Salvage treatment of ruxolitinib for refractory adenovirus-associated hemophagocytic syndrome post-haploidentical allogeneic stem cell transplantation: a case report.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a rare complication following hematopoietic stem cell transplantation (HSCT). Currently, there is a lack of consensus recommendations for the treatment of post-transplant HLH. This case report emphasizes the successful utilization of ruxolitinib as a salvage therapy for HLH post-HSCT. The aim is to provide valuable insights into the optimal management of this rare and complex complication. Case Description: We present a case study of an 11-year-old male patient diagnosed with severe aplastic anemia who received a haploidentical HSCT. On the 86th day post-transplantation, the patient developed recurrent fever, hepatomegaly, hypertriglyceridemia, severe pancytopenia, and elevated levels of inflammatory factors and ferritin. Hemophagocytosis was observed in the bone marrow, and subsequent DNA next-generation sequencing identified adenovirus type C infection, leading to a diagnosis of adenovirus-associated HLH. After unsuccessful treatment attempts with cidofovir, dexamethasone, immunoglobulin, plasmapheresis, and etoposide, ruxolitinib was administered. Remarkably, the patient's clinical symptoms rapidly improved, and his test results gradually normalized with ruxolitinib therapy. The adenovirus viral load became undetectable by the 180th day. With continuous remission, ruxolitinib was discontinued on the 137th day post-transplantation, and a 15-month follow-up examination showed no relapse. Conclusions: We present a case of adenovirus-related secondary HLH (sHLH) post-HSCT, which was effectively treated with ruxolitinib. Our case highlights the potential of ruxolitinib as a therapeutic option for patients with viral infections and sHLH. Nonetheless, the safety and efficacy of this innovative treatment should be evaluated in forthcoming large-scale clinical trials.