Advances in the Study of Chronic Active Epstein-Barr Virus Infection: Clinical Features Under the 2016 WHO Classification and Mechanisms of Development

A differential diagnosis method for systemic CAEBV and the prospect of EBV-related immune cell markers via flow cytometry

Chronic active Epstein-Barr virus (CAEBV) infection of the T-cell or Natural killer (NK)-cell type, systemic form (systemic CAEBV or sCAEBV) was defined by the WHO in 2017 as an EBV-related lymphoproliferative disorder and is listed as an EBV-positive T-cell and NK-cell proliferation. The clinical manifestations and prognoses are heterogeneous. This makes systemic CAEBV indistinguishable from other EBV-positive T-cell and NK-cell proliferations. Early diagnosis of systemic CAEBV and early hematopoietic stem cell transplantation can improve patient prognosis. At present, the diagnosis of systemic CAEBV relies mainly on age, clinical manifestations, and cell lineage, incurring missed diagnosis, misdiagnosis, long diagnosis time, and inability to identify high-risk systemic CAEBV early. The diagnostic methods for systemic CAEBV are complicated and lack systematic description. The recent development of diagnostic procedures, including molecular biological and immunological techniques such as flow cytometry, has provided us with the ability to better understand the proliferation of other EBV-positive T cells and NK cells, but there is no definitive review of their value in diagnosing systemic CAEBV. This article summarizes the recent progress in systemic CAEBV differential diagnosis and the prospects of flow cytometry.

Highly sensitive detection of Epstein-Barr virus-infected cells by EBER flow FISH

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.

Clinical Characteristics of Peripheral Lymphocyte Subtypes in Chronic Active Epstein-Barr Virus Infection

BACKGROUND

We aimed to analyze the clinical characteristics of peripheral Epstein-Barr virus (EBV)-infected lymphocyte subtypes in children with chronic active EBV infection (CAEBV).

METHODS

The levels of peripheral EBV infection of CD4+ T cells, CD8+ T cells, and CD56+ natural killer (NK) cells were determined by flow cytometry and quantitative polymerase chain reaction (qPCR) in patients with CAEBV from July 2017 to July 2022.

RESULTS

In total, 112 children with CAEBV were evaluated. Of these, CD4+ type, CD8+ type, and CD56+ type were defined in 44, 21, and 47 patients, respectively. Patients with CD8+ T-cell type had a significantly higher frequency of rash, while hepatomegaly was more common in patients with CD4+ T-cell type. Generally, patients with CD8+ T-cell type had the lowest overall survival rate (P = .017). Patients treated with chemotherapy and hematopoietic stem cell transplantation (HSCT) had a better prognosis (P = .001). In multivariate analysis, rash, hemophagocytic lymphohistiocytosis, CD8+ T-cell type, and no decrease of plasma EBV-DNA after treatment were independent indicators of poor prognosis (P = .002, .024, .022, and .012, respectively).

CONCLUSIONS

In children with CAEBV, rash was more frequent in patients with CD8+ T-cell type, whereas patients with CD4+ T-cell type were more likely to develop hepatomegaly. Patients with CD8+ T-cell type had a poor prognosis despite receiving chemotherapy or further HSCT.

Novel plasma microRNA expression features in diagnostic use for Epstein-Barr virus-associated febrile diseases

Background

Epstein-Barr virus (EBV) is widely infected in humans and causes various diseases. Among them, microRNAs of EBV play a key role in the progression of EBV-associated febrile diseases. There're few specific indicators for rapid differential diagnosis of various febrile diseases associated with EBV, and the lack of more reliable screening methods with high diagnostic utility has led to spaces for improvement in the accurate diagnosis and efficient treatment of relevant patients, making EBV infection a complicated clinical problem. With recent advances in plasma microRNA testing, the apparent presence of EBV microRNAs in plasma can help screen for EBV infection. The gene networks targeted by these microRNAs can also indicate potential biomarkers of EBV-associated febrile diseases. This study aimed to identify some novel miRNAs as potential biomarkers for early diagnosis of respectively EBV-associated febrile diseases.

Materials and methods

A total of 110 participants were recruited for this task. First, we performed high-throughput sequencing and preliminary PCR validation of differentially expressed miRNAs in 15 participants with EBV-associated fever (divided into common EBV carriers), infectious mononucleosis (IM) and chronic active EBV infection (CAEBV), EBV-associated Hemophagocytic Lymphohistiocytosis group (EBV-HLH), and 3 healthy individuals. After a comprehensive analysis, 10 miRNAs with abnormal expression were screened, and then qRT-PCR was performed in the rest of 95 participants to detect the validation of miRNAs expression in plasma samples. Thereafter, we further investigated their potential for clinical application in EBV-related febrile diseases by using a combination of Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and Protein-protein interaction network analysis.

Results

Through identification and detailed analysis of the obtained data, we found significant differences in the expression of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p in blood samples from patients with different EBV-related febrile diseases. We found that the expression levels of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p in plasma are indicative of determining different disease types of EBV-related febrile diseases, while EBV-miR-BART22 and EBV-miR-BART2-3p may be potential therapeutic targets.

Conclusion

The expression levels of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p suggest that they may be used as transcriptional features for early differential diagnosis of EBV-related febrile diseases, and EBV-miR-BART22 and EBV-miR-BART2-3p may be potential therapeutic targets.

Epstein-Barr virus-associated B-cell lymphoproliferative disorder meeting the definition of CAEBV B cell disease: a case report

BACKGROUND

Chronic active Epstein-Barr virus infection (CAEBV) is a systemic EBV-positive lymphoproliferative disorder (EBV-LPD) considered to be associated with a genetic immunological abnormality, although its cause is still unclear. EBV is usually detected in T cells or NK cells in CAEBV patients with only a few cases involving B cells described in East Asia, which may be due to differences in genetic and environmental factors.

CASE DESCRIPTION

A 16-year-old boy who seemed to be diagnosed as CAEBV of B cell type was studied. The patient had IM-like symptoms persisting for more than 3 months, high levels of EBV DNA in the PB, and positive EBER in situ hybridization in B cells. In addition, to exclude underlying genetic disorders, we performed next-generation sequencing (NGS) and whole-exome sequencing (WES), which identified the missense mutation in PIK3CD (E1021K), ADA (S85L) and CD3D (Q140K) in the patient while no same genetic mutation was detected in his parents and sister. However, there is no diagnosis of CAEBV of B cell type in the most recent World Health Organization classification of tumors of hematopoietic and lymphoid tissues, therefore we finally diagnosed this patient as EBV-B-LPD.

CONCLUSIONS

This study shows a rare case of a patient meeting the definition of CAEBV B-cell disease in East Asia. Meanwhile, the case indicates that the missense mutation and the disease are related.

Fas/FasL and Complement Activation are Associated with Chronic Active Epstein-Barr Virus Hepatitis

BACKGROUND AND AIMS

Chronic active Epstein-Barr virus hepatitis (CAEBVH) is a rare and highly lethal disease characterized by hepatitis and hepatomegaly. This study aimed to investigate the clinicopathological features and pathogenic mechanisms of CAEBVH.

METHODS

Ten patients with confirmed Epstein-Barr virus hepatitis infection were enrolled. The clinicopathological characteristics of these patients were summarized and analyzed. Flow cytometry was utilized to detect peripheral blood immune cell phenotypes and whole exome sequencing was used to explore pathogenic genetic mechanisms. Lastly, immunohistochemical staining was employed to verify pathogenic mechanisms.

RESULTS

Clinical features observed in all Epstein-Barr virus hepatitis patients included fever (7/10), splenomegaly (10/10), hepatomegaly (9/10), abnormal liver function (8/10), and CD8⁺ T cell lymphopenia (6/7). Hematoxylin and eosin staining revealed lymphocytic infiltration in the liver. Positive Epstein-Barr virus-encoded small RNA in-situ hybridization (EBER-ISH) of lymphocytes of liver tissues was noted. Whole exome sequencing indicated that cytotoxic T lymphocytes and the complement system were involved. The expression of CD8, Fas, FasL, and Caspase-8 expression as well as apoptotic markers was enhanced in the Epstein-Barr virus hepatitis group relative to the controls (p<0.05). Lastly, Complement 1q and complement 3d expression, were higher in CAEBVH patients relative to controls (p<0.05).

CONCLUSIONS

CAEBVH patients developed fever, hepatosplenomegaly, and lymphadenopathy. Histopathological changes were a diffuse lymphocytic sinusoidal infiltrate with EBER-ISH positivity. Fas/FasL and complement activation were involved in CAEBVH patients.

Chronic Active Epstein-Barr Virus (EBV) Infection Controlled by Allogeneic Stem Cell Transplantation and EBV-Specific T Cells

We report sustained remission of chronic active Epstein-Barr virus (EBV) infection in a 27-year-old female patient treated with third-party EBV-specific T cells followed by allogeneic hematopoietic stem cell transplantation (HSCT). The viremia cleared after administration of anti-T-lymphocyte globulin for graft-versus-host disease (GvHD) prophylaxis. Subsequent expansion of EBV-infected host T cells was controlled by transfusion of donor-derived EBV-specific T cells.

Outcomes of programmed death protein-1 inhibitors treatment of chronic active Epstein Barr virus infection: A single center retrospective analysis

Introduction

Chronic active Epstein-Barr virus (CAEBV) disease is a high-mortality disease, which is characterized by persistent infectious mononucleosis-like symptoms. There is no standard treatment for CAEBV and allogeneic hematopoietic stem cell transplantation (HSCT) was considered the only potentially therapeutic approach. PD-1 inhibitors have achieved high response in many Epstein-Barr virus-related diseases. In this single-center retrospective analysis, we report the outcomes of PD-1 inhibitors treatment of CAEBV.

Methods

All CAEBV patients without hemophagocytic lymphohistiocytosis (HLH), who were treated with PD-1 inhibitors in our center between 6/1/2017 and 12/31/2021, were retrospectively analyzed. The efficacy and safety of the PD-1 inhibitors were evaluated.

Results

Among the sixteen patients with a median age at onset of 33 years (range, 11-67 years), twelve patients responded to PD-1 inhibitors and the median progression-free survival (PFS) was 11.1 months (range, 4.9-54.8 months). Three achieved clinical complete response (clinical CR), as well as molecular CR. Five patients achieved and remained partial response (PR), and four converted from PR to no response (NR). For three CR patients, the median time and cycles from the first application of PD-1 inhibitor to clinical CR were 6 weeks (range, 4-10 weeks) and 3 cycles (range, 2-4 cycles), and molecular CR was achieved after a median of 16.7 weeks (range, 6.1-18.4 weeks) and 5 cycles (range, 3-6 cycles) of PD-1 inhibitor infusion. No immune-related adverse events have been observed except for one patient who suffered immune-related pancreatitis. There was no correlation of treatment outcome with blood count, liver function, LDH, cytokine or ferritin levels. NK cell function, PD-L1 expression in tumor tissue and gene mutation possibly correlated with treatment response.

Discussion

In patients with CAEBV, PD-1 inhibitors have tolerable toxicity and comparable outcomes while improving quality of life and financial toxicity. Larger prospective studies and longer follow-up time is needed to be conducted.

Virological Markers in Epstein–Barr Virus-Associated Diseases

Epstein–Barr virus (EBV) is an oncogenic virus infecting more than 95% of the world’s population. After primary infection—responsible for infectious mononucleosis in young adults—the virus persists lifelong in the infected host, especially in memory B cells. Viral persistence is usually without clinical consequences, although it can lead to EBV-associated cancers such as lymphoma or carcinoma. Recent reports also suggest a link between EBV infection and multiple sclerosis. In the absence of vaccines, research efforts have focused on virological markers applicable in clinical practice for the management of patients with EBV-associated diseases. Nasopharyngeal carcinoma is an EBV-associated malignancy for which serological and molecular markers are widely used in clinical practice. Measuring blood EBV DNA load is additionally, useful for preventing lymphoproliferative disorders in transplant patients, with this marker also being explored in various other EBV-associated lymphomas. New technologies based on next-generation sequencing offer the opportunity to explore other biomarkers such as the EBV DNA methylome, strain diversity, or viral miRNA. Here, we review the clinical utility of different virological markers in EBV-associated diseases. Indeed, evaluating existing or new markers in EBV-associated malignancies or immune-mediated inflammatory diseases triggered by EBV infection continues to be a challenge.

PD-1 blockade and lenalidomide combination therapy for chronic active Epstein-Barr virus infection

OBJECTIVES

Chronic active Epstein-Barr virus infection (CAEBV) is a prototype of EBV-associated T-or NK-cell lymphoproliferative diseases. It is a disease with poor outcome. Almost all current therapies are ineffective except of allogeneic hematopoietic stem cell transplantation.

METHODS

We investigated the efficacy and safety of programmed death 1 (PD-1) blockade (Sintilimab), combined with lenalidomide, which is an immunomodulatory drug, in an open-label, single-center, prospective study involving CAEBV patients. PD1 blockade 2mg/kg was given every two weeks by intravenous infusion on day 1, and lenalidomide 5mg (age<18 years)/10mg (age ≥ 18 years) was given orally once a day on day 1-14.

RESULTS

As of Nov 15, 2020, 34 patients were enrolled. As of the Feb 1, 2021 analysis cut-off date, 24 cases completed at least 3 courses and were assessed for efficacy. The overall response rate is 54.2% (13/24, 45.8% complete response; 8.3% partial response). EBV-DNA copies in PBMC decreased significantly (p = 0.002). The proportion of CD8+T cells in lymphocytes increased (p = 0.007). The comparative analysis between response group and non-response group showed the proportion of Effector Memory CD8+ T cells and cytokines of CTLs activation (IFN-γ, CD27, CD30, MIG, IP-10) increased significantly in Response-group after treatment. Whole-exome sequencing generated from peripheral blood and saliva samples reveal that Non-Response group had a higher somatic mutational load of copy number variation in background. With a median follow-up time of 17.8 months, 22 of 24 patients were alive with an estimated survival probability of 91.3% at 1 year. All 34 patients were assessed for safety evaluation. The possible drug-related adverse events were reported in 17 (50%) patients.

CONCLUSIONS

PD-1 blockade combined with lenalidomide was an effective and safe therapy for CAEBV patients. The significant therapeutic effect and the different characteristics between response and non-response group, provides a possible predictive value for CAEBV treatment option.

Chronic Active Epstein-Barr Virus Infection With Central Nervous System Involvement in Children: A Clinical Study of 22 Cases

OBJECTIVE

To analyze the clinical features, treatment, and prognosis of chronic active Epstein-Barr virus infection (CAEBV) with central nervous system (CNS) involvement in children.

METHODS

Patients with CAEBV admitted to Beijing Children's Hospital, Capital Medical University, were enrolled in this study from January 2017 to December 2020. They were divided into a CNS group and a non-CNS group based on the presence of CNS involvement.

RESULTS

Twenty-two patients developed CNS disease, accounting for 23.9% (22/92) of CAEBV patients in the same period. Of these, only 2 of 22 patients presented initially with neurologic symptoms in the CNS group, and they all improved after treatment. Cerebrospinal fluid (CSF) examination demonstrated normal protein concentration and cell number in all patients with CNS involvement. Only 7 patients were positive for CSF EBV-DNA. Twenty-one patients had neuroimaging abnormalities, such as white matter signal abnormalities, encephalography or calcification. In the CNS group, 7 (31.8%) patients died, including 5 who died of active hemophagocytic lymphohistiocytosis, 1 died of unrelated causes, and 1 died of respiratory failure caused by pulmonary lymphoproliferative disease progression after transplantation. The 3-year overall survival was lower in the CNS group than in the non-CNS group (63.6% ± 11.9% versus 86.9% ± 4.1%, P = 0.027). Hemophagocytic lymphohistiocytosis (HLH) is an independent risk factor for CNS involvement in patients with CAEBV (OR = 2.946, 95% CI: 1.042-8.335, P = 0.042). Compared with the non-CNS group, blood EBV-DNA loads and CD4+/CD8+ ratio of T lymphocytes in the CNS group were higher (P < 0.001), while fibrinogen levels and natural killer (NK)-cell activity were lower (P = 0.047). Children with CAEBV were more likely to develop CNS diseases with low NK-cell activity (NK-cell activity < 14.00%, P = 0.023) or high alanine aminotransferase (ALT) levels (ALT levels > 40 U/L, P = 0.032).

CONCLUSION

CAEBV with CNS involvement has nonspecific clinical manifestations, laboratory data, neuroimaging but has a worse prognosis. Blood fibrinogen levels and NK-cell activity in CAEBV children with CNS involvement are lower than in those without CNS involvement. In contrast, blood EBV-DNA loads and CD4+/CD8+ ratio of T lymphocytes are higher. Children with CAEBV who presented with HLH, NK-cell activity <14.00%, serum ALT >40 U/L and high-blood EBV-DNA loads are prone to develop CNS diseases.

Case report: Immune modulation after PD-1 inhibitor therapy in a patient with extranodal NK/T-cell lymphoma secondary to chronic active Epstein-Barr virus disease unveiled by single-cell transcriptomics

Chronic active Epstein-Barr virus disease (CAEBV) is a systemic lymphoproliferative disorder that is closely linked to Epstein-Barr virus (EBV) infection. The clinical course and severity of CAEBV can vary, and in some cases, it can progress to overt lymphoma, which is characterized by extranodal natural killer/T-cell lymphoma (ENKTL) and has a poor clinical outcome. Although anti-programmed cell death protein-1 (PD-1) therapy has shown effectiveness in some patients with EBV-associated disease, it has been less successful in others, and the exact mechanism of action of PD-1 inhibitor therapy in these diseases remains unclear. In this report, we describe a patient who was diagnosed with ENKTL secondary to CAEBV and experienced rapid disease progression accompanied by hyperinflammation after receiving PD-1 inhibitor therapy. Single-cell RNA sequencing revealed a significant increase in the patient's lymphocyte count, especially in natural killer cells, with increased activity following PD-1 inhibitor therapy. This case raises questions about the efficacy and safety of PD-1 inhibitor therapy in patients with EBV-associated diseases.

Risk of malignancy following exposure to Epstein-Barr Virus associated infectious mononucleosis: A nationwide population-based cohort study

Purpose

Epstein-Barr virus (EBV) infection has been shown to contribute to oncogenesis and often causes acute clinical manifestation of Infectious mononucleosis (IM). It is unknown whether IM could increase the risk of subsequent malignancies. We aimed to evaluate the association of IM caused by EBV (EBV-IM) with overall and subtypes of malignancy in a large population-based cohort study.

Methods

This study included 1,419,407 individuals born in Denmark between 1973 and 2016 identified from national registers and 23,057 individuals had IM. The 5,394 of them had confirmed EBV-IM and they were birth date- and sex- matched (1:63) to 1,396,350 non-IM individuals. Cox regression was used to examine the associations of EBV-IM with malignancy.

Results

Individuals with a history of confirmed EBV-IM had an 88% increased overall risk of malignancy (hazard ratio [HR]:1·88, 95% confidence interval [CI]: 1·42-2·49) and a five-fold risk of hematologic malignancies (HR 5·04, 95% CI: 3·07-8·25), compared to those without IM. Similar estimates were observed in the sibling analysis. The overall risk of malignancy was greater for EBV-IM with complications (HR 8·93, 95% CI: 3·35-23·81) than that for EBV-IM without complications (HR 1·35, 95% CI: 1·20-1·53). EBV-IM duration was related to increased risk of malignancy in a dose-response way. Notably, the significant elevated risk of overall malignancy was observed in the first two years after EBV-IM onset (rate ratio [RR] 4·44, 95% CI: 2·75-7·17) and attenuated thereafter.

Conclusion

EBV-IM was associated with an increased risk in malignancy, particularly hematologic malignancies and in the first two years following IM exposure. Our findings suggest an important time-window for early screening of the EBV-attributed malignancy.

Massive pericardial effusion due to chronic active Epstein-Barr virus infection successfully treated with PD-1 blockade: A case report

RATIONALE

Chronic active Epstein-Barr virus (EBV) infection (CAEBV) is a rare but life-threatening EBV-positive lymphoproliferative disorder. Currently, treatment options for CAEBV are limited. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only way to cure CAEBV. Here, we report a rare case of CAEBV manifesting as massive pericardial effusion that was successfully treated with programmed cell death protein-1 (PD-1) blockade immunotherapy.

PATIENT CONCERNS

A 36-year-old woman with intermittent chest distress and dyspnea for 8 months was admitted to our center on October 25, 2021. Laboratory tests showed leukocytopenia and elevated liver enzyme levels. Initial echocardiography revealed massive pericardial effusion.

DIAGNOSIS

High levels of EBV-DNA were detected in the pericardial fluid by metagenomic next-generation sequencing. The pathological diagnosis of her left inguinal lymph node and skin lesions revealed systemic CAEBV.

INTERVENTIONS

The patient received sintilimab injection at a dose of 200 mg every 2 weeks in combined with lenalidomide 10 mg once daily.

OUTCOMES

The patient achieved complete resolution of pericardial effusion 5 months after PD-1 blockade immunotherapy without apparent adverse effects.

LESSONS

CAEBV is a rare but life-threatening EBV-positive lymphoproliferative disease. We present a rare case of massive pericardial effusion caused by systemic CAEBV, which was successfully treated with sintilimab. This case highlights the promising curative effect of PD-1 blockade immunotherapy in systemic CAEBV, especially for patients not suitable for allo-HSCT.

A rare B-cell type chronic active Epstein-Barr virus infection patient mimicking lymphoma on 18F-FDG PET/CT and literature review

A 13-year-old girl suffered from worsen snoring and persistent bilateral nasal congestion for one year. Paranasal sinus computed tomography (CT) and magnetic resonance imaging (MRI) found nasopharyngeal passages and sinus were occupied with soft tissues and bilateral neck enlarged lymph nodes 6 months ago. Tumor markers were normal. The titers of anti-Epstein-Barr virus (EBV) IgM, anti-EBV IgG, early antigen (EA) IgG, and Epstein-Barr nuclear antigen (EBNA) IgG increased. 2-Deoxy-2-[fluorine-18]-fluoro-D-glucose (¹⁸F-FDG) positron emission tomography combined with CT (PET/CT) revealed thickened soft tissues in nasopharynx and oropharynx, enlarged multiple lymph nodes in the neck, bilateral armpits, abdominal cavity and retroperitoneum, and pelvic cavity, diffuse thickening of the gastric wall of the antrum with hypermetabolism. According to the age, situation, regions, and abnormal FDG uptake, an initial diagnosis of EBV-related lymphoma was made. However, the pathological results of the nasopharyngeal mass and the abdominal lymph node confirmed the final diagnosis of a B-cell type chronic active Epstein-Barr virus disease (CAEBV), a rare type of EBV associated lymphoproliferative disorder (LPD). After receiving adoptive immune cells therapy, the EBV load decreased. At present, the patient is being followed up.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2022 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an entity included in the WHO classification of lymphoid neoplasms since 2016. EBV+ DLBCL, NOS, is an aggressive B-cell lymphoma associated with EBV infection, and a poor prognosis with standard chemotherapeutic approaches.

DIAGNOSIS

The diagnosis is made through a careful pathological evaluation. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for percentage of positive cells has not been defined. The differential diagnosis includes plasmablastic lymphoma (PBL), DLBCL associated with chronic inflammation, primary effusion lymphoma (PEL), among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. Therefore, the inclusion of patients in clinical trials when available is recommended. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

Successful HLA-haploidentical stem cell transplantation with post-transplant cyclophosphamide in an older patient with chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus infection (CAEBV) is a subtype of EBV-associated T/NK cell lymphoproliferative disease and is only curable by allogeneic hematopoietic stem cell transplantation. However, finding a human leukocyte antigen (HLA)-matched donor at a suitable time can sometimes be difficult. We report the case of a 60-year-old woman who received prednisolone (PSL) after being diagnosed with autoimmune hepatitis 3 years earlier. She suddenly developed high fever and impaired liver function. Based on a high EBV DNA load in the peripheral blood, CAEBV was diagnosed. The patient was started on cooling therapy with PSL, cyclosporine, and etoposide, which reduced symptoms. Subsequently, she received HLA-haploidentical stem cell transplantation (haplo-SCT) with reduced-intensity conditioning (fludarabine 25 mg/m² for 5 days, melphalan 50 mg/m² for 2 days, and total body irradiation at 2 Gy) and post-transplant cyclophosphamide (PTCy) because she lacked an HLA-matched donor. Liver function was restored, and EBV DNA load in peripheral white blood cells became undetectable. The patient is alive without relapse or severe complications over 1 year after transplantation. To our knowledge, this is the first report of successful haplo-SCT with PTCy for CAEBV. This approach may be an alternative therapeutic option for CAEBV patients lacking an HLA-matched donor.

Case Report: Chronic Active Epstein–Barr Virus Infection With Subcutaneous Nodules and Systemic Damage

Chronic active Epstein–Barr virus (CAEBV) infection is a rare and progressive systemic lymphoproliferative disorder often beginning as an infectious mononucleosis (IM)-like illness. It manifests with fever, splenomegaly, hepatitis, lymphadenopathy, and occasionally cytopenias, pneumonitis, and vasculitis. We report a 23-year-old woman with fever and subcutaneous nodules first appearing on the limbs and then spreading to the body. Peripheral blood EBV antibodies were elevated and EBV-DNA loads significantly increased. A skin and lymph node biopsy identified T cell-based lymphocyte infiltration and EBV-encoded RNA positivity (EBER+). CAEBV was finally diagnosed. During the illness, her disease progressed to hemophagocytic syndrome (HPS). The patient then successfully received an allogeneic hematopoietic stem cell transplantation (HSCT) at 6 months. Current follow-up at 2 years indicated a stable condition and six negative EBV-DNA tests, and we reviewed the clinical manifestations, mechanism, diagnosis and differential diagnosis, treatment, and prognosis of CAEBV. Finally, subcutaneous nodules may occur when CAEBV invades the skin; therefore, clinicians must identify the cause of these nodules early. HSCT is effective but its timing must be appropriate.

Epstein-Barr virus infection associated polymyositis and coronary artery dilation

Background

Epstein-Barr virus (EBV) infects more than 90% of the population worldwide. However, chronic active EBV infection (CAEBV) is one of the EBV-positive T- or NK-lymphoproliferative diseases with high morbidity and mortality. Here, we report a case of a 9-year girl with CAEBV, successively presenting with polymyositis and coronary artery dilation (CAD).

Case presentation

The girl complained of fatigue for more than 1 month. Muscle strength examinations had no abnormal findings. Blood chemistries showed elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatine kinase (CK). Magnetic resonance imaging (MRI) showed spotty high-intensity signals in thigh muscles, and electromyogram suggested myogenic damage. The significant findings were positive EBV antibodies (EBVEA-IgG, EBVCA-IgG, and EBVNA-IgG), increased EBV DNA copies in B, T, and NK cells, and positive EBV-encoded small RNA in biopsy muscle specimen. The girl received ganciclovir, intravenous immunoglobulin, and methylprednisolone, and her symptoms improved. On the 45th day of hospitalization, echocardiograph revealed CAD. She received additional anticoagulants and Tocilizumab. Her condition improved and continued to be followed up at the clinic preparing for hematopoietic stem cell transplantation.

Conclusions

This is the first reported case of CAEBV successively with polymyositis and CAD. This case makes the diagnoses of autoimmune diseases in children more complicated. Careful investigation of hidden CAEBV should be recommended in children with atypical polymyositis or CAD.

EBV associated T- and NK-cell lymphoproliferative diseases: A comprehensive overview of clinical manifestations and novel therapeutic insights

EBV is a ubiquitous virus that infects nearly all people around the world. Most infected people are asymptomatic and do not show serious sequelae, while others may develop Epstein-Barr virus (EBV)-positive T and NK-cell lymphoproliferations characterised by EBV-infected T or NK cells. These disorders are more common in Asian and Latin American people, suggesting genetic predisposition as a contributing factor. The revised WHO classification classifies the lymphoproliferative diseases as: extranodal NK/T-cell lymphoma nasal type (ENKTL), aggressive NK-cell leukemia (ANKL), primary EBV-positive nodal T or NK cell lymphoma (NNKTL), systemic EBV-positive T-cell lymphoproliferative disease of childhood (STCLC), systemic chronic active EBV infection (sys CAEBV), hydroa-vacciniforme (HV) and severe mosquito bite allergy (SMBA). Recent advances in the molecular pathogenesis of these diseases have led to the development of new therapeutic strategies. Due to the infrequency of the diseases and broad clinicopathological overlap, the diagnosis and classification are challenging for both clinicians and pathologists. In this article, we aim to review the recent pathological findings which can be helpful for designing new drugs, clinical presentations and differential diagnoses, and suggested therapeutic interventions to provide a better understanding of these rare disorders.

Genetic errors of immunity distinguish pediatric nonmalignant lymphoproliferative disorders

BACKGROUND

Pediatric nonmalignant lymphoproliferative disorders (PLPDs) are clinically and genetically heterogeneous. Long-standing immune dysregulation and lymphoproliferation in children may be life-threatening, and a paucity of data exists to guide evaluation and treatment of children with PLPD.

OBJECTIVE

The primary objective of this study was to ascertain the spectrum of genomic immunologic defects in PLPD. Secondary objectives included characterization of clinical outcomes and associations between genetic diagnoses and those outcomes.

METHODS

PLPD was defined by persistent lymphadenopathy, lymph organ involvement, or lymphocytic infiltration for more than 3 months, with or without chronic or significant Epstein-Barr virus (EBV) infection. Fifty-one subjects from 47 different families with PLPD were analyzed using whole exome sequencing.

RESULTS

Whole exome sequencing identified likely genetic errors of immunity in 51% to 62% of families (53% to 65% of affected children). Presence of a genetic etiology was associated with younger age and hemophagocytic lymphohistiocytosis. Ten-year survival for the cohort was 72.4%, and patients with viable genetic diagnoses had a higher survival rate (82%) compared to children without a genetic explanation (48%, P = .03). Survival outcomes for individuals with EBV-associated disease and no genetic explanation were particularly worse than outcomes for subjects with EBV-associated disease and a genetic explanation (17% vs 90%; P = .002). Ascertainment of a molecular diagnosis provided targetable treatment options for up to 18 individuals and led to active management changes for 12 patients.

CONCLUSIONS

PLPD defines children at high risk for mortality, and whole exome sequencing informs clinical risks and therapeutic opportunities for this diagnosis.

Haploidentical hematopoietic stem cell transplantation for pediatric patients with chronic active Epstein-Barr virus infection: a retrospective analysis of a single center

BACKGROUND

This study aimed to evaluate the feasibility and clinical effect of haploidentical hematopoietic stem cell transplantation (haplo-HSCT) for the treatment of pediatric patients with chronic active Epstein-Barr virus infection (CAEBV).

METHODS

Children with CAEBV who did not have matched donors and underwent haplo-HSCT in Beijing Children's Hospital, Capital Medical University, from October 2016 to June 2020 were analyzed retrospectively. Data relating to the clinical manifestations, engraftment, and prognosis of the children were extracted from medical records.

RESULTS

Twenty-five patients, including 16 males and 9 females, with an onset age of 5.0 ± 2.6 years and a transplantation age of 6.9 ± 2.9 years, were enrolled in this study. The mean time from diagnosis to transplantation was 3.8 (2.0-40.2) months. The mean observation time was 19.0 ± 12.0 months. Three patients received the reduced intensity conditioning regimen, and the remaining patients all received the modified myeloablative conditioning regimen. By the end of the follow-up, 23 patients were characterized by disease-free survival (DFS), 22 were characterized by event-free survival (EFS), and two died. One of the patients died of thrombotic microangiopathy (TMA), and another died of graft versus host disease (GVHD); this patient discontinued the treatment for economic reasons. The 3-year overall survival (OS) rate was estimated to be 92.0% ± 5.4%, and the 3-year EFS rate was estimated to be 87.4% ± 6.8%. All active patients survived after HSCT event-free. Acute GVHD degrees 1-3 were observed in ten patients (40.0%), and degree IV was observed in six (24.0%), who were all cured except for one patient. Chronic GVHD was observed in nine (36.0%), and most of these cases were mild. The incidence of TMA and veno-occlusive disease (VOD) was 28.0% and 4.0%.

CONCLUSIONS

Haploidentical hematopoietic stem cell transplantation is safe and effective in the treatment of pediatric CAEBV and can be used as an alternative therapy without matched donors or emergency transplantation. Patients with active disease before HSCT also benefited from haplo-HSCT. Haplo-HSCT requires careful monitoring for complications, such as GVHD and TMA. Early detection of TMA and timely treatment can reduce mortality and can improve the survival rate.

EBV-Driven Lymphoproliferative Disorders and Lymphomas of the Gastrointestinal Tract: A Spectrum of Entities with a Common Denominator (Part 3)

EBV is the first known oncogenic virus involved in the development of several tumors. The majority of the global population are infected with the virus early in life and the virus persists throughout life, in a latent stage, and usually within B lymphocytes. Despite the worldwide diffusion of EBV infection, EBV-associated diseases develop in only in a small subset of individuals often when conditions of immunosuppression disrupt the balance between the infection and host immune system. EBV-driven lymphoid proliferations are either of B-cell or T/NK-cell origin, and range from disorders with an indolent behavior to aggressive lymphomas. In this review, which is divided in three parts, we provide an update of EBV-associated lymphoid disorders developing in the gastrointestinal tract, often representing a challenging diagnostic and therapeutic issue. Our aim is to provide a practical diagnostic approach to clinicians and pathologists who face this complex spectrum of disorders in their daily practice. In this part of the review, the chronic active EBV infection of T-cell and NK-cell type, its systemic form; extranodal NK/T-cell lymphoma, nasal type and post-transplant lymphoproliferative disorders are discussed.

Peripheral blood lymphocyte counts in patients with infectious mononucleosis or chronic active Epstein-Barr virus infection and prognostic risk factors of chronic active Epstein-Barr virus infection

OBJECTIVE

To explore the peripheral blood lymphocyte counts and analyze the prognostic risk factors for the death in patients with chronic active Epstein-Barr virus (CAEBV) infection.

METHODS

Clinical data of 64 patients infected with CAEBV (CAEBV group) and 64 patients with infectious mononucleosis (IM group) in our hospital were retrospectively analyzed. Meanwhile, 64 healthy individuals came for physical examination were enrolled in the control group. The three groups were compared for white blood cell count, lymphocyte count, and levels of peripheral blood NK cells, B cells, CD3⁺, CD4⁺, CD8⁺, CD4⁺CD28⁺, CD8⁺CD28⁺, CD4⁺CD25⁺, DR⁺CD8⁺, CD38⁺CD8⁺, CD4⁺ and CD8⁺ naive T cells and subsets of memory T cells. Patients infected with CAEBV were further divided into a survival subgroup and a death subgroup according to the survival outcome. The data were processed using univariate analysis and multivariate logistic regression analysis.

RESULTS

Compared with the control group, the IM group had higher levels of white blood cell count, lymphocyte count, CD3⁺, CD4⁺, CD8⁺, CD4⁺CD25⁺, DR⁺CD8⁺, CD38⁺CD8⁺, effector-memory CD4⁺CD62L^-CD45RO⁺ and effector-memory CD8⁺CD62L^-CD45RO⁺, but lower levels of NK cells, B cells, CD4⁺CD28⁺, CD8⁺CD28⁺, naive CD4⁺CD62L⁺CD45RA⁺ and naive CD8⁺CD62L⁺CD45RA⁺ (all P<0.05). Compared with the control group, the CAEBV group had lower levels of white blood cell count, lymphocyte count, CD3⁺, CD4⁺, CD8⁺, NK cells, B cells, CD4⁺CD28⁺, CD8⁺CD28⁺, naive CD4⁺CD62L⁺CD45RA⁺ and naive CD8⁺CD62L⁺CD45RA⁺, but higher levels of CD4⁺CD25⁺, DR⁺CD8⁺, CD38⁺CD8⁺, effector-memory CD4⁺CD62L^-CD45RO⁺ and effector-memory CD8⁺CD62L^-CD45RO⁺ (all P<0.05). Univariate analysis and multivariate logistic regression analysis showed that EBV DNA>105 copies/mL, platelet count <50×10¹²/L, albumin <30 g/L and serum ferritin >5000 μg/L were independent risk factors for the death of patients with CAEBV.

CONCLUSION

Patients infected with CAEBV showed imbalance of lymphocyte subsets and immune dysfunction. EBV DNA>105 copies/mL, platelet count <50×10¹²/L, albumin <30 g/L and serum ferritin >5000 μg/L are risk factors of death in patients with CAEBV.

Efficacy of allogeneic hematopoietic stem cell transplantation with cocktail conditioning regimen for the treatment of pediatric patients with chronic active Epstein-Barr virus: A retrospective observational study

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) was considered as an only therapeutic strategy for chronic active Epstein-Barr virus (CAEBV) infection with few exceptions, while efficacy of various allo-HSCT conditioning regimens for CAEBV has not been fully investigated yet. This study aimed to compare the effectiveness of cocktail conditioning regimen (CCR)-allo-HSCT with reduced-intensity conditioning regimen (RICR)-allo-HSCT for pediatric patients with CAEBV. Data of a total of 54 children with CAEBV from July 2015 to December 2020, were retrospectively analyzed. Among them, 32 patients received VP16, total body irradiation (TBI), busulfan, fludarabine, cyclophosphamide, and anti-thymocyte globulin (ATG) (CCR1 group), 10 patients received VP16, ara-C, TBI, busulfan, fludarabine, cyclophosphamide, and ATG (CCR2 group), and the remaining 12 patients received VP16, busulfan or melphalan, fludarabine, and ATG with or without ara-C (RICR group). The overall survival (OS), hematopoietic engraftment, the incidence of severe graft-versus-host disease (GVHD), and other parameters were analyzed. After adjusting for potential confounders, CCR1 (hazard ratio (HR): 0.023; 95% confidence interval (CI): 0.001-0.448; P=0.013) and CCR2 (HR: 0.028; 95%CI: 0.002-0.457; P=0.012) were associated with a longer OS than RICR. The use of CCR could markedly improve the engraftment success rate and OS rate compared with RICR for pediatric patients with CAEBV.

Clinical Features and Prognostic Factors of Children with Chronic Active Epstein-Barr Virus Infection: A Retrospective Analysis of a Single Center

OBJECTIVE

To analyze the clinical characteristics, prognosis factors and risk factors of chronic active Epstein-Barr virus infection in children.

STUDY DESIGN

Observational analysis of baseline data and follow-up evaluation data of children with chronic active Epstein-Barr virus infection in our center between January 1, 2016 and December 31, 2019; they were followed through June 30, 2020.

RESULTS

There were 96 children with chronic active Epstein-Barr virus infection (50 male and 46 female children), with the median age of 6.7 years (range from 0.6 to 17.6 years) at diagnosis. The median follow-up time was 16.5 months. The 3 most common clinical manifestations were fever, lymph node enlargement, and hepatomegaly or splenomegaly. Thirty-three patients (36.3%) also had a diagnosis of hemophagocytic lymphohistiocytosis (HLH). Epstein-Barr virus infected only T lymphocytes, natural killer cells, or both T- and natural killer-cell types in 15 (33.3%), 17 (37.8%), and 13 (28.9%), respectively. At the end of follow-up, 26 children had died, 60 survived, and 10 were lost to follow-up. Generally, progression-free survival was 69.8% ± 2.4%. The level of interleukin (IL)-6 and IL-10 and the combination of younger age and lower pathologic grade at diagnosis were independent prognostic factors by Cox regression analysis (P = .009 and .018, respectively).

CONCLUSIONS

Children with lower levels of IL-6 and IL-10, or with younger age and lower pathologic grades, generally had favorable outcomes at the terminal point of follow-up, indicating better prognostic signs.

Ruxolitinib in Patients With Chronic Active Epstein-Barr Virus Infection: A Retrospective, Single-Center Study

Background: Chronic active Epstein-Barr virus (CAEBV) infection is one of the EBV-positive T- or NK-cell lymphoproliferative diseases. There is no safe and effective treatment currently and the only proven curable therapy is allogeneic hematopoietic stem cell transplantation (allo-HSCT). The JAK1/2 inhibitor, ruxolitinib, is now considered a novel therapy in inflammatory disease, and hypercytokinemia is an important feature of CAEBV.

Method: All patients who suffered active CAEBV and were treated with ruxolitinib as compassionate use in our center from Sep 1, 2017, and Apr 30, 2019, were retrospectively analyzed.

Results: In general, seven out of nine patients responded to ruxolitinib. Six out of seven patients became afebrile within 48 h. The AST/ALT level of three out of four patients decreased after ruxolitinib treatment. Two patients with cytopenia recovered. No significant decrease in the EBV-DNA copy number was observed (p = 0.161). For those seven patients who responded to ruxolitinib, the median continuing period in remission was 7.1 weeks (range, 3.4–101.0 weeks). Two patients achieved long-term stable remission with ruxolitinib monotherapy. None of these patients discontinued ruxolitinib due to the possible toxicity.

Conclusion: Ruxolitinib is an effective and rather safe option for controlling the inflammatory symptoms of active CAEBV, especially in patients with CAEBV who have failed previous treatments or have relapsed. It can also play a promising role in improving the quality of daily life of patients and successfully bridging to allo-HSCT.

Chronic active Epstein-Barr virus infection treated with PEG-aspargase: A case report

BACKGROUND

Chronic active Epstein-Barr virus infection (EBV) is a systemic EBV-positive lymphoproliferative disease, which may lead to fatal illness. There is currently no standard treatment regimen for chronic active EBV (CAEBV), and hematopoietic stem cell transplantation is the only effective treatment. We here report a CAEBV patient treated with PEG-aspargase, who achieved negative EBV-DNA.

CASE SUMMARY

A 33-year-old female Chinese patient who had fever for approximately 3 mo was admitted to our hospital in December 2017. EBV-DNA was positive with a high copy number. She was diagnosed with chronic active EB virus infection. PEG-aspargase was administered at a dose of 1500 U/m² at a 14-d interval, resulting in eradication of EBV for more than 6 mo. The effect of PEG-aspargase in this patient was excellent.

CONCLUSION

A chemotherapy regimen containing PEG-aspargase for CAEBV may be further considered.

Two cases of pregnancy after achieving complete remission of chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus (CAEBV) infection characterized by persistent infectious mononucleosis-like symptoms can lead to cardiovascular diseases. We encountered two pregnant women with CAEBV histories complicated with cardiovascular diseases. A 36-year-old woman with a history of myocardial infarction due to CAEBV and coronary artery bypass grafting became pregnant. Her left ventricular ejection fraction (LVEF) decreased, and cesarean section was performed at 36 weeks of gestation. Her LVEF recovered after delivery. A 32-year-old woman with a history of CAEBV and chronic hypertension was diagnosed with mild pulmonary arterial hypertension (PAH) after conception. She strongly desired to continue the pregnancy. She became complicated with severe superimposed preeclampsia at 31 weeks of gestation, and cesarean section was performed. Her PAH did not deteriorate during pregnancy or the postpartum period. Women treated for CAEBV, even with complete remission, require a preconception evaluation focused on the cardiovascular system and careful management of their pregnancy.

Surgical management of unilateral oophorectomy for ovarian tissue cryopreservation in high-risk children and adolescents with varied backgrounds

PURPOSE

Fertility preservation (FP) for children is still challenging due to an information gap. In particular, there is little information about the surgical aspects of ovarian tissue cryopreservation (OTC) for children. In the present study, the appropriateness of preoperative management and the criteria of our cases were investigated with the aim of establishing a safe OTC procedure.

METHODS

A total of 25 girls who underwent OTC from November 2015 through May 2020 were retrospectively analyzed with IRB approval.

RESULTS

The median age of the patients was 13 (1-17) years. The medical indications were varied (e.g., leukemia, lymphoma, brain tumor), and included rare diseases. Seventeen cases (68%) underwent OTC during chemotherapy or radiotherapy, and 21 (84%) had comorbidities. All cases underwent ovarian tissue retrieval (OTR) with laparoscopy, and the median operating time was 64 (36-97) min, with little bleeding. Although two had complications, all patients started treatment on schedule. The median WBC and CRP increases a day after OTR were 0 (- 4400 to + 5200)/µl and 0.21 (- 0.2 to 0.87) mg/dl, respectively, with no complications.

CONCLUSION

As long as the preoperative criteria are met, OTC could be possible even for children with a severe blood condition. In such cases, the degrees of the WBC and CRP elevations are useful to assess surgical infection.

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.

Outcome of L-DEP regimen for treatment of pediatric chronic active Epstein-Barr virus infection

Purpose

We intended to investigate the clinical features of paediatric patients with chronic active Epstein–Barr virus infection (CAEBV) and to examine the effectiveness of the L-DEP regimen before haematopoietic stem cell transplantation (HSCT).

Methods

A retrospective analysis was performed on 35 patients with CAEBV at Beijing Children’s Hospital from January 2016 to January 2020. The efficacy and adverse events of the L-DEP regimen were evaluated.

Results

The median age of the 35 patients was 7.0 years old (range 2.5–17.5 years). Twenty-eight patients achieved a clinical response (80.0%, 22 in clinical CR, 6 in clinical PR) after L-DEP. In terms of virological response, 7 patients (20%) were assessed as having virological CR, and 23 patients (65.7%) had virological PR. Finally, 29 patients underwent allo-HSCT. The median survival time was 18 months (2–50 months). The 3-year overall survival rates in patients treated with chemotherapy only (n = 6) and chemotherapy followed by HSCT (n = 25) were 33.3% and 75.4%, respectively. After L-DEP 1st treatment and L-DEP 2nd treatment, the EBV-DNA loads in blood and plasma were significantly reduced compared with those before chemotherapy (median: 4.29 × 10⁵ copies/ml vs. 1.84 × 10⁶ copies/ml, Mann–Whitney U: P = 0.0004; 5.00 × 10² copies/ml vs. 3.17 × 10³ copies/ml, Mann–Whitney U; P = 0.003; 2.27 × 10⁵ copies/ml vs. 1.84 × 10⁶ copies/ml, P = 0.0001; 5.00 × 10² copies/ml vs. 3.17 × 10³ copies/ml, P = 0.003). Compared with the liver and spleen size before chemotherapy, the size of the liver and spleen shrank significantly after L-DEP 2nd (median 3.8 cm vs. 1.9 cm, P = 0.003; 3.8 cm vs. 0 cm, P < 0.008). In addition, after L-DEP treatment, there was no difference in the clinical or virological response rate regardless of HLH status (clinical response: 77.3% vs. 84.6%, P = 0.689; virological response: 90.9% vs. 76.9%, P = 0.337).

Conclusion

The L-DEP regimen is an effective therapy in CAEBV for bridging to allo-HSCT.

Antineoplastic and anti-inflammatory effects of bortezomib on systemic chronic active EBV infection

Systemic chronic active Epstein-Barr virus (EBV; sCAEBV) infection, T- and natural killer (NK)-cell type (sCAEBV), is a fatal disorder accompanied by persisting inflammation harboring clonal proliferation of EBV-infected T or NK cells. Today's chemotherapy is insufficient to resolve disease activity and to rid infected cells of sCAEBV. The currently established treatment strategy for eradicating infected cells is allogeneic hematopoietic stem cell transplantation. In this study, we focused on the effects of proteasome inhibitor bortezomib on the disease. Bortezomib suppressed survival and induced apoptosis of EBV+ T- or NK-cell lines and peripheral mononuclear cells containing EBV-infected T or NK cells of sCAEBV patients. Bortezomib enhanced binding immunoglobulin protein/78-kDa glucose-regulated protein (Bip/GRP78) expression induced by endoplasmic reticulum stress and activated apoptosis-promoting molecules JNK and p38 in the cell lines. Bortezomib suppressed the activation of survival-promoting molecule NF-κB, which was constitutively activated in EBV+ T- or NK-cell lines. Furthermore, quantitative reverse transcription-polymerase chain reaction demonstrated that bortezomib suppressed messenger RNA expression of proinflammatory cytokines tumor necrosis factor α (TNF-α) and interferon γ (IFN-γ) in EBV+ T or NK cells from the patients. Finally, we examined the effects of bortezomib using xenograft models of sCAEBV generated by IV injection of patients' cells. The intraperitoneal administration of bortezomib significantly reduced EBV-DNA load in peripheral blood and the infiltration of EBV-infected cells in the models' livers. Moreover, the serum concentration of TNF-α and IFN-γ decreased after bortezomib treatment to the models. Our findings will be translated into the treatment of sCAEBV not only to reduce the number of tumor cells but also to suppress inflammation.

Virus-Driven Carcinogenesis

Cancer arises from the accumulation of genetic and epigenetic alterations. Even in the era of precision oncology, carcinogens contributing to neoplastic process are still an important focus of research. Comprehensive genomic analyses have revealed various combinations of base substitutions, referred to as the mutational signatures, in cancer. Each mutational signature is believed to arise from specific DNA damage and repair processes, including carcinogens. However, as a type of carcinogen, tumor viruses increase the cancer risk by alternative mechanisms, including insertional mutagenesis, viral oncogenes, and immunosuppression. In this review, we summarize virus-driven carcinogenesis to provide a framework for the control of malignant cell proliferation. We first provide a brief overview of oncogenic viruses and describe their implication in virus-related tumors. Next, we describe tumor viruses (HPV, Human papilloma virus; HBV, Hepatitis B virus; HCV, Hepatitis C virus; EBV, Epstein-Barr virus; Kaposi sarcoma herpesvirus; MCV, Merkel cell polyoma virus; HTLV-1, Human T-cell lymphotropic virus, type-1) and tumor virus-related cancers. Lastly, we introduce emerging tumor virus candidates, human cytomegalovirus (CMV), human herpesvirus-6 (HHV-6) and adeno-associated virus-2 (AAV-2). We expect this review to be a hub in a complex network of data for virus-associated carcinogenesis.

[EBV and immunodeficiency]

Epstein-Barr virus (EBV), discovered in 1964, is a double-stranded DNA virus belonging to the Herpesviridae family. EBV has a lymphoid tropism with transforming capacities using different oncogenic viral proteins. This virus has two replication cycles: a lytic cycle mainly occuring during primary infection and a latent cycle allowing viral persistence into host memory B cells. More than 90% of adults are seropositive for EBV worldwide, with a past history of asymptomatic or mild primary infection. EBV infection can sometimes cause life-threatening complications such as hemophagocytic lymphohistiocytosis, and lead to the development of lymphoproliferative disorders or cancers. Risk factors associated with these phenotypes have been recently described through the study of monogenic primary immune deficiencies with EBV susceptibility. We here review the virological and immunological aspects of EBV infection and EBV-related complications with an overview of current available treatments.

Rapid identification and characterization of infected cells in blood during chronic active Epstein-Barr virus infection

Epstein-Barr virus (EBV) preferentially infects epithelial cells and B lymphocytes and sometimes T and NK lymphocytes. Persistence of EBV-infected cells results in severe lymphoproliferative disorders (LPDs). Diagnosis of EBV-driven T or NK cell LPD and chronic active EBV diseases (CAEBV) is difficult, often requiring biopsies. Herein, we report a flow-FISH cytometry assay that detects cells expressing EBV-encoded small RNAs (EBERs), allowing rapid identification of EBV-infected cells among PBMCs. EBV-infected B, T, and/or NK cells were detectable in various LPD conditions. Diagnosis of CAEBV in 22 patients of Caucasian and African origins was established. All exhibited circulating EBV-infected T and/or NK cells, highlighting that CAEBV is not restricted to native American and Asian populations. Proportions of EBV-infected cells correlated with blood EBV loads. We showed that EBV-infected T cells had an effector memory activated phenotype, whereas EBV-infected B cells expressed plasma cell differentiation markers. Thus, this method achieves accurate and unambiguous diagnoses of different forms of EBV-driven LPD and represents a powerful tool to study their pathophysiological mechanisms.

Clinical analysis of chronic active EBV infection with coronary artery dilatation and a matched case-control study

OBJECTIVE

To investigate the clinical characteristics, treatment, prognosis and risk factors for chronic active Epstein-Barr Virus infection (CAEBV) associated with coronary artery dilatation (CAD) in children.

METHODS

Children with CAEBV associated with CAD hospitalized at Beijing Children's Hospital, Capital Medical University from March 2016 to December 2019 were analyzed. Children with CAEBV without CAD were selected as the control group and matched by sex, age, treatment and admission time. The clinical manifestations, laboratory and ultrasound examinations, treatment and prognosis of the children were collected in both groups.

RESULTS

There were 10 children with CAEBV combined with CAD, including 6 males and 4 females, accounting for 8.9% (10/112) of CAEBV patients in the same period, with an onset age of 6.05 (2.8-14.3) years. The median follow-up time was 20 (6-48) months. All the patients had high copies of EBV-DNA in whole blood [1.18 × 10⁷ (1.90 × 10⁵-3.96 × 10⁷) copies/mL] and plasma [1.81 × 10⁴ (1.54 × 10³-1.76 × 10⁶) copies/mL], and all biopsy samples (bone marrow, lymph nodes or liver) were all positive for Epstein-Barr virus-encoded small RNA. Among the 10 children, 8 had bilateral CAD, and 2 patients had unilateral CAD. After diagnosis, 7 children were treated with L-DEP chemotherapy in our hospital. After chemotherapy, four patients underwent allogeneic hematopoietic stem cell transplantation (HSCT). The others were waiting for HSCT. At the time of the last patients follow up record, the CAD had returned to normal in 3 patients, and the time from the diagnosis of CAD to recovery was 21 (18-68) days. LDH, serum ferritin, TNF-α and IL-10 levels were statistically significantly different between the two groups (P = 0.009, 0.008, 0.026 and 0.030). There were no significant differences in survival rate between the two groups (P = 0.416).

CONCLUSION

The incidence of CAEBV with CAD was low. CAEBV with CAD did not influence the prognosis. Patients who had high LDH, serum ferritin, TNF-α, and IL-10 levels early in their illness were more likely to develop CAD.

Chronic Active Epstein-Barr Virus Infection: The Elucidation of the Pathophysiology and the Development of Therapeutic Methods

Chronic active Epstein-Barr virus infection (CAEBV) is a disease where Epstein-Barr virus (EBV)-infected T- or NK-cells are activated and proliferate clonally. The symptoms of this dual-faced disease include systemic inflammation and multiple organ failures caused by the invasion of infected cells: inflammation and neoplasm. At present, the only effective treatment strategy to eradicate EBV-infected cells is allogeneic stem cell transplantation. Lately, the investigation into the disease's pathogenic mechanism and pathophysiology has been advancing. In this review, I will evaluate the new definition in the 2017 WHO classification, present the advancements in the study of CAEBV, and unfold the future direction.

Chronic active EBV infection in refractory enteritis with longitudinal ulcers with a cobblestone appearance: an autopsied case report

Background

Chronic active Epstein–Barr virus infection (CAEBV) is defined as Epstein–Barr virus (EBV)-positive T/NK cell-related neoplasia, and its major clinical symptom is systemic inflammation presenting as infectious mononucleocytosis, whereas enteritis and diarrhea are minor clinical symptoms. The complex mixture of tumorigenic processes of EBV-positive cells and physical symptoms of systemic inflammatory disease constitutes the varied phenotypes of CAEBV. Herein, we describe a case of CAEBV that was initially diagnosed as Crohn’s disease (CD) based on ileal ulcers and clinical symptoms of enteritis.

Case presentation

A 19-year-old woman complained of abdominal pain and fever. Blood examination showed normal blood cell counts without atypical lymphocyte but detected modest inflammation, hypoalbuminemia, slight liver dysfunction, and evidence of past EBV infection. The esophagogastroduodenoscopic findings were normal. However, colonoscopy revealed a few small ulcers in the terminal ileum. The jejunum and ileum also exhibited various forms of ulcers, exhibiting a cobblestone appearance, on capsule endoscopy. Based on these clinical findings, she was strongly suspected with CD. In the course of treatment by steroid and biologics for refractory enteritis, skin ulcers appeared about 50 months after her initial hospital visit. Immunohistology of her skin biopsy revealed proliferation of EBV-encoded small RNA (EBER)-positive atypical lymphocytes. We retrospectively assessed her previous ileal ulcer biopsy before treatment and found many EBER-positive lymphocytes. Blood EBV DNA was also positive. Therefore, she was diagnosed with extranodal NK/T-cell lymphoma with CAEBV-related enteritis rather than CD. She was treated with cyclosporine and prednisolone combination therapy for CAEBV-related systemic inflammation and chemotherapy for malignant lymphoma. Unfortunately, her disease continued to progress, leading to multiple organ failure and death at the age of 23 years.

Conclusion

Clinicians need to remember the possibility of CAEBV as a differential diagnosis of refractory enteritis. Enteritis with intestinal ulcer is a rare symptom of CAEBV, and it is impossible to acquire a definitive diagnosis by ulcer morphology only. In cases where the possibility of CAEBV remains, tissue EBVR expression should be checked by in situ hybridization and blood EBV DNA.

Chronic active Epstein-Barr virus infection: A heterogeneous entity requiring a high index of suspicion for diagnosis

Chronic active Epstein-Barr virus infection of T- and NK-cell type, systemic form, is a rare entity within the spectrum of EBV-driven T- and NK-cell lymphoproliferative disorders. Established diagnostic criteria and a characteristic clinical course help to differentiate it from other closely related EBV-positive neoplasms and clinical states. We present a patient and review the natural history, pathologic features, pathogenesis, and differential diagnosis of this entity.

Case Report: Autoimmune Lymphoproliferative Syndrome vs. Chronic Active Epstein-Barr Virus Infection in Children: A Diagnostic Challenge

Autoimmune lymphoproliferative syndrome (ALPS) is a disorder characterized by a disruption of the lymphocyte apoptosis pathway, self-tolerance, and immune system homeostasis. Defects in genes within the first apoptosis signal (FAS)-mediated pathway cause an expansion of autoreactive double-negative T cells leading to non-malignant lymphoproliferation, autoimmune disorders, and an increased risk of lymphoma. The aim of the study was to show the diagnostic dilemmas and difficulties in the process of recognizing ALPS in the light of chronic active Epstein-Barr virus (CAEBV) infection. Clinical, immunological, flow cytometric, biomarkers, and molecular genetic approaches of a pediatric patient diagnosed with FAS-ALPS and CAEBV are presented. With the ever-expanding spectrum of molecular pathways associated with autoimmune lymphoproliferative disorders, multiple genetic defects of FAS-mediated apoptosis, primary immunodeficiencies with immune dysregulation, malignant and autoimmune disorders, and infections are included in the differential diagnosis. Further studies are needed to address the issue of the inflammatory and neoplastic role of CAEBV as a triggering and disease-modifying factor in ALPS.

Reactivation of the Epstein-Barr Virus Leading to Acute Liver Failure in a Patient Living with HIV

We report a case of a 46-year-old female living with HIV since 2010 who was originally from Malawi and had settled in the UK in 2001. She was admitted to our hospital with confusion and quickly noted to have a decreased Glasgow Coma Scale of 10/15. Her biochemical parameters showed the presence of elevated liver function tests (LFTs), clotting abnormalities, and her ammonia were found to be >400 mmol/L with a severe metabolic acidosis (pH = 7.05). She was treated for HIV with combined antiretroviral therapy, namely tenofovir disoproxil fumarate, emtricitabine (FTC) and cobicistat boosted atazanavir 2 years previously and had normal LFTs at that time. Her HIV-1 viral load was 1400 copies/ml on admission after recently having an undetectable viral load 2 months previously, and her CD4 count was 480. Her relevant past medical history included insulin-dependent diabetes mellitus. Her other medications included insulin, ramipril, sertraline, amitriptyline, and zopiclone. Toxicology and viral hepatitis screen were negative. Epstein Barr virus (EBV) serology showed evidence of previous exposure, but she was found to have a very high EBV viral load of 55,000 copies/ml, which given her serology, was very likely to be a reactivation of EBV infection rather than a primary EBV infection. In the intensive care unit, the patient deteriorated and died very quickly. The postmortem examination showed extensive hepatic necrosis with collapse. To our knowledge, this is the first case report to show an association between EBV reactivation and fulminant hepatic failure in an individual living with HIV.

Impact of melphalan dose during reduced-intensity conditioning on engraftment of cord blood transplantation for chronic Epstein-Barr virus-associated T or NK cell lymphoproliferative diseases

The rejection rate in cord blood transplants for chronic Epstein-Bar virus-associated T or natural killer cell lymphoproliferative diseases using our standard reduced-intensity conditioning "LPAM140 regimen," which includes fludarabine, melphalan (LPAM), etoposide, and antithymocyte globulin, has been high. To ensure better engraftment, we increased the LPAM dose to 210 mg/m² ("LPAM210 regimen"). Patient data (n = 22; LPAM140, n = 7; LPAM210, n = 15) were analyzed retrospectively. The engraftment rate after the LPAM210 regimen (100.0%) was significantly higher than that after the LPAM140 regimen (57.1%; P = .002). Fludarabine combined with melphalan (210 mg/m² ) had a favorable impact on engraftment.

Adult-onset Still's disease in a 73-year-old Maltese man

Adult-onset Still's disease (AOSD) is a rare autoinflammatory condition diagnosed by Yamaguchi criteria. We report an atypical presentation of a 73-year-old man, who was admitted with fever, sore throat and pleurisy that were unresponsive to three courses of antibiotics. Fever persisted in a quotidian pattern and the typical salmon-coloured rash consistent with AOSD appeared at 4 weeks from symptoms onset. These features in addition to neutrophilia and hyperferritinaemia in the absence of concurrent infectious and neoplastic causes satisfied Yamaguchi criteria for a diagnosis of AOSD. Epstein-Barr antigen was initially detected at moderate titre levels, but was undetectable after 1 week. Complete resolution of symptoms was reported on initiation of steroid treatment. A relationship between disease onset and viral syndromes has been documented to occur and few similar cases preceded by Epstein-Barr virus detection have been reported.

Diagnostic dilemmas in Epstein-Barr virus hepatitis mimicking autoimmune hepatitis: A case report

We report a case of 55-year-old female with chief complaints of fever and deranged liver function tests, diagnosed as autoimmune hepatitis (AIH) and under immunosuppressive therapy for two years. Following the failure in clinical improvement, she was started on anti-tubercular therapy (ATT). While investigating the underlying etiology, virological markers for Hepatitis A to E were found to be negative with plasma Epstein-Barr virus (EBV) viral load of 5 log₁₀ copies/ml. Additional investigation of the liver biopsy showed Hodgkin's lymphoma (HL). The patient was initiated on chemotherapy but eventually succumbed to the illness. This case report underlines the dilemma in the initial diagnosis of AIH and the importance of considering hepatic involvement of EBV as one of the differential diagnosis among clinically suspected AIH cases not responding to immunosuppressive medications.

Natural killer/T-cell lymphoma with intracranial infiltration and Epstein-Barr virus infection: A case report

BACKGROUND

Because of atypical clinical symptoms, lymphoma is easily confused with infectious diseases. Extranodal nasal-type natural killer/T-cell lymphoma (NKTL) is more common, and there are few cases of eyelid site onset and intracranial infiltration, which increases the difficulty of diagnosis. This disease usually has a very poor prognosis and there are few reports of recovery.

CASE SUMMARY

A 3-year-old boy was admitted to our hospital due to an initial misdiagnosis of "eyelid cellulitis" and failed antibiotic treatment. He was characterized by fever, right eyeball bulging, convulsions, and abnormal liver function. His blood Epstein-Barr virus (EBV) DNA was positive (8.798 × 10⁴ copies/mL), and remained positive for about half a year. The cranial imaging examination suggested a space-occupying lesion in the right eyelid, with the right temporal lobe and meninges involved. The boy underwent ocular mass resection. The pathological diagnosis was NKTL. He was diagnosed as having NKTL with intracranial infiltration, combined with chronic active EBV infection (CAEBV). Then he underwent systemic chemotherapy and intrathecal injection. The boy suffered from abnormal blood coagulation, oral mucositis, diarrhea, liver damage, and severe bone marrow suppression but survived. Finally, the tumor was completely relieved and his blood EBV-DNA level turned negative. The current follow-up has been more than 2 years and his condition is stable.

CONCLUSION

This case suggests that chemotherapy combined with intrathecal injection may have a good effect on intracranial infiltrating lymphoma and CAEBV, which deserves further study and discussion.

Hydroa vacciniforme-like lymphoproliferative disorder: A study of clinicopathology and whole-exome sequencing in Chinese patients

BACKGROUND

Hydroa vacciniforme-like lymphoproliferative disorder (HVLPD) encompasses a rare group of Epstein-Barr virus (EBV)-associated lymphoproliferative diseases.

OBJECTIVE

To define the clinical and pathologic characteristics of HVLPD and to identify mutant genes that may be related to the development of HVLPD.

METHODS

Clinical data and archived formalin-fixed, paraffin-embedded tissue were obtained from 19 patients. Specimens were analyzed by immunohistochemistry and in situ hybridization to detect EBV-encoded RNA (EBER1/2) and for T cell receptor (TCR) gene rearrangements. Whole-exome sequencing (WES) analysis was also performed in this study.

RESULTS

Thirteen patients survived between 3-58 months (median, 21 months) during the follow-up. Six patients who were almost adults (>15 years old) and died of the disease presented with facial edema. Lactate dehydrogenase (LDH) levels were elevated, and the TCR gene rearrangement test was positive more frequently in the patients who died. Compared with Chinese patients in a similar previous report, our patients had significantly higher proliferation (in all cases, the Ki-67 index was greater than 10 %) and a more aggressive clinical course. Moreover, after WES and Sanger verification, STAT3, IKBKB, ELF3, CHD7, KMT2D, ELK1, RARB and HPGDS were screened out in our patients.

CONCLUSIONS

HVLPD refers to a heterogeneous group of cutaneous lymphoproliferative diseases with different clinical and pathological features that affect patient outcomes. Gene mutations may be correlated with the development of HVLPD, and our study may provide new therapeutic targets for HVLPD.