Hemophagocytic lymphohistiocytosis in the context of hepatitis-associated severe aplastic anemia: A case report.

RATIONALE: Hemophagocytic lymphohistiocytosis (HLH) is a severe immune dysregulation syndrome. Hepatitis-associated severe aplastic anemia (SAA) is a specific subtype of acquired aplastic anemia characterized by concomitant hepatitis, leading to a challenging diagnosis and poor prognosis. Here, we present a rare case of HLH in the context of hepatitis-associated SAA, emphasizing the need for early recognition and individualized management.

PATIENT CONCERNS: The patient, a 19-year-old male, presented with recurrent fever, jaundice, and cytopenias, indicative of hepatitis.

DIAGNOSES: Bone marrow aspiration and biopsy suggested SAA, while peripheral blood next-generation sequencing detected Candida tropicalis infection on 2 separate occasions. Despite combination antifungal therapy with amphotericin B and posaconazole, the bilirubin level continued to rise. Additional tests revealed an elevated soluble CD25 level of 3659 U/mL, decreased natural killer cell activity of 1.8%, and a serum ferritin level > 2000 μg/L. The final diagnosis was HLH.

INTERVENTIONS: Dexamethasone and ruxolitinib were administered to control the fever. Subsequently, the patient underwent HLA-matched allogeneic bone marrow and peripheral blood hematopoietic stem cell transplantation for SAA.

OUTCOMES: The patient's symptoms, including fever and fatigue, resolved.

LESSONS: This case highlights that HLH should be considered in SAA patients with unexplained fever, poor response to anti-infectives, and elevated bilirubin. A treatment strategy addressing both bone marrow failure and hyperinflammation is essential. In this patient, allogeneic hematopoietic stem cell transplantation served as a successful curative intervention by targeting the shared pathophysiology of HLH and SAA. However, given the inherent limitations of a single case, the generalizability of our findings and the efficacy of allogeneic hematopoietic stem cell transplantation require validation through larger, controlled studies.