Abstract
We report the case of a 32-day-old boy admitted to our hospital for hemophagocytic lymphohistiocytosis (HLH). When he was 27 days old, he had a fever, followed by pancytopenia, liver failure, and high levels of ferritin. When he was transported to our hospital, he required intensive care because of cardiorespiratory failure. Since a genetic test revealed PRF1 mutation, he was diagnosed as having familial hemophagocytic lymphohistiocytosis (FHL) type2. He was found to be a compound heterozygote for c.1090_1091delCT and c.658G>A mutations. The pathogenesis of the c.658G>A mutation has not yet been fully characterized. However, a homozygote for c.658G>A mutations was reported to express no perforin and develop FHL2. The combination of this compound heterozygote for a c.1090_1091delCT mutation and a c.658G>A mutation has not yet been reported. This is the first report of a case of FHL2 with a c.658G>A mutation in Japan. We carried out cord blood transplantation after non-myeloablative conditioning. He died on the day after his first transplant because of severe complications and high disease activity. FHL is a very rare disease. Therefore, pathogenic mutations associated with this disease should be widely studied by accumulating reports of novel gene mutations.
