Successful sequential liver and haematopoietic stem cell transplantation in a child with CD40 ligand deficiency and Cryptosporidium-induced liver cirrhosis.

Background. Hematopoietic stem cell transplantation (HSCT) is curative in patients with primary immunodeficiencies. However, pre-HSCTconditioning entails unacceptably high risks if the liver is compromised. The presence of a recurrent opportunistic infection affecting the biliary tree and determining liver cirrhosis with portal hypertension posed particular decisional difficulties in a 7-year-old child with X-linked CD40-ligand deficiency. We aim at adding to the scanty experience available on such rare cases, as successful management with sequential liver transplantation (LT) and HSCT has been reported in detail only in 1 young adult to date. Methods. A closely sequential strategy, with a surgical complication-free LT, followed by reduced-intensity conditioning, allowed HSCT to be performed only one month after LT, preventing Cryptosporidium parvum recolonization of the liver graft. Results. Combined sequential LT and HSCT resolved the cirrhotic evolution and corrected the immunodeficiency so that the infection responsible for the progressive sclerosing cholangitis did not recur. Conclusions. Hopefully, this report of the successful resolution of a potentially fatal combination of immunodeficiency and chronic opportunistic infection with end-stage organ damage in a child will encourage others to adapt a sequential transplant approach to this highly complex pathology. However, caution is to be exercised to carefully balance the risks intrinsic to transplant surgery and immunosuppression in primary immunodeficiencies.