Derivation of Splenic Stiffness in Subjects with Normal Liver Stiffness and No Vascular Liver Disease Using Transient Elastography with a Spleen-Dedicated Module: A Large Cross Sectional Study.

BACKGROUND

Liver and splenic stiffness measurements (LSM and SSM) are useful to predict varices and clinical decompensation in cirrhosis. SSM values are highly variable and overlapping and no guidelines exists on what constitutes normal SSM, that might limit interpretation of results.

METHODS

Consecutive subjects with LSM < 6 kPa and reliable SSM (FibroScan630 Expert device with spleen-dedicated module) and no vascular liver disease were analysed for significant correlations of SSM values with age, sex, BMI, portal and splenic vein diameter, splenic diameter, liver fat and diabetes. Based on timeline of SSM, subjects were randomly assigned in 70:30 ratio into derivation [n = 502] and validation subset [n = 214].

RESULTS

Of 7200 subjects with simultaneous reliable LSM and SSM, 715 fulfilled the selection criteria (mean age: 43.8 ± 12.8 years, 67.2% male, mean BMI-26.4 ± 4.5 kg/m). The mean SSM was 22.6 ± 5.8 kPa (c10-c90 percentile range: 15.2-31.3 kPa) and followed the normal distribution curve. In the derivation subset, mean SSM for males was higher than female (23.06 ± 6.2 vs. 21.78 ± 5.93 kPa; p = 0.028). SSM value correlated with LSM (r = 0.454, p = 0.001). Mean SSM in subjects with LSM 3-4, 4.1-5 and 5.1-6 kPa were 21.7 ± 5.8, 22.27 ± 5.67 and 23.76 ± 5.88 kPa (p value = 0.001). There was no difference in SSM based on age, BMI, diabetes and liver fat on ultrasound. Above results hold true for subjects in validation subset.

CONCLUSION

SSM range in subjects with normal LSM and no vascular liver disease using spleen-dedicated module varies from 15.2 to 31.3 kPa, values being higher in male and not affected by Age, BMI, spleen size, liver fat and diabetes. Our results may serve as reference point in evaluation of SSM in compensated advanced liver disease patients.