Dilatation of lymphatic vessels increases liver stiffness on transient elastography irrespective of fibrosis

Aim Liver stiffness measured using transient elastography (TE) is affected by tissue viscosity. The role of intrahepatic lymphatic fluid in liver stiffness is unclear. The present study aimed to investigate the effects of lymphatic vessel dilatation on liver stiffness. Methods Patients with chronic liver disease (n = 116) were enrolled from June 2018 to March 2020. All specimens were acquired by laparoscopic liver biopsy. Biopsy samples were stained with D2-40 for lymphatic vessel quantification based on a five-point scale for each specimen. Independent associations of liver stiffness measured by TE, strain elasticity (liver fibrosis index), and controlled attenuation parameter with fibrosis, lymphatic vessels, alanine aminotransferase, bilirubin, and steatosis were evaluated. Results Fibrosis, splenic stiffness measurement, and splenic volume were significantly correlated with the area of lymphatic vessels. Fibrosis, lymphatic vessels, and alanine aminotransferase were independent factors significantly associated with liver stiffness measurement (LSM; standardized coefficient [beta] = 0.375, P beta = 0.342, P beta = 0.359, P < 0.001, respectively). Fibrosis was the only independent factor significantly associated with liver fibrosis index (beta = 0.360, P < 0.001), whereas the fat deposit area was the only independent factor significantly associated with controlled attenuation parameter (beta = 0.455, P < 0.001). The areas under the receiver operating characteristic curves for diagnosing controlled ascites based on LSM, liver fibrosis index, splenic stiffness measurement, collagen proportionate area, and area of lymphatic vessels were 0.94, 0.66, 0.76, 0.64, and 0.79, respectively. Conclusions Lymphatic vessel dilatation can affect liver stiffness measured using TE. Liver stiffness measurement is a predictive factor for ascites.