Spleen elastography in patients with Systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune inflammatory connective tissue disease. It is characterized by varying degrees of fibrosis of the skin and internal organs. Tissue fibrosis is the final phase of a complex biological process of immune activation and vascular damage. The spleen is one of the organs thought to be involved in a systemic fibrosing process. Yet, there is a lack of research that provides evidence about splenic involvement in patients with SSc through objective instrumental techniques. Ultrasound elastography is a modern method which detects changes in the stiffness and elasticity of different organs. To assess the elasticity and stiffness of the spleen in healthy subjects and patients with SSc, the study included 34 patients with SSc and 35 healthy volunteers. Point SWE spleen elastography was performed on all participants in the two study groups through an Esaote MyLab 9 eXP with a C1-8 iQ appleprobe transducer. The mean age in the SSc patient group was 47.35 ± 11.48 years vs. 46.20 ± 14.55 years in the healthy controls, with no significant age difference, p = 0.717. The mean Body Mass Index (BMI) in the SSc patient group was 22.42 ± 2.12 kg/m² vs. 24.23 ± 4.29 kg/m² in the healthy control group with no significant difference, p = 0.410. Among the SSc patients, 18(53%) were with dcSSc and 16 (47%) with lcSSc. The mean disease duration was 59 ± 28 months, ranging between 18 and 118 months. Spleen stiffness median was significantly higher in the SSc patient group (3.19 m/s) in comparison with the healthy controls (2.40 m/s), p < 0.001. Spleen size was normally distributed and did not differ significantly between the SSc patients (105.84 ± 7.87 mm) and the healthy controls (104.16 ± 8.99 mm), p = 0.410. A significantly higher mean of spleen stiffness was observed in the dcSSc patients (3.38 ± 0.20 m/s) in comparison with the lcSSc group (2.81 ± 0.38 m/s), p < 0.001. Spleen size did not show a significant association with the type of SSc. Spleen size in the dcSSc subgroup had a mean value of 103.45 ± 5.56 mm vs. 108.51 ± 9.30 in the lcSSc subgroup, p = 0.071. pSWE is an objective, reliable, and easy-to-implement method for detecting early fibrous changes in the spleen in patients with SSc. A good approach in patients with SSc could be the search for similar processes in other internal organs, such as the liver and thyroid gland.