A case report of adult type 2 familial hemophagocytic lymphohistiocytosis

Abstract Familial hemophagocytic lymphohistiocytosis (FHL) is a fatal autosomal recessive disorder that often occurs in infants and young children, and rarely reported in adults. In this paper, we retrospectively reported an elderly woman with recurrent fever, this patient was diagnosed with familial hemophagocytic syndrome by perfecting relevant examinations after admission, improvement was observed after standard chemotherapy. In order to further determine the possible underlying genetic causes, we performed gene mutation analysis and found that there were compound heterozygous missense mutations c.133G > A (p.Gly45Arg) and c.147C > A (p.Asp49Glu) on the exon2 of PRF1 gene in this patient. According to the clinical manifestations and test results, the patient was further confirmed as late‐onset FHL‐2 type. Without a suitable donor, the patient did not perform hematopoietic stem cell transplantation. Therefore, the relevant genetic examination should be performed as early as possible in young patients with a family history of hemophagocytic lymphohistiocytosis, and it can provide a basis for etiological diagnosis and radical treatment by hematopoietic stem cell transplantation. It is essential to further study the molecular mechanism and clinical application value for late‐onset elderly FHL patients without appropriate donors.