Chronic Active Epstein-Barr Virus Infection: Is It Immunodeficiency, Malignancy, or Both?

Role of rapidly evolving immunotherapy in chronic active Epstein-Barr virus disease

Chronic active Epstein-Barr Virus disease is a kind of Epstein-Barr Virus associated T/NK cell lymphoproliferative disease. At present, there is still a lack of standard therapeutic regimen for its treatment, but its basic treatment principles include controlling inflammatory response, anti-tumor proliferation, and immune reconstitution. Hematopoietic stem cell transplantation is currently the only method that can cure this disease. In recent years, immunotherapy has developed rapidly and is widely used in the treatment of various hematological malignancies; various immunotherapy drugs, including PD-1 inhibitors, have also demonstrated their safety and efficacy in CAEBV, while immune cell therapies such as Epstein- Barr virus-specific T cells have also displayed their unique advantages in CAEBV.

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.

What Makes It Tick: Exploring the Mechanisms of Post-treatment Lyme Disease Syndrome

Post-treatment Lyme disease syndrome (PTLDS), which may also be referred to incorrectly as "chronic Lyme disease," is defined by the Infectious Diseases Society of America (IDSA) as the presence of fatigue, pain, and/or cognitive complaints with the functional impact that persists for more than six months after completing treatment for Lyme disease (LD). These symptoms occur in 10%-20% of patients previously diagnosed with LD caused by the bacteria Borrelia burgdorferi and appropriately treated with a course of antibiotics. The symptoms of PTLDS can be easily overlooked or misdiagnosed as a psychiatric manifestation in geographic locations that rarely see LD. In contrast, geographic locations with a higher prevalence of LD may be more aware of PTLDS symptoms and have higher clinical suspicion leading to this diagnosis. The pathophysiology behind the persistent symptoms some people experience from a primary infection is still largely unknown. Some mechanisms that have been proposed include permanent tissue damage and inflammation, immune system dysfunction, autoimmune response, co-infection, and even persistent infection refractory to treatment. We propose that ongoing PTLDS symptoms seem to be related to an autoimmune response to the tissue damage and inflammation caused by the viable or nonviable spirochete pathogen. At this point, PTLDS is diagnosed clinically as no quantifiable methods are available from laboratory or tissue diagnostics as of 2024. Similar pathophysiological features of PTLDS are seen in diseases such as COVID-19 or chronic fatigue syndrome (CFS). More effective diagnostic approaches might include further studies looking at a possible connection in the genomes of individuals developing PTLDS, quantifiable biomarkers, common inflammatory markers/pathways, and careful histopathological studies of human tissues.

DRB1 locus alleles of HLA class II are associated with modulation of the immune response in different serological profiles of HIV-1/Epstein-Barr virus coinfection in the Brazilian Amazon region

Background

Epstein-Barr virus (EBV) infection involves distinct clinical and serological profiles. We evaluated the frequency of alleles of locus DRB1 of HLA class II in different serological profiles of EBV infection among HIV-1 infected patients.

Methods

We recruited 19 patients with primary infection, 90 with serological transition and 467 with past infection by EBV, HIV-1 co-infection was 100% in primary infection and approximately 70% in other serological profiles. EBV viral load was quantified by real-time PCR, T lymphocyte quantification and cytokine level analysis were performed by flow cytometry, and HLA locus genotyping was performed by PCR-SSO.

Results

The DRB1*09 allele was associated with primary infection (p: 0.0477), and carriers of the allele showed changes in EBV viral load (p: 0.0485), CD8(+) T lymphocyte counts (p: 0.0206), double-positive T lymphocyte counts (p: 0.0093), IL-4 levels (p: 0.0464) and TNF levels (p: 0.0161). This allele was also frequent in HIV-coinfected individuals (p: 0.0023) and was related to the log10 HIV viral load (p: 0.0176) and CD8(+) T lymphocyte count (p: 0.0285). In primary infection, the log10 HIV viral load was high (p: 0.0060) and directly proportional to the EBV viral load (p: 0.0412). The DRB1*03 allele correlated with serological transition (p: 0.0477), EBV viral load (p: 0.0015), CD4(+) T lymphocyte count (p: 0.0112), CD8(+) T lymphocyte count (p: 0.0260), double-negative T lymphocyte count (p: 0.0540), IL-4 levels (p: 0.0478) and IL-6 levels (p: 0.0175). In the serological transition group, the log10 HIV viral load was high (p: 0.0060), but it was not associated with the EBV viral load (p: 0.1214). Past infection was related to the DRB1*16 allele (p: 0.0477), with carriers displaying IgG levels (p: 0.0020), CD4(+) T lymphocyte counts (p: 0.0116) and suggestive CD8(+) T count alterations (p: 0.0602). The DRB01*16 allele was also common in HIV-1 patients with past EBV infection (p: 0.0192); however, the allele was not associated with clinical markers of HIV-1 infection.

Conclusion

Our results suggest that HLA class II alleles may be associated with the modulation of the serological profiles of the immune response to Epstein-Barr virus infection in patients coinfected with HIV-1.

Chronic active Epstein-Barr virus disease originates from infected hematopoietic stem cells

ABSTRACT

Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a lethal syndrome because of persistent EBV infection. When diagnosed as CAEBV, EBV infection was observed in multiple hematopoietic lineages, but the etiology of CAEBV is still elusive. Bone marrow and peripheral cells derived from 5 patients with CAEBV, 1 patient with EBV-associated hemophagocytic lymphohistiocytosis, and 2 healthy controls were analyzed. Multiple assays were applied to identify and characterize EBV-infected cells, including quantitative polymerase chain reaction, PrimeFlow, and single-cell RNA-sequencing (scRNA-seq). Based on scRNA-seq data, alterations in gene expression of particular cell types were analyzed between patients with CAEBV and controls, and between infected and uninfected cells. One patient with CAEBV was treated with allogeneic hematopoietic stem cell transplantation (HSCT), and the samples derived from this patient were analyzed again 6 months after HSCT. EBV infected the full spectrum of the hematopoietic system including both lymphoid and myeloid lineages, as well as the hematopoietic stem cells (HSCs) of the patients with CAEBV. EBV-infected HSCs exhibited a higher differentiation rate toward downstream lineages, and the EBV infection had an impact on both the innate and adaptive immunity, resulting in inflammatory symptoms. EBV-infected cells were thoroughly removed from the hematopoietic system after HSCT. Taken together, multiple lines of evidence presented in this study suggest that CAEBV disease originates from the infected HSCs, which might potentially lead to innovative therapy strategies for CAEBV.

Exploring the Significance of Immune Checkpoints and EBV Reactivation in Antibody Deficiencies with Near-Normal Immunoglobulin Levels or Hyperimmunoglobulinemia

This study delves into the intricate landscape of primary immunodeficiencies, with a particular focus on antibody deficiencies characterized by near-normal immunoglobulin levels or hyperimmunoglobulinemia. Contrary to the conventional focus on genetic dysregulation, these studies investigate the key roles of immune checkpoints, such as PD-1/PD-L1, CTLA-4/CD86, and CD200R/CD200, on selected subpopulations of T and B lymphocytes and their serum concentrations of soluble forms in patients recruited for the studies in healthy volunteers. In addition, the studies also show the role of Epstein-Barr virus (EBV) reactivation and interactions with tested pathways of immune checkpoints involved in the immunopathogenesis of this disease. By examining the context of antibody deficiencies, this study sheds light on the nuanced interplay of factors beyond genetics, particularly the immune dysregulations that occur in the course of this type of disease and the potential role of EBV reactivation, which affects the clinical presentation of patients and may contribute to the development of cancer in the future, especially related to hematological malignancies.

Treatment Options for Epstein-Barr Virus-Related Disorders of the Central Nervous System

Epstein-Barr virus (EBV), a causative agent for several types of lymphomas and mucosal cancers, is a human lymphotropic herpesvirus with the capacity to establish lifelong latent infection. More than 90% of the human population worldwide is infected. The primary infection is usually asymptomatic in childhood, whereas infectious mononucleosis (IM) is common when the infection occurs in adolescence. Primary EBV infection, with or without IM, or reactivation of latent infection in immunocompromised individuals have been associated with a wide range of neurologic conditions, such as encephalitis, meningitis, acute disseminated encephalomyelitis, and cerebellitis. EBV is also involved in malignant lymphomas in the brain. An increasing number of reports on EBV-related disorders of the central nervous system (CNS) including the convincing association with multiple sclerosis (MS) have put in focus EBV-related conditions beyond its established link to malignancies. In this review, we present the clinical manifestations of EBV-related CNS-disorders, put them in the context of known EBV biology and focus on available treatment options and future therapeutic approaches.

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.

T cell-mediated immunity during Epstein-Barr virus infections in children

Epstein-Barr virus (EBV) infection is extremely common worldwide, with approximately 90% of adults testing positive for EBV antibodies. Human are susceptible to EBV infection, and primary EBV infection typically occurs early in life. EBV infection can cause infectious mononucleosis (IM) as well as some severe non-neoplastic diseases, such as chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), which can have a heavy disease burden. After primary EBV infection, individuals develop robust EBV-specific T cell immune responses, with EBV-specific CD8⁺ and part of CD4⁺ T cells functioning as cytotoxic T cells, defending against virus. Different proteins expressed during EBV's lytic replication and latent proliferation can cause varying degrees of cellular immune responses. Strong T cell immunity plays a key role in controlling infection by decreasing viral load and eliminating infected cells. However, the virus persists as latent infection in EBV healthy carriers even with robust T cell immune response. When reactivated, it undergoes lytic replication and then transmits virions to a new host. Currently, the relationship between the pathogenesis of lymphoproliferative diseases and the adaptive immune system is still not fully clarified and needs to be explored in the future. Investigating the T cell immune responses evoked by EBV and utilizing this knowledge to design promising prophylactic vaccines are urgent issues for future research due to the importance of T cell immunity.

Case report of extranodal natural killer/T-cell lymphoma that induced secondary hemophagocytic syndrome-related histiocytic glomerulopathy

Hemophagocytic syndrome (HPS) is a proliferative disease of the mononuclear macrophage system involving multiple organs and systems. We report a 50-year-old Asian woman who presented with unexplained fever and proteinuria. Laboratory tests showed cytopenia, considerably elevated serum ferritin and IL-2 receptor concentrations, and evidence of hemophagocytosis in the bone marrow. A renal biopsy showed macrophage infiltration into the glomerulus, resulting in podocyte and endothelial cell damage. We finally diagnosed the patient with extranodal natural killer/T-cell lymphoma, nasal type that induced HPS-related histiocytic glomerulopathy. Proteinuria and inflammation responded to treatment with high-dose pulsed methylprednisolone combined with VP-16 and cyclosporine. To the best of our knowledge, this is the first documented case of HPS-related histiocytic glomerulopathy triggered by a malignant tumor.

COVID-19 Associated Vasculitis Confirmed by the Tissues RT-PCR: A Case Series Report

Background: Several cases of skin and central nervous system vasculopathy associated with COVID-19 in children have been published, but the information is rather limited. Our study aimed to describe these cases of vasculitis associated with COVID-19 in children. Methods: In the retrospective-prospective case series study we included information regarding four children with COVID-19-associated vasculitis. In every case, we had a morphological description and the etiology was confirmed via real-time polymerase chain reaction during a tissue biopsy. Results: The most involved systems were skin (4/4), respiratory (3/4), cardiovascular (2/4), nervous (1/4), eye (1/4), kidney (1/4), and inner year (1/4). All patients had increased inflammatory markers and thrombotic parameters (D-dimer). No patient met the criteria for multisystem inflammatory syndrome in children. Two patients met polyarteritis nodosa criteria, one met Henoch–Schonlein purpura criteria, and one met unclassified vasculitis criteria. All patients were treated with systemic glucocorticosteroids (two-pulse therapy). Non-biologic DMARDs were prescribed in all cases; 1/4 patients (25%) was treated with intravenous immunoglobuline, and 3/4 (75%) were treated with biologics (etanercept, tocilizumab, and adalimumab). Conclusions: Vasculitis associated with COVID-19 could be a life-threatening condition; SARS-CoV-2 might be a new trigger or etiological agent for vasculitis and other immune-mediated diseases. Further research and collection of similar cases are required.

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.

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.

Epidemiology and clinical characteristics of Epstein-Barr virus infection among children in Shanghai, China, 2017-2022

Objective

To investigate the epidemiology and infectious characteristics of Epstein-Barr virus (EBV) infection among children in Shanghai, China from 2017 to 2022.

Methods

We conducted a retrospective analysis of 10,260 inpatient patients who were subjected EBV nucleic acid testing from July 2017 to December 2022. Demographic information, clinical diagnosis, laboratory findings, etc. were collected and analyzed. EBV nucleic acid testing were performed by real-time PCR.

Results

A total of 2192 (21.4%) inpatient children were EBV-positive, with the average age of 7.3 ± 0.1 y. EBV detection was stable from 2017 to 2020 (26.9~30.1%), but showed essential decreases in 2021 (16.0%) and 2022 (9.0%). EBV was highest (>30%) detected from three quarters (Q) including 2018-Q4, 2019-Q4 and 2020-Q3. There were 24.5% of EBV coinfection with other pathogens, including bacteria (16.8%), other viruses (7.1%) and fungi (0.7%). EBV viral loads increased when coinfecting with bacteria ((142.2 ± 40.1) ×10⁴/mL) or other viruses ((165.7 ± 37.4) ×10⁴/mL). CRP significantly increased in EBV/fungi coinfection, while procalcitonin (PCT) and IL-6 showed remarkable increases in EBV/bacteria coinfection. Most (58.9%) of EBV-associated diseases belonged to immune disorders. The primary EBV-related diseases were systemic lupus erythematosus (SLE, 16.1%), immunodeficiency (12.4%), infectious mononucleosis (IM, 10.7%), pneumonia (10.4%) and Henoch-schonlein purpura (HSP, 10.2%). EBV viral loads were highest ((233.7 ± 27.4) × 10⁴/mL) in patients with IM.

Conclusion

EBV was prevalent among children in China, the viral loads increased when coinfecting with bacteria or other viruses. SLE, immunodeficiency and IM were the primary EBV-related diseases.

Multisystem T-cell Chronic Active Epstein-Barr Virus Infection: From the Eye to the Kidney

Chronic active Epstein-Barr virus (CAEBV) infection is usually a fatal disease associated with clonal proliferation of EBV-infected T or NK cells. We present the case of a 33-year-old Peruvian patient who developed a multisystem CAEBV, notably responsible for exceptional ophthalmological and renal damage. We describe the clinicopathological features of EBV-induced lymphoproliferative disorder.

Pediatric inborn errors of immunity causing hemophagocytic lymphohistiocytosis: Case report and review of the literature

Inborn errors of immunity are a group of genetic disorders caused by mutations that affect the development and/or function of several compartments of the immune system, predisposing patients to infections, autoimmunity, allergy and malignancies. In this regard, mutations that affect proteins involved in trafficking, priming, docking, or membrane fusion will impair the exocytosis of lytic granules of effector NK and cytotoxic T lymphocytes. This may predispose patients to hemophagocytic lymphohistiocytosis, a life-threatening immune disorder characterized by systemic lymphocyte and macrophage activation, and increased levels of cytokines, which lead to an uncontrolled hyperinflammation state and progressive multiorgan damage. In this review, we will describe a clinical case and recent advances in inborn errors of immunity predisposing to hemophagocytic lymphohistiocytosis. Summary sentence: Review of recent advances in inborn errors of immunity predisposing to hemophagocytic lymphohistiocytosis.

The superiority of Epstein-Barr virus DNA in plasma over in peripheral blood mononuclear cells for monitoring EBV-positive NK-cell lymphoproliferative diseases

Epstein-Barr virus (EBV), characterized as an omnipresent virus, has been found able to infect NK cells and leads to NK-cell type EBV-positive lymphoproliferative diseases (EBV-NK-LPDs). We retrospective analysed 202 EBV-NK-LPDs (including 64 CAEBV-NK, 27 ANKL, and 111 ENKTL) patients' relationships between EBV DNA copies laboratory test results and clinical features. In CAEBV-NK cohort, EBV DNA loads in either plasma or PBMCs had significant differences between the active state and the inactive state. Receiver operating characteristic (ROC) curves were used to measure the diagnosis accuracy of EBV DNA copies. After comparing the area under the curve (AUC), EBV DNA loads in plasma had significantly higher accuracy in distinguishing disease activation than in PBMCs. Therefore, we propose redefining CAEBV-NK diagnosis criteria as increased EBV DNA copies in plasma (over 7.1×10² copies/ml) instead of in peripheral blood. In ANKL and ENKTL cohorts, patients who received effective therapy had significantly lower EBV DNA copies in plasma & PBMCs than in those with ineffective therapy. The significant and consistent decline indicated EBV DNA loads in plasma being a more sensitive biomarker in monitoring EBV-NK-LPDs therapy responses. Hemophagocytic lymphohistiocytosis (HLH) can occur secondary to EBV-NK-LPDs, mostly associated with a poor prognosis, so we try to estimate the combination of HLH by monitoring EBV DNA copies. When comparing the ROC curves of EBV DNA copies, EBV DNA loads in plasma had higher diagnosis accuracy. When the copies level over 4.16×10³ copies/ml, it might indicate combining with HLH. This article is protected by copyright. All rights reserved.

Epstein–Barr Virus (EBV) Genotypes Associated with the Immunopathological Profile of People Living with HIV-1: Immunological Aspects of Primary EBV Infection

Background: The aim of the present study was to evaluate the immunological profile of adult HIV-1+ patients coinfected with primary Epstein–Barr virus (EBV) infection who were free of antiretroviral drugs and inhabitants of the Brazilian Amazon region. Materials and methods: Primary EBV infection was screened by the semiquantitative detection of IgM and IgG anti-VCA. Genotypes were determined by conventional PCR. EBV and HIV viral load (VL) were quantified by real-time PCR. Cytokine dosage and cell quantification were performed by cytometry. Results: Only HIV-1+ individuals had primary EBV infection (7.12%). The EBV-1 genotype was the most prevalent (47.37%). The VL of HIV-1 was lower in the HIV/EBV-2 group. CD4+ T lymphocytes were inversely proportional to the VL of EBV in HIV/EBV-1/2 multi-infected patients. The HIV/EBV-2 group had the lowest cytokine levels, especially IFN-γ and IL-4. Different correlations were proposed for each coinfection. The late search for specific care related to HIV infection directly affected the cytokine profile and the number of CD8+ T lymphocytes. Symptoms were associated with the increase in VL of both viruses and cytokine profile. Conclusions: Different immunological profiles were associated with EBV genotypes in primary infection, with EBV-2 being more frequent in patients with low levels of HIV viral load. With late infection monitoring and consequent delay in the initiation of HAART, clinical changes and effects on the maintenance of the immune response were observed.

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.

Virus-triggered secondary hemophagocytic lymphohistiocytosis

Primary (familial/hereditary) and secondary (non-familial/hereditary) hemophagocytic lymphohistiocytosis (HLH) are hyperinflammatory and hypercytokinemic syndromes. Secondary HLH includes infection- (eg viral/bacterial/fungal/parasitic) and non-infection- (eg collagen disease or malignancy) related diseases. Viral HLH is the major type among all age groups. Secondary viral HLH and primary HLH must be differentiated carefully because primary HLH can be associated with viral infection(s), and the outcome is dismal without a timely diagnosis and hematopoietic stem cell transplantation (HSCT). Epstein-Barr virus (EBV)-related HLH (EBV-HLH) is the most common type of viral HLH in childhood. For non-EBV-HLH, appropriate treatment of viral infection, followed by immunomodulatory agent(s) such as corticosteroids, intravenous immunoglobulin or cyclosporine A, is usually successful; however, recent SARS-CoV-2-related HLH may become life-threatening. EBV-HLH may occur heterogeneously associated with the primary infection, with chronic active EBV infection or with underlying primary HLH. Although immunomodulatory agent(s) are effective in the majority of EBV-HLH cases, management differs from that of non-EBV-HLH because severe and refractory cases may require etoposide-containing HLH-1994/2004 regimens or other experimental agents. The novel agent, emapalumab (an anti-IFN-γ monoclonal antibody) can be used to treat EBV-HLH cases to avoid the risk of secondary malignancy due to etoposide. Finally, HSCT is required for refractory EBV-HLH cases and can also be curative in some other cases.

Hypersensitivity to mosquito bites: A versatile Epstein-Barr virus disease with allergy, inflammation, and malignancy

Hypersensitivity to mosquito bites (HMB) is a rare disease characterized by transient intense skin reaction and systemic inflammation. Clinical presentation of HMB resembles other mosquito allergic responses, and it can also be difficult to clinically distinguish HMB from other severe allergic reactions. However, a distinctive pathophysiology underlies HMB. HMB belongs to a category of Epstein-Barr virus (EBV)-associated natural killer (NK) cell lymphoproliferative disorders (LPD). Hence, HMB may progress to systemic diseases, such as hemophagocytic lymphohistiocytosis, chronic active EBV disease, and EBV-associated malignancies. A triad of elevated serum IgE, NK lymphocytosis, and detection of EBV DNA in peripheral blood is commonly observed, and identification of EBV-infected NK cells usually facilitates the diagnosis. However, the effective treatment is limited, and its precise etiology remains unknown. Local CD4+ T cell proliferation triggered by mosquito bites appears to help induce EBV reactivation and EBV-infected NK-cell proliferation. These immunological interactions may explain the transient HMB signs and symptoms and the disease progression toward malignant LPD. Further research to elucidate the mechanism of HMB is warranted for better diagnosis and treatment of HMB and other forms of EBV-associated LPD.

Epstein-Barr Virus in Inborn Immunodeficiency-More Than Infection

Simple Summary

Epstein–Barr Virus (EBV) is a common virus that is readily controlled by a healthy immune system and rarely causes serious problems in infected people. However, patients with certain genetic defects of their immune system might have difficulties controlling EBV and often develop severe and life-threatening conditions, such as severe inflammation and malignancies. In this review, we provide a summary of inherited immune diseases that lead to a high susceptibility to EBV infection and discuss how this infection is associated with cancer development.

Abstract

Epstein–Barr Virus (EBV) is a ubiquitous virus affecting more than 90% of the world’s population. Upon infection, it establishes latency in B cells. It is a rather benign virus for immune-competent individuals, in whom infections usually go unnoticed. Nevertheless, EBV has been extensively associated with tumorigenesis. Patients suffering from certain inborn errors of immunity are at high risk of developing malignancies, while infection in the majority of immune-competent individuals does not seem to lead to immune dysregulation. Herein, we discuss how inborn mutations in TNFRSF9, CD27, CD70, CORO1A, CTPS1, ITK, MAGT1, RASGRP1, STK4, CARMIL2, SH2D1A, and XIAP affect the development, differentiation, and function of key factors involved in the immunity against EBV, leading to increased susceptibility to lymphoproliferative disease and lymphoma.

Epstein-Barr Virus-Associated T- and NK-Cell Lymphoproliferative Diseases: A Review of Clinical and Pathological Features

Simple Summary

In most Epstein–Barr virus (EBV)-infected individuals, the virus establishes a lifelong latent infection with no specific clinical manifestation. However, EBV primary infection and secondary reactivation may cause various EBV-associated lymphoproliferative disorders (LPD), including hematologic malignancies. Among them, EBV-positive T/NK LPD are uncommon diseases defined by the proliferation of T- or NK-cells infected by EBV, more commonly encountered in Asians and Latin Americans. They encompass a spectrum of disorders ranging from indolent reactive lesions to malignant and aggressive diseases. Despite novel insights from high-throughput molecular studies, the pathogenesis of these disorders is not well understood, and EBV-positive T/NK LPD diagnoses remain challenging due to their rarity and considerable overlap. Indeed, this article discusses new insights into EBV-positive T/NK LPD and focuses on diagnosis challenges, describing the difficulties to clarify the borders between overlapping LPD subtypes.

Abstract

Epstein–Barr virus (EBV) is a ubiquitous virus detected in up to 95% of the general population. Most people are asymptomatic, while some may develop a wide range of EBV-associated lymphoproliferative disorders (LPD). Among them, EBV-positive T/NK LPD are uncommon diseases defined by the proliferation of T- or NK-cells infected by EBV. The 2017 World Health Organization (WHO) classification recognizes the following entities characterized by different outcomes: chronic active EBV infection of T- or NK-cell types (cutaneous and systemic forms), systemic EBV-positive T-cell lymphoma of childhood, EBV-positive aggressive NK-cell leukemia, extra nodal NK/T-cell lymphoma nasal type, and the new provisional entity known as primary EBV-positive nodal T/NK-cell lymphoma. In addition, EBV associated-hemophagocytic lymphohistiocytosis is part of EBV-positive T/NK LPD, but has not been included in the WHO classification due to its reactive nature. Despite novel insights from high-throughput molecular studies, EBV-positive NK/T-cell LPD diagnoses remain challenging, especially because of their rarity and overlap. Until now, an accurate EBV-positive NK/T LPD diagnosis has been based on its clinical presentation and course correlated with its histological features. This review aims to summarize clinical, pathological and molecular features of EBV-positive T/NK LPD subtypes and to provide an overview of new understandings regarding these rare disorders.

Multiple Gastric Carcinomas Associated with Epstein-Barr Virus and Helicobacter pylori: A Thought-Provoking Case

BACKGROUND Epstein-Barr virus (EBV) and Helicobacter pylori (HP) infections are associated with gastric carcinoma (GC). We present a thought-provoking case of multiple GCs associated with EBV and HP infections. CASE REPORT HP infection was incidentally detected in an asymptomatic 60-year-old man. Upper endoscopy revealed gastric "kissing" ulcers. The lesions were located in the body of the stomach and measured 25 and 27 mm, respectively. They were diagnosed on pathology as moderately differentiated tubular adenocarcinoma. Imaging revealed no enlarged lymph nodes or distant metastatic lesions. Distal gastrectomy with lymphadenectomy was performed and surgical cure was obtained. The multiple GCs were categorized on pathology as infß ly0 v0 pT1b(SM)UL1N0M0H0P0CY0 pStage IA according to the Japanese classification and as T1bN0M0 Stage IA according to the tumor, node, metastasis classification. Pathological examination revealed remarkable lymphocytic infiltration into the stroma, as shown by in situ hybridization of EBV. These lymphocytic infiltrations were observed only at the sites of GC. In the immunohistochemical examination, in situ hybridization of EBV was positive for EBV-encoded small ribonucleic acid. The patient's postoperative course was uneventful. Hence, an unexpected relationship between EBV infection and multiple GCs was suggested by pathology. Quantitative determination of EBV DNA in peripheral blood was normal postoperatively. Adjuvant chemotherapy was not recommended. HP eradication therapy was successful. The patient remained asymptomatic and developed no recurrence or metastasis for 3 years after surgery. CONCLUSIONS This thought-provoking case suggests that coinfection with EBV and HP increases GC occurrence.

Clinicopathologic findings of chronic active Epstein-Barr virus infection in adults: A single-center retrospective study in China

Chronic active Epstein-Barr virus (CAEBV) infection is a rare disease with a high mortality rate. Our study aimed to summarize the clinicopathological characteristics of CAEBV infection in adults and improve knowledge of the disease. Data for 19 adult patients with CAEBV confirmed at our hospital from January 2010 to December 2019 were collected retrospectively. There were 14 males and 5 females, and the median age was 33 years (range 14-83). The main clinical manifestations included recurrent fever (84.2%, 16/19), splenomegaly (89.5%, 17/19), hepatomegaly (73.6%, 14/19), lymphadenopathy (42.1%, 8/19), abnormal liver function (78.9%, 15/19), hemopenia (94.7%, 18/19), and hemophagocytosis (52.6%, 10/19). A total of 22 specimens were collected from 19 patients for histopathology. Most of the biopsy specimens showed lymphocyte infiltration. Immunohistochemical staining and EBV-encoded small RNA (EBER) in situ hybridization were performed for 14 of the 22 samples. CD3 and CD20 staining were positive, with more CD3-positive cells than CD20-positive cells (100%, 14/14), and EBER in situ hybridization was positive in most cases (85.7%, 12/14). More than half of TCR gene rearrangement tests showed monoclonal rearrangement (66.6%, 4/6). Mortality was high, with most CAEBV patients dying during the period from diagnosis to the end of follow-up (12/19, 63%); the median survival time was only 20.75 months. Based on limited data, we consider that CAEBV is a disease with different ages of onset and is a complex and heterogeneous syndrome with features of both immunodeficiency and malignant neoplasms. Furthermore, the prognosis of adult-onset CAEBV appears to be very poor.

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.