Infectious mononucleosis

EBV-Associated Smooth Muscle Tumors With Autoimmune Hemolytic Anemia and Hepatitis B Infection: Report of a Previously Undescribed Neoplasm With Review

Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is rare in adults. The presence of intratumoral T lymphocytes and primitive rounded cells characterized this neoplasm. We report a 24-year-old Chinese man who developed EBV-SMT in the right adrenal gland with hepatitis B infection and autoimmune hemolytic anemia without a history of HIV infection, primary immune deficiency, organ transplantation, or malignant tumor. This patient had an unknown immunodeficient state. EBV-SMTs are commonly located in the liver, lung, and gastrointestinal tract but rarely in the adrenal gland. We reviewed 10 reported literature on EBV-SMT in the adrenal gland. It is imperative to distinguish EBV-SMT from conventional somatic smooth muscle tumors. The discovery of EBV-SMT forces the clinician to conduct a thorough evaluation of immune function and immune status surveillance, and these patients are vulnerable to subsequent malignant tumors.

Atypical presentation of spontaneous splenic rupture secondary to Epstein-Barr virus infection

We present a case of atraumatic splenic rupture secondary to Epstein-Barr virus (EBV) infection in a woman in her early 50s. The patient initially presented with sepsis secondary to pneumonia but then developed abdominal pain and distension. CT revealed splenic rupture with a significant perisplenic hematoma. Laboratory tests confirmed an EBV infection. Owing to frailty, she underwent fluoroscopy-guided splenic artery embolisation. This case highlights the rare risk of splenic rupture following EBV infection, even in the absence of typical symptoms of infectious mononucleosis.

A cocktail nanovaccine targeting key entry glycoproteins elicits high neutralizing antibody levels against EBV infection

Epstein-Barr virus (EBV) infects more than 95% of adults worldwide and is closely associated with various malignancies. Considering the complex life cycle of EBV, developing vaccines targeting key entry glycoproteins to elicit robust and durable adaptive immune responses may provide better protection. EBV gHgL-, gB- and gp42-specific antibodies in healthy EBV carriers contributed to sera neutralizing abilities in vitro, indicating that they are potential antigen candidates. To enhance the immunogenicity of these antigens, we formulate three nanovaccines by co-delivering molecular adjuvants (CpG and MPLA) and antigens (gHgL, gB or gp42). These nanovaccines induce robust humoral and cellular responses through efficient activation of dendritic cells and germinal center response. Importantly, these nanovaccines generate high levels of neutralizing antibodies recognizing vulnerable sites of all three antigens. IgGs induced by a cocktail vaccine containing three nanovaccines confer superior protection from lethal EBV challenge in female humanized mice compared to IgG elicited by individual NP-gHgL, NP-gB and NP-gp42. Importantly, serum antibodies elicited by cocktail nanovaccine immunization confer durable protection against EBV-associated lymphoma. Overall, the cocktail nanovaccine shows robust immunogenicity and is a promising candidate for further clinical trials.

Evaluation of novel Epstein-Barr virus-derived antigen formulations for monitoring virus-specific T cells in pediatric patients with infectious mononucleosis

BACKGROUND

Infection with the Epstein-Barr virus (EBV) elicits a complex T-cell response against a broad range of viral proteins. Hence, identifying potential differences in the cellular immune response of patients with different EBV-associated diseases or different courses of the same disorder requires interrogation of a maximum number of EBV antigens. Here, we tested three novel EBV-derived antigen formulations for their ability to reactivate virus-specific T cells ex vivo in patients with EBV-associated infectious mononucleosis (IM).

METHODS

We comparatively analyzed EBV-specific CD4+ and CD8+ T-cell responses to three EBV-derived antigen formulations in 20 pediatric patients during the early phase of IM: T-activated EBV proteins (BZLF1, EBNA3A) and EBV-like particles (EB-VLP), both able to induce CD4+ and CD8+ T-cell responses ex vivo, as well as an EBV-derived peptide pool (PP) covering 94 well-characterized CD8+ T-cell epitopes. We assessed the specificity, magnitude, kinetics, and functional characteristics of EBV-specific immune responses at two sequential time points (v1 and v2) within the first six weeks after IM symptom onset (Tonset).

RESULTS

All three tested EBV-derived antigen formulations enabled the detection of EBV-reactive T cells during the early phase of IM without prior T-cell expansion in vitro. EBV-reactive CD4+ and CD8+ T cells were mainly mono-functional (CD4+: mean 64.92%, range 56.15-71.71%; CD8+: mean 58.55%, range 11.79-85.22%) within the first two weeks after symptom onset (v1) with IFN-γ and TNF-secreting cells representing the majority of mono-functional EBV-reactive T cells. By contrast, PP-reactive CD8+ T cells were primarily bi-functional (>60% at v1 and v2), produced IFN-γ and TNF and had more tri-functional than mono-functional components. We observed a moderate correlation between viral load and EBNA3A, EB-VLP, and PP-reactive CD8+ T cells (rs = 0.345, 0.418, and 0.356, respectively) within the first two weeks after Tonset, but no correlation with the number of detectable EBV-reactive CD4+ T cells.

CONCLUSIONS

All three EBV-derived antigen formulations represent innovative and generic recall antigens suitable for monitoring EBV-specific T-cell responses ex vivo. Their combined use facilitates a thorough analysis of EBV-specific T-cell immunity and allows the identification of functional T-cell signatures linked to disease development and severity.

Acute Appendicitis in the Setting of Infectious Mononucleosis: A Case Report

Infectious mononucleosis (IM) is a viral illness caused by the Epstein-Barr virus that typically manifests with pharyngitis, lymphadenopathy, and fatigue. In rare cases, IM can cause acute appendicitis. We present the case of an 18-year-old female who arrived at the emergency department with worsening abdominal pain and an ongoing cough. Initial imaging showed a questionably dilated appendix, and a follow-up examination revealed cervical lymphadenopathy. She later returned to the ED with severe abdominal pain, clinical signs of acute appendicitis, and a positive monospot test, which led to an appendectomy. This case illustrates the need for complete history taking and thorough physical examination in patients with acute appendicitis, as their condition may be due to an atypical underlying cause.

Epstein-Barr virus-associated post-transplant lymphoproliferative disorders in pediatric transplantation: A prospective multicenter study in the United States

BACKGROUND

Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disorders (PTLD) is the most common malignancy in children after transplant; however, difficulties for early detection may worsen the prognosis.

METHODS

The prospective, multicenter, study enrolled 944 children (≤21 years of age). Of these, 872 received liver, heart, kidney, intestinal, or multivisceral transplants in seven US centers between 2014 and 2019 (NCT02182986). In total, 34 pediatric EBV+ PTLD (3.9%) were identified by biopsy. Variables included sex, age, race, ethnicity, transplanted organ, EBV viral load, pre-transplant EBV serology, immunosuppression, response to chemotherapy and rituximab, and histopathological diagnosis.

RESULTS

The uni-/multivariable competing risk analyses revealed the combination of EBV-seropositive donor and EBV-naïve recipient (D+R-) was a significant risk factor for PTLD development (sub-hazard ratio: 2.79 [1.34-5.78], p = .006) and EBV DNAemia (2.65 [1.72-4.09], p < .001). Patients with D+R- were significantly more associated with monomorphic/polymorphic PTLD than those with the other combinations (p = .02). Patients with monomorphic/polymorphic PTLD (n = 21) had significantly more EBV DNAemia than non-PTLD patients (p < .001) and an earlier clinical presentation of PTLD than patients with hyperplasias (p < .001), within 6-month post-transplant. Among non-liver transplant recipients, monomorphic/polymorphic PTLD were significantly more frequent than hyperplasias in patients ≥5 years of age at transplant (p = .01).

CONCLUSIONS

D+R- is a risk factor for PTLD and EBV DNAemia and associated with the incidence of monomorphic/polymorphic PTLD. Intensive follow-up of EBV viral load within 6-month post-transplant, especially for patients with D+R- and/or non-liver transplant recipients ≥5 years of age at transplant, may help detect monomorphic/polymorphic PTLD early in pediatric transplant.

What rheumatologists need to know about mRNA vaccines: current status and future of mRNA vaccines in autoimmune inflammatory rheumatic diseases

Messenger RNA (mRNA) vaccines as a novel vaccine platform offer new tools to effectively combat both emerging and existing pathogens which were previously not possible. The 'plug and play' feature of mRNA vaccines enables swift design and production of vaccines targeting complex antigens and rapid incorporation of new vaccine constituents as needed. This feature makes them likely to be adopted for widespread clinical use in the future.Currently approved mRNA vaccines include only those against SARS-CoV-2 virus. These vaccines demonstrate robust immunogenicity and offer substantial protection against severe disease. Numerous mRNA vaccines against viral pathogens are in the early to late phase of development. Several mRNA vaccines for influenza are tested in clinical trials, with some already in phase 3 studies. Other vaccines in the early and late phases of development include those targeting Cytomegalovirus, varicella zoster virus, respiratory syncytial virus and Epstein-Barr virus. Many of these vaccines will likely be indicated for immunosuppressed populations including those with autoimmune inflammatory rheumatic diseases (AIIRD). This review focuses on the mechanism, safety and efficacy of mRNA in general and summarises the status of mRNA vaccines in development for common infectious diseases of particular interest for patients with AIIRD.

Mitochondrial DNA Missense Mutations ChrMT: 8981A > G and ChrMT: 6268C > T Identified in a Caucasian Female with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Triggered by the Epstein-Barr Virus

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a multisystem disabling disease with unclear etiology and pathophysiology, whose typical symptoms include prolonged debilitating recovery from fatigue or postexertional malaise (PEM). Disrupted production of adenosine triphosphate (ATP), the intracellular energy that fuels cellular activity, is a cause for fatigue. Here, we present a long-term case of ME/CFS: a 75-year-old Caucasian female patient, whose symptoms of ME/CFS were clearly triggered by an acute infection of the Epstein-Barr virus 24 years ago (mononucleosis). Before then, the patient was a healthy professional woman. A recent DNA sequence analysis identified missense variants of mitochondrial respiratory chain enzymes, including ATP6 (ChrMT: 8981A > G; Q152R) and Cox1 (ChrMT: 6268C > T; A122V). Protein subunits ATP6 and Cox1 are encoded by mitochondrial DNA outside of the nucleus: the Cox1 gene encodes subunit 1 of complex IV (CIV: cytochrome c oxidase) and the ATP6 gene encodes subunit A of complex V (CV: ATP synthase). CIV and CV are the last two of five essential enzymes that perform the mitochondrial electron transport respiratory chain reaction to generate ATP. Further analysis of the blood sample using transmission electron microscopy demonstrated abnormal, circulating, extracellular mitochondria. These results indicate that the patient had dysfunctional mitochondria, which may contribute directly to her major symptoms, including PEM and neurological and cognitive changes. Furthermore, the identified variants of ATP6 (ChrMT: 8981A > G; Q152R) and Cox1 (ChrMT: 6268C > T; A122V), functioning at a later stage of mitochondrial ATP production, may play a role in the abnormality of the patient's mitochondria and the development of her ME/CFS symptoms.

Splenic Infarction Due to Epstein-Barr Virus: A Case Report and Literature Review

Splenic infarction is a rare and likely underdiagnosed complication of Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Here, we describe an 18-year-old Guyanese male with persistent severe left-sided abdominal pain found to be EBV positive and have a large splenic infarct, along with a transient decrease in protein C, protein S, and antithrombin III activity levels. He was treated with supportive care and anticoagulated with heparin and apixaban. We review prior reports and perspectives on underlying pathophysiology, diagnosis, and the management of these cases, which likely do not require anticoagulation but may be considered on a per-case basis.

Risk of multiple sclerosis in individuals with infectious mononucleosis: a national population-based cohort study using hospital records in England, 2003-2023

BACKGROUND

Epstein-Barr virus (EBV) is thought to be a necessary causative agent in the development of multiple sclerosis (MS). Infectious mononucleosis (IM), which occurs up to 70% of adolescents and young adults with primary EBV infection, appears to be a further risk factor but few studies have been highly powered enough to explore this association by time since IM diagnosis.

OBJECTIVE

The objective was to quantify the risk of MS in individuals with IM compared with the general population, with particular focus on time since IM diagnosis.

METHODS

In this retrospective cohort study using English national Hospital Episode Statistics from 2003 to 2023, patients with a hospital diagnosis of IM were compared with the general population for MS incidence.

RESULTS

MS incidence in patients with IM was nearly three times higher than the general population after multivariable adjustment (adjusted hazard ratio = 2.8, 95% confidence interval (CI = 2.3-3.4), driven by strong associations at long time intervals (>5 years) between IM diagnosis and subsequent MS diagnosis.

CONCLUSION

While EBV infection may be a prerequisite for MS, the disease process of IM (i.e. the body's defective immune response to primary EBV infection) seems to be, in addition, implicated over the long term.

Severe Upper Airway Obstruction in a Patient With Infectious Mononucleosis

Infectious mononucleosis (IM) is a clinical disease caused by the Epstein-Barr virus (EBV). Common presenting symptoms include sore throat, lymph node enlargement, fever, and malaise. Although severe upper airway obstruction is uncommon, it is a potentially fatal complication that requires immediate intervention. We describe the case of an 18-year-old Hispanic man who presented with a progressive sore throat and difficulty speaking, requiring endotracheal intubation for airway protection. CT images showed diffuse swelling of Waldeyer's tonsillar ring, multiple enlarged lymphadenopathies, and splenomegaly. Acute EBV infection was confirmed considering clinical presentation and using the heterophile antibody, anti-nuclear and anti-viral capsid antigens, and quantitative PCR. The patient was managed with ventilatory support, empirical antibiotic therapy, and systemic corticosteroids, achieving a positive outcome. Our case illustrates the use of corticosteroids in managing severe upper airway obstruction complicating IM.

Acalculous Cholecystitis as a Complication of Primary Epstein-Barr Virus Infection: A Case-Based Scoping Review of the Literature

Primary Epstein-Barr virus (EBV) infection manifests with diverse clinical symptoms, occasionally resulting in severe complications. This scoping review investigates the rare occurrence of acute acalculous cholecystitis (AAC) in the context of primary EBV infection, with a focus on understanding its prevalence, clinical features, and underlying mechanisms. The study also explores EBV infection association with Gilbert syndrome, a condition that potentially exacerbates the clinical picture. Additionally, a case report of an 18-year-old female presenting with AAC and ascites secondary to EBV infection enhances the review. A comprehensive literature review was conducted, analyzing reported cases of AAC secondary to EBV infection. This involved examining patient demographics, clinical presentations, laboratory findings, and outcomes. The search yielded 44 cases, predominantly affecting young females. Common clinical features included fever, cervical lymphadenopathy, tonsillitis/pharyngitis, and splenomegaly. Laboratory findings highlighted significant hepatic involvement. The review also noted a potential link between AAC in EBV infection and Gilbert syndrome, particularly in cases with abnormal bilirubin levels. AAC is a rare but significant complication of primary EBV infection, primarily observed in young females, and may be associated with Gilbert syndrome. This comprehensive review underscores the need for heightened clinical awareness and timely diagnosis to manage this complication effectively.

Membranous tonsillitis: Aetiology, prevalence and prescribing patterns in patients with upper respiratory tract infection

Background Membranous tonsillitis is one of the most common forms of acute tonsillitis in childhood. Although many different microorganisms may cause this disease, clinicians generally consider bacterial agents as a possible cause and prescribe a penicillin-group of antibiotic. This study aimed to determine the aetiology of membranous tonsillitis and prescribing errors. In addition, we investigated the effectiveness of epidemiological, clinical and laboratory parameters and their role in guiding treatment. Methods We did this retrospective study at the paediatric emergency department of a tertiary referral hospital including 423 outpatient children aged 0 to 18 years diagnosed with membranous tonsillitis. Results Group A beta-haemolytic streptococcus was found in 132 (31.2%) patients, Epstein-Barr virus (EBV) in 103 (24.3%), and other viral aetiologies in 188 (44.4%). The prescription rate of antibiotics in the EBV-positive group was 27%, and Downey cells were seen at a rate of 98% in this group. Only 7% of patients with a positive throat culture were started on appropriate antibiotics. Conclusion EBV and group A beta-haemolytic streptococcus were the most common causes of membranous tonsillitis. Throat culture and peripheral blood smears are the most useful tests for paediatric emergency clinicians; these are fast and can help ensure correct diagnosis and guide treatment in almost all patients.

Comparison of Eosinophil Counts in Inflammatory Conditions: Multisystem Inflammatory Syndrome in Children, Kawasaki Disease, and Infectious Mononucleosis

This study examined the distinctions between multisystem inflammatory syndrome associated with coronavirus disease 2019, Kawasaki disease, and infectious mononucleosis. These three inflammatory disorders have commonalities according to clinical and laboratory results, particularly in relation to eosinophil levels. In this retrospective, single-center study, we documented the examination records (acute phase reactants and complete blood count) and clinical and cardiological findings of 130 patients diagnosed with multisystem inflammatory syndrome, Kawasaki disease, and infectious mononucleosis. These patients were treated and received follow-up care in our hospital from March 12, 2020, to September 13, 2022, as per the hospital records. Statistical analyses were performed using NCSS 2007, version 1 software. Eosinopenia was more prevalent in children with multisystem inflammatory syndrome than in those with Kawasaki disease, who showed normal or elevated eosinophil counts. The eosinophil counts in patients with infectious mononucleosis typically fell within the normal range. Our study found no correlation between the eosinophil counts and cardiac involvement in pediatric patients with either condition. These findings indicate a higher prevalence of eosinopenia in patients with multisystem inflammatory syndrome, irrespective of cardiac involvement, than in those with Kawasaki disease. Despite similarities in clinical findings, Kawasaki disease and multisystem inflammatory syndrome in children necessitate further studies for distinct characteristic elucidation.

Cytokine Storm Syndromes Associated with Epstein-Barr Virus

Epstein-Barr virus (EBV) is a ubiquitous and predominantly B cell tropic virus. One of the most common viruses to infect humans, EBV, is best known as the causative agent of infectious mononucleosis (IM). Although most people experience asymptomatic infection, EBV is a potent immune stimulus and as such it elicits robust proliferation and activation of the B-lymphocytes it infects as well as the immune cells that respond to infection. In certain individuals, such as those with inherited or acquired defects affecting the immune system, failure to properly control EBV leads to the accumulation of EBV-infected B cells and EBV-reactive immune cells, which together contribute to the development of often life-threatening cytokine storm syndromes (CSS). Here, we review the normal immune response to EBV and discuss several CSS associated with EBV, such as chronic active EBV infection, hemophagocytic lymphohistiocytosis, and post-transplant lymphoproliferative disorder. Given the critical role for cytokines in driving inflammation and contributing to disease pathogenesis, we also discuss how targeting specific cytokines provides a rational and potentially less toxic treatment for EBV-driven CSS.

A Case Report of a Rapidly Progressive Epstein-Barr Virus Encephalitis Infection in an Adult With HIV on Highly Active Antiretroviral Therapy

Epstein-Barr virus (EBV) encephalitis is a rare complication of EBV infection, with most cases described in children. Although some cases of EBV encephalitis have been reported in adults, they have occurred in the presence of other central nervous system infections, superimposed on an underlying neurocognitive disorder, or in immunocompromised states. We present herein a rare case of rapidly progressive EBV encephalitis in an adult male with HIV infection on highly active antiretroviral therapy (HAART) with no pre-existing neurocognitive symptoms. A 52-year-old African American man with HIV infection on HAART presented with acute altered mental status and weakness. On admission, he had normal muscle tone and reflexes, with no signs of meningism. Head CT without contrast showed no acute intracranial pathology. Blood and urine cultures were negative. CSF analysis was suggestive of a viral infection. Viral studies were positive only for EBV DNA by PCR in CSF. The patient received IV acyclovir for two weeks, followed by four weeks of oral valacyclovir with full recovery. Clinicians should consider a diagnosis of EBV encephalitis in HIV-positive patients on HAART who present with acute altered mental status. Treatment with antiviral therapy should be considered in patients with EBV encephalitis.

Infectious leukoencephalopathies

Leukoencephalopathy from infectious agents may have a rapid course, such as human simplex virus encephalitis; however, in many diseases, it may take months or years before diagnosis, such as in subacute sclerosing panencephalitis or Whipple disease. There are wide geographic distributions and susceptible populations, including both immunocompetent and immunodeficient patients. Many infections have high mortality rates, such as John Cunningham virus and subacute sclerosing panencephalitis, although others have effective treatments if suspected and treated early, such as herpes simplex encephalitis. This chapter will describe viral, bacterial, and protozoal infections, which predominantly cause leukoencephalopathy. We focus on the clinical presentation of these infectious agents briefly covering epidemiology and subtypes of infections. Next, we detail current pathophysiologic mechanisms causing white matter injury. Diagnostic and confirmatory tests are discussed. We cover predominantly MRI imaging features of leukoencephalopathies, and in addition, summarize the common imaging features. Additionally, we detail how imaging features may be used to narrow the differential of a leukoencephalopathy clinical presentation. Lastly, we present an outline of common treatment approaches where available.

EBV-microRNAs as Potential Biomarkers in EBV-related Fever: A Narrative Review

At present, timely and accurate diagnosis and effective treatment of Epstein- Barr Virus (EBV) infection-associated fever remain a difficult challenge. EBV encodes 44 mature microRNAs (miRNAs) that inhibit viral lysis, adjust inflammatory response, regulate cellular apoptosis, promote tumor genesis and metastasis, and regulate tumor cell metabolism. Herein, we have collected the specific expression data of EBV-miRNAs in EBV-related fevers, including infectious mononucleosis (IM), EBVassociated hemophagocytic lymphohistiocytosis (EBV-HLH), chronic active EBV infection (CAEBV), and EBV-related tumors, and proposed the potential value of EBVmiRNAs as biomarkers to assist in the identification, diagnosis, and prognosis of EBVrelated fever, as well as therapeutic targets for drug development.

No Additional Risk of Ampicillin Rash Among Pediatric Liver Transplant Recipients With Concurrent Epstein-Barr Virus Infection

BACKGROUND

Epstein-Barr virus (EBV) infection frequently develops in children undergoing liver transplantation (LT) because of mandated immunosuppressive therapy. There is a risk of ampicillin rash when penicillin derivatives are used in patients with EBV-associated infectious mononucleosis. Hence, the administration of penicillin derivatives may raise concerns about ampicillin rash in patients with high EBV loads. However, no studies confirmed the risk of administering penicillin derivatives to EBV-infected children after LT.

METHODS

This retrospective study was conducted at the largest pediatric transplantation center in Japan. We investigated all pediatric liver transplant recipients who received penicillin derivatives within 2 years of LT between 2014 and 2020. We separated the cohort into EBV-positive and EBV-negative groups to assess the frequency of ampicillin and antibiotic-associated rash.

RESULTS

Two hundred eighty-six liver transplant recipients were enrolled. There were 111 recipients in the EBV-positive group and 175 recipients in the EBV-negative group. In the EBV-positive group, 49 patients had high EBV DNA loads (≥1000 copies/µg DNA). None of the patients in either group developed ampicillin rash, and the frequency of antibiotic-associated rash did not differ [8/111 (7.2%) vs. 10/175 (5.7%), P = 0.797]. Additional subgroup analysis revealed no difference in the frequency of antibiotic-associated rashes regardless of the presence or absence of high EBV loads.

CONCLUSIONS

In this study, ampicillin rash was not observed, and antibiotic-associated rash was not associated with concurrent EBV infection. Penicillin derivatives can be used safely, even in liver transplant recipients with persistent asymptomatic EBV infection.

A prospective evaluation of the diagnostic potential of EBV-DNA in plasma and whole blood

BACKGROUND

Quantitative polymerase chain reaction (qPCR) for Epstein-Barr virus (EBV)-DNA is an important diagnostic tool for EBV-associated disease, but interpretation of its clinical significance is challenging.

OBJECTIVES

We assessed the diagnostic and clinical performance of WHO-standardised qPCR for EBV-DNA (WHO EBV-qPCR) in plasma and whole blood (WB) for proven EBV disease in a prospectively accrued patient cohort.

STUDY DESIGN

Central Denmark Region patients, tested with WHO EBV-qPCR from November 2017 to March 2019, were screened for EBV disease. Incidence (IR) was estimated by Poisson regression. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were calculated for EBV-qPCR in plasma and WB. Risk of diagnostic latency was compared between patients with EBV-positive and EBV-negative lymphomas.

RESULTS

EBV disease was diagnosed in 95 of 1484 participants (IR: 16.3 per 1000 patientyears 95%CI; 13.3-19.9). Sensitivity and specificity of WHO EBV-qPCR in plasma was 82.4% (95% CI; 74.2-90.7%) and 87.8% (95% CI; 85.6-90%), yielding a PPV of 32.2% (95% CI; 24.9-39.5%) and NPV of 98.6% (95% CI; 97.7-99.5%) for proven EBV disease. Sensitivity and NPV were comparable in WB, while specificity and PPV decreased to 66.9% (95% CI; 60.6-73.1%) and 18.1% (95% CI; 7.5-28.7%). Risk of diagnostic latency was 2.3-fold (95% CI 1.4-4.1) higher for patients with EBV-positive compared with EBV-negative lymphomas.

CONCLUSIONS

WHO EBV-qPCR in plasma and WB have a low PPV but a high NPV for proven EBV disease. Implementation of WHO EBV-qPCR could improve interpretation and facilitate EBV-positive lymphoma diagnosis.

The Burden of Epstein-Barr Virus (EBV) and Its Determinants among Adult HIV-Positive Individuals in Ethiopia

Epstein-Barr virus (EBV) is a well-known risk factor for the development of nasopharyngeal carcinoma, Hodgkin's lymphoma (HL), and Non-Hodgkin's lymphoma (NHL). People with HIV infection (PWH) are at increased risk for EBV-associated malignancies such as HL and NHL. Nevertheless, there are limited data on the burden of EBV among this population group in Ethiopia. Hence, this study aimed to determine the burden of EBV infection among adult HIV-positive individuals in Ethiopia and assess the determinants of EBV DNA positivity. We conducted a cross-sectional study at the Tikur Anbessa Specialised Hospital from March 2020 to March 2021. Two hundred and sixty individuals were enrolled in this study, including 179 HIV-positive and 81 HIV-negative individuals. A structured questionnaire was used to capture demographic and individual attributes. In addition, the clinical data of patients were also retrieved from clinical records. EBV viral capsid antigen (VCA) IgG antibody was measured by multiplex flow immunoassay, and EBV DNA levels were tested by quantitative real-time polymerase chain reaction (q-PCR) assays targeting the EBNA-1 open reading frame (ORF). Descriptive statistics were conducted to assess each study variable. A multivariable logistic regression model was applied to evaluate the determinants of EBV infection. Statistical significance was determined at a p-value < 0.05. Two hundred and fifty-three (97.7%) study participants were seropositive for the EBV VCA IgG antibody. Disaggregated by HIV status, 99.4% of HIV-positive and 93.8% of HIV-negative participants were EBV seropositive. In this study, 49.7% of HIV-positive and 24.7% of HIV-negative individuals were EBV DNA positive. PWH had a higher risk of EBV DNA positivity at 3.05 times (AOR: 3.05, 95% CI: 1.40-6.67). Moreover, among PWH, those with an HIV viral load greater than 1000 RNA copies/mL (AOR = 5.81, 95% CI = 1.40, 24.13) had a higher likelihood of EBV DNA positivity. The prevalence of EBV among PWH was significantly higher than among HIV-negative individuals. Higher HIV viral loads in PWH were associated with an increased risk of EBV DNA positivity. Since the increases in the viral load of EBV DNA among PWH could be related to the risk of developing EBV-associated cancers, it is necessary for more research on the role of EBV in EBV-associated cancer in this population group to be carried out.

Diagnostic Value of Dynamic 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (18F-FDG PET-CT) in Cervical Lymph Node Metastasis of Nasopharyngeal Cancer

BACKGROUND AND PURPOSE

Dynamic 18F-FDG PET-CT scanning can accurately quantify 18F-FDG uptake and has been successfully applied in diagnosing and evaluating therapeutic effects in various malignant tumors. There is no conclusion as to whether it can accurately distinguish benign and malignant lymph nodes in nasopharyngeal cancer. The main purpose of this study is to reveal the diagnostic value of dynamic PET-CT in cervical lymph node metastasis of nasopharyngeal cancer through analysis.

METHOD

We first searched for cervical lymph nodes interested in static PET-CT, measured their SUV-Max values, and found the corresponding lymph nodes in magnetic resonance images before and after treatment. The valid or invalid groups were included according to the changes in lymph node size before and after treatment. If the change in the product of the maximum diameter and maximum vertical transverse diameter of the lymph node before and after treatment was greater than or equal to 50%, they would be included in the valid group. If the change was less than 50%, they would be included in the invalid group. Their Ki values were measured on dynamic PET-CT and compared under different conditions. Then, we conducted a correlation analysis between various factors and Ki values. Finally, diagnostic tests were conducted to compare the sensitivity and specificity of Ki and SUV-Max.

RESULT

We included 67 cervical lymph nodes from different regions of 51 nasopharyngeal cancer patients and divided them into valid and invalid groups based on changes before treatment. The valid group included 50 lymph nodes, while the invalid group included 17. There wer significant differences (p < 0.001) between the valid and the invalid groups in SUV-Max, Ki-Mean, and Ki-Max values. When the SUV-Max was ≤4.5, there was no significant difference in the Ki-Mean and Ki-Max between the two groups (p > 0.05). When the SUV-Max was ≤4.5 and pre-treatment lymph nodes were <1.0 cm, the valid group had significantly higher Ki-Mean (0.00910) and Ki-Maximum (0.01004) values than the invalid group (Ki-Mean = 0.00716, Ki-Max = 0.00767) (p < 0.05). When the SUV-Max was ≤4.5, the pre-treatment lymph nodes < 1.0 cm, and the EBV DNA replication normal, Ki-Mean (0.01060) and Ki-Max (0.01149) in the valid group were still significantly higher than the invalid group (Ki-Mean = 0.00670, Ki-Max = 0.00719) (p < 0.05). The correlation analysis between different factors (SUV-Max, T-stage, normal EB virus DNA replication, age, and pre-treatment lymph node < 1.0 cm) and the Ki value showed that SUV-Max and a pre-treatment lymph node < 1.0 cm were related to Ki-Mean and Ki-Max. Diagnostic testing was conducted; the AUC value of the SUV-Max value was 0.8259 (95% confidence interval: 0.7296-0.9222), the AUC value of the Ki-Mean was 0.8759 (95% confidence interval: 0.7950-0.9567), and the AUC value of the Ki-Max was 0.8859 (95% confidence interval: 0.8089-0.9629). After comparison, it was found that there was no significant difference in AUC values between Ki-Mean and SUV-Max (p = 0.220 > 0.05), and there was also no significant difference in AUC values between Ki max and SUV-Max (p = 0.159 > 0.05). By calculating the Youden index, we identified the optimal cut-off value. It was found that the sensitivity of SUV-Max was 100% and the specificity was 66%, the sensitivity of Ki-Mean was 100% and the specificity was 70%, and the sensitivity of Ki-Max was 100% and the specificity was 72%. After Chi-Square analysis, it was found that there was no significant difference in specificity between Ki-Mean and SUV-Max (p = 0.712), and there was also no significant difference in specificity between Ki-Max and SUV-Max (p = 0.755).

CONCLUSION

Dynamic PET-CT has shown a significant diagnostic value in diagnosing cervical lymph node metastasis of nasopharyngeal cancer, especially for the small SUV value, and lymph nodes do not meet the metastasis criteria before treatment, and EBV DNA replication is normal. Although the diagnostic accuracy, sensitivity, and specificity of dynamic PET-CT were not significantly different from traditional static PET-CT, the dynamic PET-CT had a more accurate tendency.

Interleukin-37 is involved in the immunopathogenesis of infectious mononucleosis

BACKGROUND

Multiple immunopathological responses to viruses are observed in infectious mononucleosis (IM), a manifestation of primary infection with Epstein-Barr virus (EBV). Protective effects of the negative immunoregulatory molecule interleukin-37 (IL-37) have been observed in various bacterial and viral infections. However, the function of IL-37 in IM remains unknown.

METHODS

Flow cytometry and enzyme-linked immunosorbent assay (ELISA) were used to determine the expression of IL-37 in the peripheral blood of patients diagnosed with IM, and the variation of lymphocyte subsets. Furthermore, the associations between IL-37 expression and the percentage of lymphocyte subgroups were analyzed.

RESULTS

Patients with IM had severe immune dysfunction. The control group had a lower expression of IL-37 than the patients with IM. There were significant associations between IL-37 expression and both the proportion of CD3⁺T cells and the ratio of CD3⁺CD4⁺ to CD3⁺CD8⁺T cells. Patients with higher levels of IL-37 expression had lower levels of the liver inflammation indicators, alanine aminotransferase (ALT) and aspartate aminotransferase (AST).

CONCLUSIONS

IL-37 may affect the immune pathogenesis of patients with IM infected with EBV, and may have immunotherapeutic benefit for EBV-associated illnesses.

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.

Diagnosis of Epstein-Barr and cytomegalovirus infections using decision trees: an effective way to avoid antibiotic overuse in paediatric tonsillopharyngitis

BACKGROUND

The incidence of tonsillopharyngitis is especially prevalent in children. Despite the fact that viruses cause the majority of infections, antibiotics are frequently used as a treatment, contrary to international guidelines. This is not only an inappropriate method of treatment for viral infections, but it also significantly contributes to the emergence of antibiotic-resistant strains. In this study, EBV and CMV-related tonsillopharyngitis were distinguished from other pathogens by using machine learning techniques to construct a classification tree based on clinical characteristics.

MATERIALS AND METHODS

In 2016 and 2017, we assessed information regarding 242 children with tonsillopharyngitis. Patients were categorized according to whether acute cytomegalovirus or Epstein-Barr virus infections were confirmed (n = 91) or not (n = 151). Based on symptoms and blood test parameters, we constructed decision trees to discriminate the two groups. The classification efficiency of the model was characterized by its sensitivity, specificity, positive predictive value, and negative predictive value. Fisher's exact and Welch's tests were used to perform univariable statistical analyses.

RESULTS

The best decision tree distinguished EBV/CMV infection from non-EBV/CMV group with 83.33% positive predictive value, 88.90% sensitivity and 90.30% specificity. GPT (U/l) was found to be the most discriminatory variable (p < 0.0001). Using the model, unnecessary antibiotic treatment could be reduced by 66.66% (p = 0.0002).

DISCUSSION

Our classification model can be used as a diagnostic decision support tool to distinguish EBC/CMV infection from non EBV/CMV tonsillopharyngitis, thereby significantly reducing the overuse of antibiotics. It is hoped that the model may become a tool worth considering in routine clinical practice and may be developed to differentiate between viral and bacterial infections.

Association between Antibiotic Exposure and the Risk of Rash in Children with Infectious Mononucleosis: a Multicenter, Retrospective Cohort Study

Present evidence suggests that the administration of antibiotics, particularly aminopenicillins, may increase the risk of rash in children with infectious mononucleosis (IM). This retrospective, multicenter cohort study of children with IM was conducted to explore the association between antibiotic exposure in IM children and the risk of rash. A robust error generalized linear regression was performed to address the potential cluster effect, as well as confounding factors such as age and sex. A total of 767 children (aged from 0 to 18 years) with IM from 14 hospitals in Guizhou Province were included in the final analysis. The regression analysis implied that exposure to antibiotics was associated with a significantly increased incidence of overall rash in IM children (adjusted odds ratio [AOR], 1.47; 95% confidence interval [CI], ~1.04 to 2.08; P = 0.029). Of 92 overall rash cases, 43 were probably related to antibiotic exposure: two cases (4.08%) in the amoxicillin-treated group and 41 (8.15%) in the group treated with other antibiotics. Regression analysis indicated that the risk of rash induced by amoxicillin in IM children was similar to that induced by other penicillins (AOR, 1.12; 95% CI, ~0.13 to 9.67), cephalosporins (AOR, 2.45; 95% CI, ~0.43 to 14.02), or macrolides (AOR, 0.91; 95% CI, ~0.15 to 5.43). Antibiotic exposure may be associated with an increased risk of overall rash in IM children, but amoxicillin was not found to be associated with any increased risk of rash during IM compared to other antibiotics. We suggest that clinicians be vigilant against the occurrence of rash in IM children receiving antibiotic therapy, rather than indiscriminately avoiding prescribing amoxicillin.

Immunity and Immune Evasion Mechanisms of Epstein-Barr Virus

Epstein-Barr virus (EBV) is the first human oncogenic virus to be identified, which evades the body's immune surveillance through multiple mechanisms that allow long-term latent infection. Under certain pathological conditions, EBVs undergo a transition from the latent phase to the lytic phase and cause targeted dysregulation of the host immune system, leading to the development of EBV-related diseases. Therefore, an in-depth understanding of the mechanism of developing an immune response to EBV and the evasion of immune recognition by EBV is important for the understanding of the pathogenesis of EBV, which is of great significance for finding strategies to prevent EBV infection, and developing a therapy to treat EBV-associated diseases. In this review, we will discuss the molecular mechanisms of host immunological responses to EBV infection and the mechanisms of EBV-mediated immune evasion during chronic active infection.

Eyelid Edema May Be as a Sign of Dacryoadenitis in the Course of Epstein-Barr Virus Infectious Mononucleosis

Epstein-Barr virus (EBV) is a widespread virus that causes frequent, in many cases asymptomatic, infections. Mononucleosis is the most frequent clinical syndrome encountered during EBV infection. In rare cases, the disease can present at the onset with atypical signs that make an immediate diagnostic classification difficult. An example in this sense is the onset of dacryoadenitis with consequent eyelid edema. In these cases, it is difficult to immediately recognize this sign as referable to mononucleosis and it appears necessary to carry out a series of analyses aimed at excluding any other edematous causes. We describe below a clinical case of dacryoadenitis in the course of infectious mononucleosis and a review of similar cases described in the literature starting from 1952 (the year in which this sign was described for the first time). We counted 28 cases before ours, thus confirming the exceptional nature of this event.

American Medical Society of Sports Medicine Position Statement: Mononucleosis and Athletic Participation

ABSTRACT

Infectious mononucleosis (IM) is a common illness in children and young adults caused primarily by the Epstein-Barr Virus (EBV). Transmission occurs primarily through sharing oral secretions, thus IM is known as the "kissing disease." Common clinical manifestations include fever, pharyngitis, posterior cervical lymphadenopathy, and splenomegaly. Atypical lymphocytosis and transaminase elevations are common, and the diagnosis of IM is confirmed with laboratory findings of a positive heterophile antibody ("Monospot"), polymerase chain reaction, or antibodies specific to EBV. Individuals with acute IM may be quite symptomatic and not feel well enough to participate in sports. Splenic enlargement is common, with rupture a relatively rare occurrence, typically occurring within a month of symptom onset, but this risk complicates sports participation, and is often the reason for restricting activity. The management of IM is primarily supportive, with no role for antivirals or corticosteroids. The variability of clinical presentation and the risk of splenic rupture in patients with IM present clinicians with challenging return to play/return to sport (RTS) decisions. This position statement updates the Evidence-Based Subject Review on Mononucleosis by the American Medical Society for Sports Medicine published in 2008 and reviews the epidemiology, clinical manifestations, laboratory assessment, and management including RTS for the athlete with IM. This statement also addresses complications, imaging, special considerations, diversity and equity considerations, and areas for future clinical research. Understanding the evidence regarding IM and sport is essential when communicating with athletes and their families and incorporating shared decision-making in the RTS decision.

Fever with atypical lymphocytosis: pearls and pitfalls in Epstein-Barr virus serology

The heterophile antibody (also known as the Monospot) test is a useful screening tool for infectious mononucleosis (IM) resulting from primary Epstein-Barr virus (EBV) infection. However, up to 10% of patients with IM are heterophile negative. Heterophile-negative patients who have lymphocytosis or atypical lymphocytes on peripheral blood smear should be further tested for EBV serologies, which include testing for specific IgM and IgG antibodies against viral capsid antigens, early antigens and EBV nuclear antigen proteins. A diagnostic dilemma arises when the patient has clinical and laboratory features of IM, but is both heterophile negative and seronegative for IM, as illustrated in this case presentation. To avoid missed diagnoses of IM, misdiagnosis of mononucleosis-like illnesses and unnecessary testing, knowledge of test characteristics and the evolving course of EBV serologies is important to assure and inform both the physician and the patient.

Epstein-Barr Virus History and Pathogenesis

Epstein-Barr virus (EBV) is the first identified human oncogenic virus that can establish asymptomatic life-long persistence. It is associated with a large spectrum of diseases, including benign diseases, a number of lymphoid malignancies, and epithelial cancers. EBV can also transform quiescent B lymphocytes into lymphoblastoid cell lines (LCLs) in vitro. Although EBV molecular biology and EBV-related diseases have been continuously investigated for nearly 60 years, the mechanism of viral-mediated transformation, as well as the precise role of EBV in promoting these diseases, remain a major challenge yet to be completely explored. This review will highlight the history of EBV and current advances in EBV-associated diseases, focusing on how this virus provides a paradigm for exploiting the many insights identified through interplay between EBV and its host during oncogenesis, and other related non-malignant disorders.

Derivation and validation of clinical prediction rules for diagnosis of infectious mononucleosis: a prospective cohort study

OBJECTIVES

Infectious mononucleosis (IM) is a clinical syndrome that is characterised by lymphadenopathy, fever and sore throat. Although generally not considered a serious illness, IM can lead to significant loss of time from school or work due to profound fatigue, or the development of chronic illness. This study aimed to derive and externally validate clinical prediction rules (CPRs) for IM caused by Epstein-Barr virus (EBV).

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

328 participants were recruited prospectively for the derivation cohort, from seven university-affiliated student health centres in Ireland. Participants were young adults (17-39 years old, mean age 20.6 years) with sore throat and one other additional symptom suggestive of IM. The validation cohort was a retrospective cohort of 1498 participants from a student health centre at the University of Georgia, USA.

MAIN OUTCOME MEASURES

Regression analyses were used to develop four CPR models, internally validated in the derivation cohort. External validation was carried out in the geographically separate validation cohort.

RESULTS

In the derivation cohort, there were 328 participants, of whom 42 (12.8%) had a positive EBV serology test result. Of 1498 participants in the validation cohort, 243 (16.2%) had positive heterophile antibody tests for IM. Four alternative CPR models were developed and compared. There was moderate discrimination and good calibration for all models. The sparsest CPR included presence of enlarged/tender posterior cervical lymph nodes and presence of exudate on the pharynx. This model had moderate discrimination (area under the receiver operating characteristic curve (AUC): 0.70; 95% CI: 0.62-0.79) and good calibration. On external validation, this model demonstrated reasonable discrimination (AUC: 0.69; 95% CI: 0.67-0.72) and good calibration.

CONCLUSIONS

The alternative CPRs proposed can provide quantitative probability estimates of IM. Used in conjunction with serological testing for atypical lymphocytosis and immunoglobulin testing for viral capsid antigen, CPRs can enhance diagnostic decision-making for IM in community settings.

A young woman with persistent sore throat, Epstein-Barr virus, lymphadenopathy, and aberrant CD4 + CD7- T-cells

A young woman with persistent EBV viremia and lymphocytosis had an abnormal CD4- T cell population with aberrant loss of CD7. She had a diagnosis of chronic active EBV (CAEBV), a lymphoproliferative disorder for which she ultimately required allogeneic hematopoietic stem cell transplantation.

Immune checkpoints in T cells during oncogenic γ-herpesvirus infections

Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) are two persistent oncogenic γ-herpesviruses with an exclusive tropism for humans. They cause cancers of lymphocyte, epithelial and endothelial cell origin, such as Burkitt's and Hodgkin's lymphoma, primary effusion lymphoma, nasopharyngeal carcinoma, and Kaposi sarcoma. Mutations in immune-related genes but also adverse events during immune checkpoint inhibition in cancer patients have revealed molecular requirements for immune control of EBV and KSHV. These include costimulatory and coinhibitory receptors on T cells that are currently explored or already therapeutically targeted in tumor patients. This review discusses these co-receptors and their influence on EBV- and KSHV-associated diseases. The respective studies reveal surprising specificities of some of these receptors for immunity to these tumor viruses, benefits of their blockade for some but not other virus-associated diseases, and that EBV- and KSHV-specific immune control should be monitored during immune checkpoint inhibition to prevent adverse events that might be associated with their reactivation during treatment.

The value of bile acid spectrum in the evaluation of hepatic injury in children with infectious mononucleosis caused by Epstein Barr virus infection

Background

Infectious mononucleosis (IM) is an acute infectious disease, caused by Epstein-Barr virus (EBV) infection, which can invade various systemic systems, among which hepatic injury is the most common. In this study, ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to detect serum bile acid spectrum in IM children quantitatively, and to investigate its role in the early assessment of hepatic injury.

Methods

This case-control study was conducted at Yuhuan People's Hospital. A total of 60 IM children and 30 healthy children were included in the study. Among 60 children with IM, 30 had hepatic injury, and 30 without hepatic injury. The clinical and laboratory data were analyzed, and the serum bile acid spectrum and lymphocyte subsets were evaluated in the three groups.

Results

There were statistically significant differences in cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA), glycochenodeoxycholic acid (GCDCA), glycodeoxycholic acid(GDCA), glycolithocholic acid (GLCA), taurocholic acid (TCA), taurochenodeoxycholic acid (TCDCA), taurodeoxycholic acid (TDCA), ursodeoxycholic acid (UDCA), glycoursodeoxycholic acid (GUDCA), tauroursodeoxycholic acid(TUDCA), percentage of NK cells, CD4+ and CD8+ in IM hepatic injury group, without hepatic injury group, and the healthy control group (P < 0.05). The percentage of NK cells was positively correlated with TCA (P < 0.05); it was negatively correlated with CDCA, DCA, LCA, GCDCA, GDCA, GLCA, TDCA, UDCA, GUDCA, TUDCA (P < 0.05). CD4+ was positively correlated with CA, TCA and TCDCA (P < 0.05); it was negatively correlated with CDCA, DCA, LCA, GCDCA, GDCA, GLCA, TDCA, UDCA, GUDCA and TUDCA (P < 0.05). CD8+ was positively correlated with CDCA, DCA, LCA, GCDCA, GDCA, GLCA, TDCA, UDCA, GUDCA and TUDCA (P < 0.05); it was negatively correlated with CA, TCA and TCDCA (P < 0.05). ROC curve analysis showed that CD8+, GDCA and GLCA had high predictive value for hepatic injury in IM patients.

Conclusions

UPLC-MS/MS method can sensitively detect the changes in serum bile acid spectrum before hepatic injury in children with IM, which is helpful for early assessment of hepatic injury in children with IM. The changes in lymphocyte subsets in IM children are related to some bile acid subfractions, which may be related to IM hepatic injury.

CD137 deficiency because of two novel biallelic TNFRSF9 mutations in a patient presenting with severe EBV-associated lymphoproliferative disease

Objectives

Increasing evidence indicates that some germline genetic mutations that impair pathways required for robust host immune surveillance against EBV infection may result in an extremely high susceptibility to EBV-associated lymphoproliferative disease (EBV⁺ LPD). TNFRSF9 encodes a vital costimulatory molecule that enhances CD8⁺ T-cell proliferation, survival and cytolytic activity. To date, no relevant case resulting from TNFRSF9 heterozygous mutations has been identified.

Methods

Here, we report the first case of CD137 deficiency caused by two novel biallelic heterozygous TNFRSF9 mutations [NM_001561.5: c.208 + 1->AT and c.452C>A (p.T151K)] in a patient presenting with severe EBV⁺ LPD. Immunophenotyping and in vitro assays of lymphocyte function and NK cell activity were performed.

Results

Biallelic TNFRSF9 mutations resulted in markedly reduced or abrogated expression of CD137 on activated T, B and NK cells. CD8⁺ T cells from the patient had impaired activation, reduced expression/release of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), perforin and granzyme B, and diminished cytotoxic activity. Functional experiments identified both variations were hypomorphic mutations and played a contributing role in CD137 deficiency and the development of EBV⁺ LPD.

Conclusion

Our study expands the genetic spectrum and clinical phenotype of patients with CD137 deficiency and provides additional evidence that the TNFRSF9 gene plays a critical role in host immune responses to EBV infection.

Infectious mononucleosis in children and differences in biomarker levels and other features between disease caused by Epstein-Barr virus and other pathogens: a single-center retrospective study in China

Background

Infectious mononucleosis (IM) is a common viral infection that typically presents with fever, pharyngitis and cervical lymphadenopathy. Our aim was to identify the different pathogens causing IM in children admitted to our hospital and to analyze the differences in features of infection with different organisms.

Methods

We retrospectively analyzed the data of children aged 0-17 years admitted to Wuhan Children's Hospital during 2013-2022 with IM. We compared symptoms, physical findings, blood counts, and serum biomarkers between patients with IM due to Epstein-Barr virus (EBV) and IM due to other pathogens.

Results

Among 1480 enrolled children, 1253 (84.66%) had EBV infection, 806 (54.46%) had M. pneumoniae infection, 796 (53.78%) had cytomegalovirus infection, 159 (10.74%) had parvovirus infection, 38 (2.57%) had influenza virus infection, and 25 (1.69%) had adenovirus infection. Receiver operating characteristic curves were used to determine the area under the curve for alanine transaminase (ALT), aspartate transaminase (AST), Alkaline phosphatase (ALP), total bilirubin (TBil), indirect bilirubin (IBil) levels to assess liver damage, and for creatine kinase (CK), CK-MB, and lactate dehydrogenase (LDH) levels to assess myocardial damage. The optimal cutoff values of these biomarkers were then determined. In multivariate analysis, elevated ALT, AST, ALP, TBil, and IBil were independently associated with liver damage, and age <3 years, CK, CK-MB, and LDH with myocardial damage.

Conclusion

Evaluation of biomarkers and pathogen detection may help physicians to take preventive actions to avoid serious complications in children with infectious mononucleosis.

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.

Urgency and necessity of Epstein-Barr virus prophylactic vaccines

Epstein-Barr virus (EBV), a γ-herpesvirus, is the first identified oncogenic virus, which establishes permanent infection in humans. EBV causes infectious mononucleosis and is also tightly linked to many malignant diseases. Various vaccine formulations underwent testing in different animals or in humans. However, none of them was able to prevent EBV infection and no vaccine has been approved to date. Current efforts focus on antigen selection, combination, and design to improve the efficacy of vaccines. EBV glycoproteins such as gH/gL, gp42, and gB show excellent immunogenicity in preclinical studies compared to the previously favored gp350 antigen. Combinations of multiple EBV proteins in various vaccine designs become more attractive approaches considering the complex life cycle and complicated infection mechanisms of EBV. Besides, rationally designed vaccines such as virus-like particles (VLPs) and protein scaffold-based vaccines elicited more potent immune responses than soluble antigens. In addition, humanized mice, rabbits, as well as nonhuman primates that can be infected by EBV significantly aid vaccine development. Innovative vaccine design approaches, including polymer-based nanoparticles, the development of effective adjuvants, and antibody-guided vaccine design, will further enhance the immunogenicity of vaccine candidates. In this review, we will summarize (i) the disease burden caused by EBV and the necessity of developing an EBV vaccine; (ii) previous EBV vaccine studies and available animal models; (iii) future trends of EBV vaccines, including activation of cellular immune responses, novel immunogen design, heterologous prime-boost approach, induction of mucosal immunity, application of nanoparticle delivery system, and modern adjuvant development.

A case of infectious mononucleosis complicated with spontaneous atraumatic splenic rapture caused by Epstein-Barr virus infection

Splenic rupture is the most serious complication of infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) infection, with a mortality rate of over 1 in 10. We reported a case of spontaneous atraumatic splenic rupture secondary to IM in a young man. The patient presented with abdominal pain caused by splenic rupture as the initial symptom. The diagnosis and treatment process went through a series of twists and turns, including the emergency department, general surgery department, and infection department. This case suggests that clinicians should consider the possibility of EBV infection in young patients with spleen rupture without obvious cause to avoid misdiagnosis and missed diagnosis.

Development of infectious mononucleosis as an unusual manifestation of COVID-19

It has generally been reported that patients with COVID-19 show a fever, cough, and/or respiratory failure as the most common clinical symptoms but some have unusual symptoms, such as anosmia, diarrhea, and throat pain. We herein report a 26-year-old woman with chief complaints of lymphadenopathy and a fever. First, she underwent a laboratory examination, which showed a high proportion of atypical lymphocytes (19%) and an increase in hepatic enzyme activities, and was then hospitalized with a diagnosis of infectious mononucleosis (IM). However, the blood examination did not show any increase in anti-Epstein-Barr virus VCM-IgM. Subsequently, she developed tonsillar hypertrophy with purulent plugs. An additional examination for infection of other pathogens revealed positivity only for SARS-CoV-2 in a loop-mediated isothermal amplification (LAMP) test. The patient was transferred to the COVID-19-specific isolation ward, and none of the ward staff, patients, or either of the two otolaryngologists who had directly examined this patient showed positive signs for SARS-CoV-2 in a LAMP test. Consequently, this case suggests that even if patients show clinical symptoms and signs of common diseases for otolaryngologists, such as IM, we should keep in mind the possibility of COVID-19 without arbitrarily assuming that IM is caused by Epstein-Barr virus.

Epstein-Barr Virus Hepatitis Masquerading as Painless Jaundice

Epstein-Barr virus (EBV) infection typically presents with pharyngeal symptoms and subclinical transaminitis. We present a case of a 27-year-old woman with no known past medical history who presented with painless jaundice and dark-colored urine for three days. Her review of systems was negative for fever, sore throat, nausea, vomiting, pruritus, or rash. Her last sexual contact was six months ago with a male partner, and she only drank alcohol socially. Family and surgical history were non-significant. Physical examination revealed 3+ bilateral conjunctival icterus without abdominal tenderness or organomegaly. She had elevated transaminases: alanine transaminase (ALT) of 1287U/L and aspartate aminotransferase of (AST) 1057U/L but her alkaline phosphatase (ALP) was only slightly above normal at 109U/L (normal range 35-104U/L), with a direct hyperbilirubinemia - total bilirubin 9.5mg/dl, direct bilirubin 6.8mg/dl; the abdominal ultrasound revealed non-dilated bile ducts. Hepatitis A, B, and C serology was negative, but her EBV serology showed an infection. She had incidental thalassemia minor without splenomegaly or asterixis. She was managed conservatively, and her liver enzymes trended down with supportive management. Although EBV is an uncommon cause of painless jaundice, this diagnosis should be considered, especially when other more common causes of jaundice have been ruled out. A high index of suspicion should be maintained to detect EBV hepatitis as it can easily be diagnosed through serological testing.

Lemierre’s Syndrome as a Sexually Transmitted Disease Due to Porphyromonas asaccharolytica Suspected to Be Caused by Pharyngitis Due to Mycoplasma pneumoniae and Epstein-Barr Virus

Porphyromonas asaccharolytica rarely causes Lemierre's syndrome (LS), which is characterised by sepsis and thrombophlebitis of the internal jugular vein.

An 18-year-old man presented with fever and a sore throat after sexual contact containing oral sex, and his blood sample was positive for atypical lymphocytes. Infectious mononucleosis was suspected initially. However, laboratory data showed elevated D-dimer and procalcitonin levels, and a computed tomography scan showed a thrombus in the internal jugular vein leading to the diagnosis of LS. The Mycoplasma pneumoniae (MP) IgM titre was 1:640 (normal, ≦1:40), and the Epstein-Barr nuclear antigen titre (taken 59 days after admission) was 1:10 (normal, <1:10). It was assumed that LS developed after infection with Epstein-Barr virus (EBV) and MP.

LS should be suspected in young patients with fever and sore throat with a history of recent sexual contact. As pharyngitis was considered the cause of LS, evaluation of the preceding infection such as MP or EBV leading to pharyngitis should also be considered.

[EBV-associated lymphoproliferative disorders]

Epstein-Barr-virus-associated lymphoproliferations (EBV-LPD) constitute a wide spectrum from benign, self-limiting lymphoproliferations to malignant lymphoma. Because of the clinical and morphological heterogeneity of EBV-LPD and the high prevalence of EBV infections, knowledge of the diagnostic criteria is of great importance for the practice of diagnostic pathology. In this review, clinical and pathological characteristics of the non-malignant EBV-related LPD in patients with and without immunosuppression are presented and their current classification is discussed.EBV-LPD can be of B‑cell or T/NK-cell origin. Identification of EBV latency type and information about possible (iatrogenic) immunodeficiency of the patient are critical for diagnostic evaluation and separation from malignant lymphoma. The clinical context and the detection of EBV in T‑ and NK-cells are both essential for the diagnosis of EBV+ T/NK-cell LPD, which are rare in European countries.

Genomics Driving Diagnosis and Treatment of Inborn Errors of Immunity With Cancer Predisposition

Inborn errors of immunity (IEI) are genetically and clinically heterogeneous disorders that, in addition to infection susceptibility and immune dysregulation, can have an enhanced cancer predisposition. The increasing availability of upfront next-generation sequencing diagnostics in immunology and oncology have uncovered substantial overlap of germline and somatic genetic conditions that can result in immunodeficiency and cancer. However, broad application of unbiased genetics in these neighboring disciplines still needs to be deployed, and joined therapeutic strategies guided by germline and somatic genetic risk factors are lacking. We illustrate the current difficulties encountered in clinical practice, summarize the historical development of pathophysiological concepts of cancer predisposition, and review select genetic, molecular, and cellular mechanisms of well-defined and illustrative disease entities such as DNA repair defects, combined immunodeficiencies with Epstein-Barr virus susceptibility, autoimmune lymphoproliferative syndromes, regulatory T-cell disorders, and defects in cell intrinsic immunity. We review genetic variants that, when present in the germline, cause IEI with cancer predisposition but, when arising as somatic variants, behave as oncogenes and cause specific cancer entities. We finally give examples of small molecular compounds that are developed and studied to target genetically defined cancers but might also proof useful to treat IEI.

[Virus-induced exanthems in returning travellers]

Dermatological diseases are among the most common travel-associated diseases. In particular, viral infections not only with tropical and subtropical pathogens, but also with viruses common in Germany, which are often accompanied by skin rashes and general symptoms, are of great importance. In addition to an accurate travel history and possible risk exposures, epidemiological information on country-specific risks in combination with molecular and serological analyses is helpful in making the correct diagnosis. This article provides an overview of important virus-induced exanthems in returned travellers.