European Reference Networks (ERNs https://health.ec.europa.eu/european-reference-networks_it) are virtual networks involving healthcare centers across Europe, with the task of facilitating discussion and diagnosis of rare or complex diseases requiring highly specialized treatment. The first ERNs were launched in March 2017, involving more than 900 highly-specialized healthcare units from over 300 hospitals in 26 EU countries.

Selecting the centers that are part of the ERNs takes into account several characteristics of the candidate hospitals: patient management and care, organization and management of the center, research activities, skills, information systems, and a set of criteria relating to the specific diseases treated. ISMETT is part of the European Reference Network on Transplantation in Children (incl. HSCT, heart, kidney, liver, intestinal, length and multiorgan).