Prompt diagnosis and management of Epstein-Barr virus-associated post-transplant lymphoproliferative disorder and hemophagocytosis: A dreaded complication in a post-liver transplant child

Hemophagocytic lymphohistiocytosis after solid organ transplantation: A challenge for clinicians

Hemophagocytic lymphohistiocytosis (HLH) is a rare inflammatory disorder with a high mortality rate and a wide range of symptoms. Solid organ transplantation, which provides patients with a unique immunosuppressive state, is a less common predisposing factor for HLH. HLH after solid organ transplantation (HLH-SOT) is very rare and fatal. It is hard to diagnose and treat and extremely understudied. The use of immunosuppressants makes the situation of HLH-SOT more complex. This review summarizes the existing literature on HLH after solid organ transplantation and describes its triggers and symptoms, focusing on its diagnosis and treatment. We performed a literature search of case reports, case series, letters to the editor, and clinical quizzes describing patients with HLH after solid organ transplantation (HLH-SOT). We provide recommendations on the diagnosis protocol and treatment strategy based on the existing evidence.

Secondary hemophagocytic lymphohistiocytosis in children (Review)

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition characterized by hyperinflammation in an uncontrolled and ineffective immune response. Despite great improvement in diagnosis and treatment, it still represents a challenge in clinical management, with poor prognosis in the absence of an aggressive therapeutic approach. The present literature review focuses on secondary HLH at pediatric age, which represents a heterogeneous group in terms of etiology and therapeutic approach. It summarizes the most recent evidence on epidemiology, pathophysiology, diagnosis, treatment and prognosis, and provides a detailed description and comparison of the major subtypes of secondary HLH. Finally, it addresses the open questions with a focus on diagnosis and new treatment insights.

Ruxolitinib as Adjunctive Therapy for Hemophagocytic LymPhohistiocytosis after Liver Transplantation: A Case Report and Literature Review

Hemophagocytic lymphohistiocytosis (HLH) is a rare but potentially fatal hyperinflammatory disorder characterized by dysfunctional cytotoxic T and natural killer cells. Liver transplantation is a predisposing factor for HLH. High mortality rates were reported in 40 cases of HLH following liver transplantation in adults and children. Herein, we describe a case of adult HLH triggered by cytomegalovirus (CMV) infection shortly after liver transplantation. The patient was successfully treated with ruxolitinib combined with a modified HLH-2004 treatment strategy. Our case is the first to report the successful use of ruxolitinib with a modified HLH-2004 strategy to treat HLH in a solid organ transplantation recipient.

Graft-versus-host disease after liver transplantation is associated with bone marrow failure, hemophagocytosis, and DNMT3A mutations

Graft-versus-host disease after liver transplantation (LT-GVHD) is rare, frequently fatal, and associated with bone marrow failure (BMF), cytopenias, and hyperferritinemia. Given hyperferritinemia and cytopenias are present in hemophagocytic lymphohistiocytosis (HLH), and somatic mutations in hematopoietic cells are associated with hyperinflammatory responses (clonal hematopoiesis of indeterminate potential, CHIP), we identified the frequency of hemophagocytosis and CHIP mutations in LT-GVHD. We reviewed bone marrow aspirates and biopsies, quantified blood/marrow chimerism, and performed next-generation sequencing (NGS) with a targeted panel of genes relevant to myeloid malignancies, CHIP, and BMF. In all, 12 marrows were reviewed from 9 LT-GVHD patients. In all, 10 aspirates were evaluable for hemophagocytosis; 7 had adequate DNA for NGS. NGS was also performed on marrow from an LT cohort (n = 6) without GVHD. Nine of 10 aspirates in LT-GVHD patients showed increased hemophagocytosis. Five (71%) of 7 with LT-GVHD had DNMT3A mutations; only 1 of 6 in the non-GVHD LT cohort demonstrated DNMT3A mutation (p = .04). Only 1 LT-GVHD patient survived. BMF with HLH features was associated with poor hematopoietic recovery, and DNMT3A mutations were over-represented, in LT-GVHD patients. Identification of HLH features may guide prognosis and therapeutics. Further studies are needed to clarify the origin and impact of CHIP mutations on the hyperinflammatory state.

T Cell-Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis (HLH) Occurs in Non-Asians and Is Associated with a T Cell Activation State that Is Comparable to Primary HLH

Purpose

T cell-Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis (T cell-EBV-HLH) is prevalent in East Asia and has poor prognosis. Understanding of this disease is limited, and literature regarding prevalence in North America is scarce. Herein, we summarize our experience.

Methods

A retrospective analysis of T cell-EBV-HLH patients admitted to Children’s Healthcare of Atlanta (GA, USA) from 2010 to 2020 was conducted. Additional immune studies were completed in a subset of patients.

Results

We report 15 patients (10 months–19 years of age) diagnosed with T cell-EBV-HLH. Nine patients were Hispanic, and the majority did not have primary HLH (p-HLH) gene defects. Soluble interleukin-2 receptor levels in T cell-EBV-HLH were significantly higher than other forms of secondary-HLH but comparable to p-HLH, and it correlated with disease severity at presentation. Natural killer cell function was decreased in most patients despite a negative workup for p-HLH. Depending on disease severity, initial therapy included dexamethasone or dexamethasone and etoposide. Refractory patients were managed with blended regimens that included one or more of the following therapies: combination chemotherapy, alemtuzumab, emapalumab, and nivolumab. Rituximab did not appreciably decrease EBV viremia in most patients. Non-critically ill patients responded well to immunosuppressive therapy and are long-term survivors without undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Alemtuzumab resulted in inflammation flare in two of the three patients. Three patients underwent allogeneic HSCT, with disease relapse noted in one. At a median follow-up of 3 years, 10 of the 15 patients are alive.

Conclusion

T cell-EBV-HLH occurs in the USA among the non-Asian populations, especially in those who are Hispanic.

Fatal Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis with virus-infected T cells after pediatric multivisceral transplantation: A proof-of-concept case report

BACKGROUND

EBV-associated HLH driven by EBV-infected CD8⁺ T cells is a rare complication after pediatric solid organ transplantation. The etiology and disease spectrum of post-transplant EBV-HLH are poorly understood, and making a precise diagnosis and providing optimal treatment remain a challenge.

METHODS/CASE DESCRIPTION/RESULTS

We report a 2-year-old multivisceral transplant recipient who developed fever and cytopenia with a persistent high EBV-load state. Repeated tissue examinations and CT scans could not identify a localized mass, which is the key to the diagnosis of PTLD as per the WHO classification. Hence, EBV-HLH was diagnosed by clinical manifestations as well as characterization of EBV-infected cells, pathological examination on cell block of pleural effusion and clonality analysis. This EBV-HLH did not respond to intensive chemotherapy, resulted in the recipient's death, acting similarly to hematological malignancy.

CONCLUSIONS

Characterization of EBV-infected cells in peripheral blood should be considered when persistent high EBV loads develop with symptoms consistent with PTLD, but no evidence of localized mass, and the tissue diagnosis is unavailable after pediatric solid organ transplantation.

Autoimmune hemolytic anemia: An unusual presentation of hemophagocytic lymphohistiocytosis in a pediatric post-liver transplant patient

Hemophagocytic lymphohistiocytosis (HLH), a rare condition characterized by immune dysfunction with uncontrolled activation of macrophages and hypersecretion of cytokines, has only been reported in a small number of pediatric patients following solid organ transplant (SOT). The diagnosis of HLH after SOT is especially difficult, as several of the diagnostic criteria, including fever, splenomegaly, and cytopenias, are nonspecific and can be seen with other post-transplant complications. Autoimmune hemolytic anemia (AIHA) has also been reported after pediatric SOT and is thought to be related to immunosuppression, specifically tacrolimus. Although HLH and AIHA have been separately described following SOT, there have been no reports of them occurring together in post-liver transplant (LT) patients. We report the first case of autoimmune hemolysis as the presenting symptom of HLH in a pediatric post-LT patient.

Recent advances in the risk factors, diagnosis and management of Epstein-Barr virus post-transplant lymphoproliferative disease

Fifty years after the first reports of Epstein-Barr virus (EBV)-associated endemic Burkitt's lymphoma, EBV has emerged as the third most prevalent oncogenic virus worldwide. EBV infection is associated with various malignancies including Hodgkin and non-Hodgkin lymphoma, NK/T-cell lymphoma and nasopharyngeal carcinoma. Despite the highly specific immunologic control in the immunocompetent host, EBV can cause severe complications in the immunocompromised host (namely, post-transplant lymphoproliferative disease). This is particularly a problem in patients with delayed immune reconstitution post-hematopoietic stem cell transplant or solid organ transplant. Despite advances in diagnostic techniques and treatment algorithms allowing earlier identification and treatment of patients at highest risk, mortality rates remain as high as 90% if not treated early. The cornerstones of treatment include reduction in immunosuppression and in vivo B cell depletion with an anti-CD20 monoclonal antibody. However, these treatment modalities are not always feasible due to graft rejection, emergence of graft vs. host disease, and toxicity. Newer treatment modalities include the use of adoptive T cell therapy, which has shown promising results in various EBV-related malignancies. In this article we will review recent advances in risk factors, diagnosis and management of EBV-associated malignancies, particularly post-transplant lymphoproliferative disease. We will also discuss new and innovative treatment options including adoptive T cell therapy as well as management of special situations such as chronic active EBV and EBV-associated hemophagocytic lymphohistiocytosis.