The 19th symposium of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism (ISHEN) took place virtually (organized from Padova, in Italy) on 6–8 October 2021. The first day of the congress was dedicated to the state of the art of the field, the second to novel findings mostly presented by young researchers, and the third to a forecast for the future of hepatic encephalopathy (HE) in terms of diagnosis, prognosis, and treatment. There were 40 between invited lectures and selected oral presentations, which were followed online by up to 368 registered viewers. A total of 1455 views were recorded after the meeting for the lectures that remained online until December 2021. This special issue of Metabolic Brain Disease encompasses the proceedings of the meeting in the form of a selection of papers covering HE pathophysiology, facilitating factors, diagnosis by means of novel and remote technology, prevention and treatment, also of highly recurrent and persistent HE, which is particularly difficult to manage.

We hope you will enjoy reading it while we wait to meet in person in Bad Zwischenahn, in Germany, for the 20th ISHEN Symposium on September 27–29, 2023.

Sara Montagnese, Past ISHEN President

Mette Lauridsen, ISHEN Secretary