Reciprocal bone marrow transplantation between brother and sister

A child with AML underwent allogeneic BMT from an HLA-identical sister donor. Prompt and stable trilineage engraftment occurred and after few months he returned to a normal life. Eight years later a primary NHL of bone developed in his sister. A partial remission was obtained by means of standard NHL treatment, but 3 months later rapid disease progression occurred with complete bone marrow invasion (ALL-L3). She was treated with a leukemia relapse protocol, obtaining a second partial remission. Unpurged bone marrow harvested from the brother, transplanted for AML 8 years earlier, was infused after conditioning with TBI and thiothepa. No GVHD prophylaxis was given. Neutrophil engraftment occurred by 14 days and platelet engraftment by 20 days after BMT. No acute GVHD was observed, but unexpectedly she developed skin and liver GVHD-like symptoms 80 days after BMT. Since the liver biopsy was suggestive of liver GVHD and in the absence of any other evidence as a possible cause of the hepatic damage, the patient started mycophenolate. Two months later serum hepatitis B markers were detectable.