Urgent haploidentical haematopoietic cell transplantation may be considered in cases of severe aplastic anaemia (SAA) without a human leukocyte antigen-matched donor and suffering from severe infection. However, deciding on allogeneic transplantation in the setting of active systemic infection is challenging due to poor outcomes. This report presents a case of disseminated Magnusiomyces capitatus infection in a 5-year-old male who underwent immunosuppressive therapy for hepatitis-associated SAA. To address the critical situation, granulocyte transfusion was promptly administered from the patient's mother, followed by unmanipulated haploidentical peripheral blood stem cell transplantation from the patient's father with posttransplant cyclophosphamide, ultimately resulting in successful rescue.

HLA-haploidentical stem cell transplantation (haplo-SCT) using post-transplant high-dose cyclophosphamide (PT-CY) is an alternative choice when a suitable donors is unavailable. However, PT-CY is difficult in patients with Fanconi anemia (FA) due to their high vulnerability to alkylating agents. For FA, we prefer haplo-SCT by T-cell receptor αβT-cell and B-cell depletion (αβT/B-depleted haplo-SCT), which can reduce the risks of PT-CY-related complications and graft-versus-host disease (GVHD). An 11-year-old boy with diagnosed FA ( FANCG mutation) and bone marrow failure was to receive αβT/B-depleted haplo-SCT from his father (HLA 4/8 allele matched) due to absence of an HLA-matched donors. αβT/B-depleted peripheral blood stem cells (CD34 + cell count, 1.17 × 10 7 /kg; αβ + T-cell count, 1.3 × 10 5 /kg) were infused following conditioning consisting of fludarabine (150 mg/m 2 ), cyclophosphamide (40 mg/kg), anti-thymocyte globulin (5 mg/kg), rituximab (375 mg/m 2 ), and thoraco-abdominal irradiation (3 Gy). Tacrolimus was used for GVHD prophylaxis until day + 30. Neutrophil engraftment was achieved on day + 9, and complete chimerism was confirmed on days + 28 and + 96. At 12-month post-SCT, the patient was well without GVHD or any other complications. αβT/B-depleted haplo-SCT is a good choice not only for patients unsuitable for PT-CY, but also for all pediatric recipients to reduce SCT-related complications.

When Epstein-Barr virus (EBV) infection is suspected, identification of infected cells is important to understand the pathogenesis, determinine the treatment strategy, and predict the prognosis. We used the PrimeFlow™ RNA Assay Kit with a probe to detect EBV-encoded small RNAs (EBERs) and multiple surface markers, to identify EBV-infected cells by flow cytometry. We analyzed a total of 24 patients [11 with chronic active EBV disease (CAEBV), 3 with hydroa vacciniforme lymphoproliferative disorder, 2 with X-linked lymphoproliferative disease type 1 (XLP1), 2 with EBV-associated hemophagocytic lymphohistiocytosis, and 6 with posttransplant lymphoproliferative disorder (PTLD)]. We compared infected cells using conventional quantitative PCR methods and confirmed that infected cell types were identical in most patients. Patients with CAEBV had widespread infection in T and NK cells, but a small amount of B cells were also infected, and infection in patients with XLP1 and PTLD was not limited to B cells. EBV-associated diseases are believed to be complex pathologies caused by EBV infecting a variety of cells other than B cells. We also demonstrated that infected cells were positive for HLA-DR in patients with CAEBV. EBER flow FISH can identify EBV-infected cells with high sensitivity and is useful for elucidating the pathogenesis.

Topic: 22. Stem cell transplantation - Clinical Background: After allogeneic hematopoietic stem cell transplantation (Allo-HSCT), EBV often causes reactivation. Sometimes, EBV reactivation progresses to lymphoproliferative disorder (LPD). Post-transplant risk factors for EBV reactivation include acute or chronic GVHD requiring intensive immunosuppressants (IMMs), high viral load, and mesenchymal stem cell therapy (Haematologica.2016;101:803). Evaluation of EBV reactivation is especially important. A definitive diagnosis of LPD can be made by biopsy, which is not easy depending on the patient’s general condition. Monitoring DNA in the peripheral blood is particularly useful in predicting the development of LPD. (Rev Med Virol.2020;30:e2108). Aims: Our aim was to analyze the clinical features and prognostic impact of EBV viral load status in Allo-HSCT recipients. Methods: A total of 121 consecutive patients who underwent Allo-HSCT between December 2011 and February 2022 at Japanese Red Cross Narita Hospital, Narita, Chiba, Japan, were included. And, we performed EBV DNA quantification after transplantation. EBV DNA quantification was performed in whole blood (WB). For EBV viral load analysis, cases in which EBV viral load was measured over time after transplantation were included in the study. This study grouped patients in which EBV DNA quantification reached >1000 copies/mL in WB during follow-up (N=50) and those who did not (N=71). And for the group that reached 1000 copies/mL or more, we analyzed the relationship between the rate of decline of IMMs and prognosis. Results: The median age of 122 patients was 53 years, and 64.5% was male. The underlying disease included AML/MDS, ALL, NHL/HL, and other diseases is 68.6%, 16.5%, 6.6%, and 8.3%, respectively. The group (N=50) with EBV DNA quantification higher than 1000 copies/mL had a higher percentage of ATG use than the group without it (52.0% vs 11.3%, p<0.001). In cases with EBV reaching >1000 copies/mL, 5/50 (10%) cases developed LPD and 6/50 (12%) cases used rituximab. IMMs reduction could be done after maximum EBV increase in 41/50 (82%) cases. And 30/50 (60%) cases could be achieved a 50% dose reduction or no restarting of IMMs within three months after maximum EBV increases. In cases in which EB virus DNA quantification reached >1000 copies/mL in WB, when stratified by the presence or absence of achievement of less than half IMMs within three months of maximum DNA detection, patients with the achievement of IMMs rapid dose reduction tended to have longer overall survival, OS (not reached vs 5.4 months, p＜0.001. Figure 1) and disease-free survival, DFS (88.4 months vs 5.3 months, p＜0.001). Moreover, rapid (in three months) IMMs dose reduction after increased EBV had significantly longer OS compared to those who can’t on multivariate analysis (hazard ratio: 4.07, 95% CI 2.28-7.27, p < 0.001). Although there were five cases of long-term persistence of high EBV viral load despite the end of IMMs, these cases coexisted peacefully with the patient without treatment with rituximab or chemotherapy. (The minimum number of days after SCT at maximum EBV increase was 266 days, and the maximum was 1143 days.) Summary/Conclusion: After detecting high EB virus viral load, OS and DFS were significantly inferior in patients who could not reduce IMMs by half or less within three months compared to those who could.Keywords: Epstein barr virus, Allogeneic hematopoietic stem cell transplant, Lymphoproliferative disorder

Chronic active Epstein-Barr virus (CAEBV) disease is more likely to occur when a patient is on immunosuppressive therapy for any disease or is susceptible to infection, and the prognosis is poor without appropriate treatment, including hematopoietic stem cell transplantation (HSCT). In addition to HSCT, several other chemotherapy regimens have been reported, but all of them are difficult to maintain in remission. Without HSCT, survival rates have been reported to be 50% in 5 years and 25% in 15 years. This is a report of a 13-year-old boy who developed CAEBV disease during cyclosporine A (CyA) treatment for the steroid-dependent nephrotic syndrome (SDNS). Since SDNS precluded HSCT or chemotherapy, CyA was tapered off based on the belief that alleviating his immunosuppressed state would decrease the CAEBV disease. We decided to gradually reduce the CyA dose to activate T-cell immunity, while periodically monitoring the EBV viral load. Finally, we found an appropriate dose that could suppress both CAEBV disease and SDNS, and it lasted for more than 9 years. No case has been reported to date in which a patient developed CAEBV disease while receiving immunosuppressive drugs for the primary disease, and both diseases were controlled only by reducing the dose of immunosuppressive drugs. In this report, we show that dose reduction of immunosuppressive agents without chemotherapy or HSCT is an effective option for the treatment of CAEBV disease in patients receiving immunosuppressive agents.

We herein describe the case of a 52-year-old male patient who presented with fever, arthritis, and neutrophilic dermatosis in 2013 and subsequently experienced macrophage activation syndrome treated with high-dose glucocorticoid therapy. Due to the persistent symptoms refractory to several immunomodulatory and immunosuppressive (IS) drug therapies with dapsone, methotrexate, tacrolimus, infliximab (IFX), and tocilizumab (TCZ), he received prednisolone (PSL) ≥20 mg/day to suppress disease activity. In 2017, Epstein-Barr virus (EBV)-associated haemophagocytic lymphohistiocytosis (HLH) was diagnosed and initially treated with immunochemotherapy consisting of dexamethasone, cyclosporine (CyA), and etoposide (ET). Because of the suboptimal response to the initial therapy, cytoreduction therapy consisting of CHOP (combination chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine, and PSL) was administered. This regimen improved the EBV-associated HLH. Later, the patient's condition stabilised with methylprednisolone 1 mg/day and CyA 100 mg/day. In 2022, ubiquitylation-initiating E1 enzyme (UBA1) variant analysis using Sanger sequencing of peripheral blood leukocytes detected a previously reported somatic variant (NM_003334.3: c.118-1G>C), confirming the diagnosis of vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome. The clinical course in the present case suggested the possibility that CHOP could be a potential treatment option for VEXAS syndrome, in the pathophysiology of which the expansion of clones with UBA1 variant seems to play a pivotal role.

Epstein-Barr virus-associated lymphoproliferative disorders (EBV-LPD) is a rare disease characterized by persistent or recurrent inflammation accompanied by EBV infection of T or NK cells that is not self-limiting, and it is fatal, if untreated. After receiving the first dose of the BNT162b2 mRNA COVID-19 vaccine, a 79-year-old male presented to the hospital with a 2-week history of fever. Laboratory results indicated pancytopenia, elevated liver transaminase levels, hyperferritinemia, and hypofibrinogenemia. Computed tomography revealed hepatosplenomegaly, but lymphadenopathy was not observed. A bone marrow biopsy, a random skin biopsy, and a liver biopsy revealed no malignancy, but an infectious evaluation revealed EBV viremia (5.19 Log IU/ml). Flow cytometry and RT-PCR revealed that the EBV genome was localized in NK cells, suggesting the diagnosis of EBV-NK-LPD. We administered prednisolone, intravenous immunoglobulin, and etoposide, but the EBV-DNA load failed to decrease, and he died 2 months later. Recently, case reports of COVID-19 vaccination-related hemophagocytic lymphohistiocytosis have been published. Although the mechanisms and risk factors for EBV-LPD after BNT162b2 mRNA COVID-19 vaccination remain unknown, it is important to note the possibility of reactivation of EBV after COVID-19 vaccination to initiate early and targeted therapy.

Aggressive natural killer cell leukemia (ANKL) is a rare lymphoid neoplasm frequently associated with Epstein-Barr virus, with a disastrously poor prognosis. Owing to the lack of samples from patients with ANKL and relevant murine models, comprehensive inves-tigation of its pathogenesis including the tumor microenvironment (TME) has been hin-dered. Here we established 3 xenograft mice derived from patients with ANKL (PDXs), which enabled extensive analysis of tumor cells and their TME. ANKL cells primarily engrafted and proliferated in the hepatic sinusoid. Hepatic ANKL cells were characterized by an enriched Myc-pathway and proliferated faster than those in other organs. Inter-actome analyses and in vivo CRISPR-Cas9 analyses revealed transferrin (Tf)-transferrin receptor 1 (TfR1) axis as a potential molecular interaction between the liver and ANKL. ANKL cells were rather vulnerable to iron deprivation. PPMX-T003, a humanized anti-TfR1 monoclonal antibody, showed remarkable therapeutic efficacy in a preclinical setting using ANKL-PDXs. These findings indicate that the liver, a noncanonical hematopoietic organ in adults, serves as a principal niche for ANKL and the inhibition of the Tf-TfR1 axis is a promising therapeutic strategy for ANKL.

The proportion of pediatric cases with severe acute hepatitis of unknown etiology in the coronavirus disease 2019 era was higher than that in the pre-coronavirus disease 2019 era in Japan's largest pediatric transplant center. Further research and monitoring are essential.

Chronic active Epstein–Barr virus disease (CAEBV), formerly named chronic active Epstein–Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein–Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000 IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

Reactivation of Epstein-Barr virus (EBV) has been considered a very rare event among patients on immunomodulatory drugs (IMiDs) such as lenalidomide, and an association between the two has not well been recognized. We have recently experienced a rare case of multiple myeloma in which the patient had suffered EBV reactivation during long-term lenalidomide maintenance therapy. The patient subsequently developed EBV-associated lymphoproliferative disease (LPD) as well as EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), which was fatal despite intensive treatment. Although rare, clinicians should be aware that such fatal EBV reactivation could occur as a minor yet critical complication of long-term maintenance therapy with IMiDs in multiple myeloma patients. Regular monitoring and early detection of EBV reactivation would be beneficial for these patients, so that proper diagnostic examinations can be initiated without delay.

Systemic chronic active Epstein-Barr virus infection (sCAEBV) is an intractable disease that present activated EBV-infected T- or NK-cells and their clonal proliferation. When inflammatory symptoms persist and proceed, a lethal complication of hemophagocytic lymphohistiocytosis (HLH) develops, but its biomarker to represent the pathophysiology and an effective agent to cure have not been developed as of today. It is known that interferon-γ (IFN-γ) level in the peripheral blood increases in HLH correlatedly with the disease condition and that antagonistic anti-IFN-γ antibody is effective against HLH. We examined the plasma level of IFN-γ to investigate its role in the disease condition of sCAEBV. sCAEBV was diagnosed based on the criteria conforming to the definition of sCAEBV in the WHO classification issued in 2017. As it was previously reported, disease activity was defined as the condition positive for any one of the followings: fever, liver dysfunction, progressive skin lesions, vasculitis, and uveitis. Eighteen sCAEBV patients were examined. Their plasma IFN-γ levels were significantly higher than those of healthy donors. The levels in sCAEBV patients with disease activity were higher than those without disease activity. The mRNA expression of IFNG was detected in EBV-infected cells of all patients. We also detected a correlation between plasma IFN-γ levels and mRNA levels of EBV-infected cells in peripheral blood mononuclear cells. These results suggest that EBV-infected cells produce IFN-γ in sCAEBV. Although the difference was not significant, the patients whose plasma IFN-γ levels at diagnosis were higher than 40 pg/mL tended to result in poorer survival than those with lower levels. We concluded that plasma IFN-γ is a potential biomarker that indicates disease activity of sCAEBV. Further study shall confirm its significance.

Background: Systemic chronic active Epstein-Barr virus disease (sCAEBV) is a rare EBV-positive T- or NK-lymphoproliferative disease. Although the only curative treatment for sCAEBV available now is allogeneic hematopoietic stem cell transplantation (allo-HSCT), the presence of disease activity, persistent inflammation, at the time of allo-HSCT is associated with poor outcomes (Am J Hem.2022, 97, p780). STAT3 is constitutively activated contributing to cytokine production and cell survival of EBV-infected cells in sCAEBV (Oncotarget. 2019, 9, p31077). Thus, STAT3 inhibition by ruxolitinib, a JAK1/2 inhibitor, may be effective against disease activity of sCAEBV. Methods: We conducted an investigator-initiated trial of open-label, phase 2, prospective and multicenter to assess the efficacy and safety of ruxolitinib in sCAEBV patients with disease activity. The diagnostic criteria were as follows: elevated EBV-DNA load in the peripheral blood (PB) (>102.5 copies/µg DNA); EBV infected T or NK cells detected in affected tissues or PB; systemic inflammatory symptoms persisting for more than three months; exclusion of other possible diagnoses, such as immune deficiencies, autoimmune diseases, or lymphoma (Blood adv. 2021, 4, p2918). sCAEBV patients ≥13 y.o. with fever (≥ 37.5 ºC), and/or liver dysfunction (ALT ≥ 2.0 × ULN) were enrolled. Anti-VCA-IgM-positive patients were excluded. The initiation dose of ruxolitinib was 5-20 mg twice a day determined by the platelet count in PB. The treatment effects were classified as complete response (CR), partial response (PR), progressive disease (PD), and stable disease (SD). CR was defined as the disappearance of all the elements of disease activity such as fever, liver dysfunction, uveitis, progressive skin lesions, and vasculitis. PR was defined as the disappearance of at least one of the elements listed above. PD was defined as the conversion to active disease, exacerbation of active disease, or the development of overt T- or NK-cell lymphoma. SD was defined as presenting no progression. Ruxolitinib was administered for eight weeks. If CR was observed and allo-HSCT was scheduled, ruxolitinib was terminated early even if these events had occurred within less than eight weeks after initiating investigational drug administration. The primary endpoint of efficacy assessments was CR rate at eight weeks after the initiation of drug administration or at the time of early termination. Safety was assessed based on the frequency of adverse events defined by Common Terminology Criteria for Adverse Events, version 4.0. Results: Nine patients were enrolled between January 2019 and August 2021; five males and four females aged 13-64 y.o.; median age of 40 y.o. The types of EBV-infected cells were as follows: four were CD4, one was CD8, and four were CD56. Seven patients completed the study. Five among them received ruxolitinib for eight weeks and were treated as outpatients. Two patients fulfilled the criteria of early termination and each was treated for 35 and 12 days. The responses are shown in the figure. CR rate and OR rate after eight weeks or at early termination, the primary and the secondary endpoints were 28.6% (2/7) and 42.9% (3/7), respectively. No one showed progressive disease. One patient developed a grade 4 adverse event of oral bleeding during the treatment and resulted in discontinuing the administration of ruxolitinib on day 13. Seven patients received allo-HSCT. Five patients achieved undetectable level of EBV-DNA PB after allo-HSCT. Conclusion: The results indicate that ruxolitinib has demonstrated encouraging effects and is a potent therapeutic reagent against sCAEBV with active disease. Further analysis shall complete its assessment. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal