Published online Jan 21, 2019. doi: 10.3748/wjg.v25.i3.367
Peer-review started: November 14, 2018
First decision: December 5, 2018
Revised: December 12, 2018
Accepted: December 21, 2018
Article in press: December 21, 2018
Published online: January 21, 2019
Biliary atresia patients have high chance of disease progression to liver fibrosis even after Kasai operation. Therefore, regular long-term monitoring is required to early diagnose liver cirrhosis and portal hypertension. The primary aim of this study was to evaluate the utility of magnetic resonance elastography (MRE) for hepatic and splenic stiffness assessments to evaluate portal hypertension in pediatric patients with biliary atresia after the Kasai operation.
Hepatic fibrosis has been found to correlate with liver MRE values in adult and children. However, there is little discussion about the relationship between spleen stiffness measurement by MRE and portal hypertension in children.
This study analyzed the role of spleen MRE values in biliary atresia patients after Kasai operation with portal hypertension.
We retrospectively reviewed abdominal MRE images in pediatric patients. Patients who had undergone Kasai operations for biliary atresia were selected for the Kasai group, and patients with normal livers and spleens were selected for the control group. Hepatic and splenic stiffness values were measured by MRE. Aspartate aminotransferase to platelet ratio index (APRI) from laboratory results and the normalized spleen size ratio were calculated. These parameters were compared between the Kasai group and the control group, and also among the Kasai group patients depending on the existence of portal hypertension or gastroesophageal varices.
The median spleen MRE value was 5.5 kPa in the control group and 8.6 kPa in the Kasai group. In the Kasai group, the APRI, spleen size ratio and spleen MRE values were higher in patients with portal hypertension and in patients with gastroesophageal varices, even though their liver MRE values were not different. The APRI, spleen size ratio and spleen MRE values also correlated with varices grades. The AUC in predicting gastroesophageal varices was 0.844 at a cut-off of 0.65 for the APRI, and 0.844 at a cut-off of 9.9 kPa for spleen MRE values.
Spleen MRE values were useful for evaluating portal hypertension and gastroesophageal varices in biliary atresia patients after Kasai operation. At a cut-off of 9.9 kPa, spleen MRE values predicted gastroesophageal varices as well as the APRI and spleen size ratio. However, liver MRE values did not differ in patients with and without portal hypertension or gastroesophageal varices. Spleen MRE values may help screen out high-risk patients early and administer adequate interventions during follow up.
For biliary atresia patients after Kasai operation, spleen MRE values can be used to evaluate portal hypertension and gastroesophageal varices without invasive monitoring. The results of this study, needs to be verified by a large sample size study with multiple institutions.