting the need for further studies across different disease states and longitudinal settings.