Spleen stiffness can non-invasively assess resolution of portal hypertension after liver transplantation

Background & aims: Spleen stiffness can be measured by transient elastography. Recent studies have shown that spleen stiffness correlates with hepatic venous pressure gradient and can predict oesophageal varices. Elevated spleen stiffness in cirrhosis has been attributed to splenic tissue hyperplasia and fibrosis, portal hypertension and its consequent hyperdynamic circulation. The aim of this study was to investigate changes to spleen stiffness after orthotopic liver transplantation (OLT) when portal hypertension resolves.

Methods: Twenty-one patients awaiting OLT were studied prospectively, while 11 post-transplant patients were recruited as controls. Spleen and liver stiffness were measured with Fibroscan before and at 2-8 weeks after OLT. Criteria applied for spleen stiffness measurement were similar to liver stiffness (≥10 measurements; ≥60% success rate; interquartile range, IQR <30% of median).

Results: Spleen stiffness was significantly higher before OLT compared to post-transplant patients [75.0 (63.9-75.0) kPa vs. 28.4 (22.0-37.5) kPa; P < 0.0001]. For patients awaiting OLT, 90% (19/21) had oesophageal varices (endoscopically or radiologically). In patients who underwent liver transplantation, spleen stiffness decreased significantly from a median of 75.0 (62.0-75.0) kPa before OLT, to 41.9 (27.0-47.4) kPa at 2 weeks after transplant and 32.9 (29.1-38.0) kPa in the subsequent 4-8 weeks after OLT (P < 0.0001). As expected, liver stiffness measurements reduced from 39.3 (24.9-75.0) kPa to 8.6 (6.8-11.8) kPa in patients receiving OLT (P = 0.0004).

Conclusions: Spleen stiffness can non-invasively assess changes in portal pressure after liver transplantation and decreases significantly when portal hypertension resolves.