Combined liver and hematopoietic stem cell transplantation in patients with X-linked hyper-IgM syndrome

The diagnosis of XHIGM should not be an a priori reason to exclude patients with XHIGM from LT, as long as HSCT is included in the treatment strategy. Our recommendation for these patients is to perform HSCT before LT. Our case series demonstrates the fundamental importance of immune reconstitution to control infection and allow a successful LT, as shown by the 100% rate of Cryptosporidium species recurrence in patients who received only LT or who experienced HSC graft failure. In case of fulminant liver failure and urgent LT, we recommend planning an HSCT as soon as possible after the LT, preferably after healing of the surgical wounds. As for conditioning and support therapy, we suggest a preference for reduced-intensity regimens, to avoid cyclophosphamide if possible, and to implement fluid restriction and ursodeoxycholic acid therapy during conditioning to reduce the risk of veno-occlusive disease.