Epstein-Barr virus infectious mononucleosis

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.

The Impact of Co-Infections for Human Gammaherpesvirus Infection and Associated Pathologies

The two oncogenic human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause significant disease burden, particularly in immunosuppressed individuals. Both viruses display latent and lytic phases of their life cycle with different outcomes for their associated pathologies. The high prevalence of infectious diseases in Sub-Saharan Africa (SSA), particularly HIV/AIDS, tuberculosis, malaria, and more recently, COVID-19, as well as their associated inflammatory responses, could potentially impact either virus' infectious course. However, acute or lytically active EBV and/or KSHV infections often present with symptoms mimicking these predominant diseases leading to misdiagnosis or underdiagnosis of oncogenic herpesvirus-associated pathologies. EBV and/or KSHV infections are generally acquired early in life and remain latent until lytic reactivation is triggered by various stimuli. This review summarizes known associations between infectious agents prevalent in SSA and underlying EBV and/or KSHV infection. While presenting an overview of both viruses' biphasic life cycles, this review aims to highlight the importance of co-infections in the correct identification of risk factors for and diagnoses of EBV- and/or KSHV-associated pathologies, particularly in SSA, where both oncogenic herpesviruses as well as other infectious agents are highly pervasive and can lead to substantial morbidity and mortality.

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.

Microbial dysbiosis in the gut drives systemic autoimmune diseases

Trillions of microbes survive and thrive inside the human body. These tiny creatures are crucial to the development and maturation of our immune system and to maintain gut immune homeostasis. Microbial dysbiosis is the main driver of local inflammatory and autoimmune diseases such as colitis and inflammatory bowel diseases. Dysbiosis in the gut can also drive systemic autoimmune diseases such as type 1 diabetes, rheumatic arthritis, and multiple sclerosis. Gut microbes directly interact with the immune system by multiple mechanisms including modulation of the host microRNAs affecting gene expression at the post-transcriptional level or production of microbial metabolites that interact with cellular receptors such as TLRs and GPCRs. This interaction modulates crucial immune functions such as differentiation of lymphocytes, production of interleukins, or controlling the leakage of inflammatory molecules from the gut to the systemic circulation. In this review, we compile and analyze data to gain insights into the underpinning mechanisms mediating systemic autoimmune diseases. Understanding how gut microbes can trigger or protect from systemic autoimmune diseases is crucial to (1) tackle these diseases through diet or lifestyle modification, (2) develop new microbiome-based therapeutics such as prebiotics or probiotics, (3) identify diagnostic biomarkers to predict disease risk, and (4) observe and intervene with microbial population change with the flare-up of autoimmune responses. Considering the microbiome signature as a crucial player in systemic autoimmune diseases might hold a promise to turn these untreatable diseases into manageable or preventable ones.

Fatal unexpected death due to X-linked lymphoproliferative disease

X-linked lymphoproliferative disease (XLP) is a rare immunodeficiency disease characterized by severe immune disorder and extreme vulnerability to Epstein-Barr virus (EBV) infections. Here we report a 14-month-old Chinese boy presenting with fulminant infectious mononucleosis (FIM) following EBV infection, and died of hepatic failure within one week of disease progression. Postmortem examination revealed icterus, ascites, extensive enlarged mesenteric lymphnodes and hepatosplenomegaly. Histopathological examination showed diffuse proliferation of cytotoxic T lymphoid cells and hemophagocytosis in multiple organs. The family history revealed his brother had died under similar circumstances at 5 five years of age. The cause of death of the boy was ascribed to XLP. To the best of our knowledge, there is few autopsy-confirmed XLP case in the forensic practice. The complicatedmanifestations and systemic pathological changes should be well recognized by clinicians and forensic pathologists.

Epstein Barr Virus and Autoimmune Responses in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease. Infections or infectious reactivation are potential triggers for initiation of autoimmunity and for SLE flares. Epstein-Barr virus (EBV) is gamma herpes virus that has been associated with several autoimmune diseases such as SLE, multiple sclerosis, Sjogren’s syndrome, and systemic sclerosis. In this review, we will discuss the recent advances regarding how EBV may contribute to immune dysregulation, and how these mechanisms may relate to SLE disease progression.

Clinical Characteristics and the Risk Factors of Hepatic Injury in 221 Children With Infectious Mononucleosis

Background: Infectious mononucleosis caused by Epstein-Barr Virus infection is a common acute infectious disease in children. About 40-80% of children with infectious mononucleosis have hepatic injury, and hepatic failure is one of the main causes of death in patients with fatal infectious mononucleosis. Identifying the demographics, presenting clinical characteristics and the risk factors of hepatic injury in infectious mononucleosis children are helpful to remind clinicians which patients are prone to have hepatic damage. Methods: A descriptive, cross-sectional study with a 31-month retrospective review was performed on all infectious mononucleosis children hospitalized in the pediatric department of Fuyang People's Hospital. Demographic data, presenting features, radiology imaging, clinical and laboratory parameters, and clinical outcomes of infectious mononucleosis children were collected. Results: Two-hundred twenty-one infectious mononucleosis inpatients were enrolled, and 43.9% (97/221) patients were considered to have a hepatic injury (defined as alanine amino transaminase > 40 U/L). Compared with patients without hepatic injury, hepatic injury patients were marked with a significantly higher percentage of hepatomegaly (31 vs. 49%), splenomegaly (58 vs. 81%) and palpebral edema (47 vs. 63%), higher age (3.05 ± 2.12 vs. 3.84 ± 2.44), hospitalization days (6.85 ± 2.64 vs. 8.08 ± 2.83), leukocyte (14.24 ± 5.32 vs. 18.53 ± 8.63), lymphocytes (9.48 ± 4.49 vs. 13.80 ± 7.47), the proportion of atypical lymphocytes (0.12 ± 0.07 vs. 0.15 ± 0.08) and aspartate aminotransferase (33.71 ± 10.94 vs. 107.82 ± 93.52). The results of correlation analysis and multiple linear regression analysis indicated that age (OR = 1.185; 95% CI = 1.035-1.357, p = 0.014), female (OR = 2.002, 95% CI: 0.261-0.955, p = 0.036) and splenomegaly (OR = 2.171, 95% CI: 1.018-4.628, p = 0.045) were independent risk factors of hepatic injury. Conclusions: In this study, the hepatic injury was associated with gender, age, and splenomegaly, which improved our understanding of risk factors about hepatic injury among infectious mononucleosis children.

Epstein-Barr Virus Epidemiology, Serology, and Genetic Variability of LMP-1 Oncogene Among Healthy Population: An Update

The Epstein-Barr virus (EBV) is a DNA lymphotropic herpesvirus and the causative agent of infectious mononucleosis. EBV is highly prevalent since it affects more than 90% of individuals worldwide and has been linked to several malignancies including PTLDs, which are one of the most common malignancies following transplantation. Among all the EBV genes, most of the recent investigations focused on studying the LMP-1 oncogene because of its high degree of polymorphism and association with tumorigenic activity. There are two main EBV genotypes, Type 1 and 2, distinguished by the differences in the EBNA-2 gene. Further sub genotyping can be characterized by analyzing the LMP-1 gene variation. The virus primarily transmits through oral secretions and persists as a latent infection in human B-cells. However, it can be transmitted through organ transplantations and blood transfusions. In addition, symptoms of EBV infection are not distinguishable from other viral infections, and therefore, it remains questionable whether there is a need to screen for EBV prior to blood transfusion. Although the process of leukoreduction decreases the viral copies present in the leukocytes, it does not eliminate the risk of EBV transmission through blood products. Here, we provide a review of the EBV epidemiology and the genetic variability of the oncogene LMP-1. Then, we underscore the findings of recent EBV seroprevalence and viremia studies among blood donors as a highly prevalent transfusion transmissible oncovirus.

Sickle Cell Beta-Plus Thalassemia with Subcapsular Hematoma of the Spleen

While splenic complications like hypersplenism, sequestration crisis, and infarction are commonly reported in sickle cell variants like sickle cell beta-plus thalassemia, splenic rupture with hematoma is rare. We present a case of a 32-year-old young male who presented with dull left upper quadrant pain who was found to have multiple subcapsular splenic lacerations and hematoma on abdominal imaging. Hemoglobin electrophoresis confirmed sickle cell beta-plus thalassemia in the patient. There was no history of trauma, and rest of the workup for possible cause of spontaneous rupture of spleen was negative. With the patient refusing splenectomy, he was managed conservatively. Clinicians need to be aware of this rare complication of sickle cell variants.

Steroids for symptom control in infectious mononucleosis

BACKGROUND

Infectious mononucleosis, also known as glandular fever or the kissing disease, is a benign lymphoproliferative disorder. It is a viral infection caused by the Epstein-Barr virus (EBV), a ubiquitous herpes virus that is found in all human societies and cultures. Epidemiological studies show that over 95% of adults worldwide have been infected with EBV. Most cases of symptomatic infectious mononucleosis occur between the ages of 15 and 24 years. It is transmitted through close contact with an EBV shedder, contact with infected saliva or, less commonly, through sexual contact, blood transfusions or by sharing utensils; however, transmission actually occurs less than 10% of the time. Precautions are not needed to prevent transmission because of the high percentage of seropositivity for EBV. Infectious mononucleosis is self-limiting and typically lasts for two to three weeks. Nevertheless, symptoms can last for weeks and occasionally months.Symptoms include fever, lymphadenopathy, pharyngitis, hepatosplenomegaly and fatigue. Symptom relief and rest are commonly recommended treatments. Steroids have been used for their anti-inflammatory effects, but there are no universal criteria for their use.

OBJECTIVES

The objectives of the review were to determine the efficacy and safety of steroid therapy versus placebo, usual care or different drug therapies for symptom control in infectious mononucleosis.

SEARCH METHODS

For this 2015 update we searched the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 7), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register; MEDLINE (January 1966 to August 2015) and EMBASE (January 1974 to August 2015). We also searched trials registries, however we did not identify any new relevant completed or ongoing trials for inclusion. We combined the MEDLINE search with the Cochrane search strategy for identifying randomised controlled trials (RCTs). We adapted the search terms when searching EMBASE.

SELECTION CRITERIA

RCTs comparing the effectiveness of steroids with placebo, usual care, or other interventions for symptom control for people with documented infectious mononucleosis.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

For this 2015 update, we did not identify any new RCTs for inclusion. The previous version of the review included seven trials with a total of 362 participants. Four trials compared the effectiveness of a steroid to placebo for short-term symptom control in glandular fever, one to aspirin, and two trials explored the effects of steroids in conjunction with an antiviral. Heterogeneity between trials prevented a combined analysis.Trials under-reported methodological design features. Three trials did not adequately describe sequence generation for randomisation. Four trials provided adequate details of allocation concealment. All trials were double-blind but four were not specific as to who was blinded. Loss to follow-up was under-reported in four trials, making it difficult to exclude attrition bias. The risk of selective reporting in the included trials was unclear.Across the trials, no benefit was found in 8/10 assessments of health improvement. Two trials found benefit of steroid therapy over placebo in reducing sore throat at 12 hours (eight-day course odds ratio (OR) 21.00, 95% confidence interval (CI) 1.94 to 227.20; one-dose OR 4.20, 95% CI 1.08 to 16.32), but the benefit was not maintained.In combination with an antiviral drug, participants in the steroid group had less pharyngeal discomfort between days two to four (OR 0.31, 95% CI 0.09 to 1.08) compared to placebo. Across the trials the effects on other common symptoms were less clear. Two trials set out to measure safety; they documented no major adverse effects. In two other trials adverse events were reported, including respiratory distress and acute onset of diabetes. However, the association of the events with the steroid is not definite.

AUTHORS' CONCLUSIONS

There is insufficient evidence to the efficacy of steroids for symptom control in infectious mononucleosis. There is a lack of research on the side effects and long-term complications.

EBV epiglottitis: Primary supraglottic viral infection in a pediatric immunocompetent host

In this report we describe a case in which a previously healthy 7 year-old male developed acute epiglottitis secondary to Epstein-Barr virus (EBV) infection. This patient required fiberoptic intubation and ICU stay. We discuss epiglottitis diagnosis and management with EBV as the primary etiologic agent.

A case of spontaneous splenic rupture during chemotherapy for B-cell chronic lymphoid leukemia

Spontaneous splenic rupture is a life-threatening disease and an important differential diagnosis of acute abdomen. Early clinical diagnosis and rapid intervention is required to ensure patient survival. Spontaneous splenic rupture may be induced by hematological, inflammatory or infiltrative diseases affecting the spleen. Splenomegaly may also significantly increase the risk of rupture. Other contributory factors include male, adulthood, rapid growth of the spleen and splenic abscess. Here, we present the case of a 69-year-old man who was undergoing chemotherapy for B-cell chronic lymphoid leukemia. He was admitted to our hospital after he suddenly developed persistent upper abdominal pain. Computed tomography and ultrasonography revealed accumulation of free fluid in and around the spleen. He was diagnosed as having spontaneous splenic rupture and an emergency operation was performed. During the operation, we found a massively enlarged spleen with several capsular tears, and performed a splenectomy. The patient made a good recovery. Pathological examination revealed that the spleen was infiltrated by CD20-, CD5- and CD23-positive lymphoid blasts. We encountered a case of spontaneous splenic rupture in a patient receiving chemotherapy for exacerbating B-cell chronic lymphoid leukemia. In a case of abdominal pain of acute onset in patients with hematological disease, spontaneous splenic rupture should be suspected.

Epidemiologic and clinical characteristics of infectious mononucleosis associated with Epstein-Barr virus infection in children in Beijing, China

BACKGROUND

infectious mononucleosis (IM) is a self-limited disease, but a few cases may have severe complications. This retrospective study was to explore the epidemiologic and clinical characteristics of IM associated with Epstein-Barr virus infection (EBV-IM) in children.

METHODS

hospitalized patients with EBV-IM were enrolled during January 2005 to October 2008 in Beijing Children's Hospital Affi liated to Capital Medical University. All patients were divided into four groups: <1 year (group I), 1 to 3 years (group II), 3 to 6 years (group III), and ≥ 6 years (group IV). The epidemiology and clinical characteristics were compared among the four groups.

RESULTS

totally 418 patients were enrolled, with 245 boys and 173 girls. Fever, lymphadenopathy and pharyngitis were three main manifestations of the patients. The incidences of hepatomegaly, splenomegaly and rash were higher in the patients aged below 6 years, and with age increment the incidences lowered. In contrast, the patients aged <1 year had the lowest incidence of tonsillopharyngitis. The total white blood cell count was higher in the infantile group than in the other groups (P=0.038). The infantile group had significantly lower levels of serum alanine aminotransferase and aspartate aminotransferase than the older groups (P=0.007 and P=0.012 respectively). The percentage of CD4(+) T cell subset decreased and the percentage of CD8(+) T cell subset increased with age increment.

CONCLUSIONS

the incidence of EBV-IM peaked in children at age of 4 to 6 years in Northern China. Most of the patients had the classic triad of fever, lymphadenopathy and pharyngitis. Clinical symptoms, signs, laboratory findings and complications of patients varied with ages.

Plasma cells increased markedly in lymph node in hemophagocytic syndrome: a case report

Introduction

Hemophagocytic syndrome is a rare clinicopathological condition characterized by the activation of the mononuclear phagocyte system, resulting in hemophagocytosis in the reticuloendothelial systems. The pathogenesis of HPS remains unclear.

Case presentation

We report the case of a 20-year-old soldier suffering from HPS. Because of long history fever and no reasons being found, his left groin lymph node and left neck lymph node biopsy were done with two weeks interval. We found a marked increase in plasma cells in left neck lymph node during the course of the disease.

Conclusion

Our result provides a new thought for the researchers to understand the mechanisms responsible for the phagocytosis in HPS.

Stress-related Epstein-Barr virus reactivation

Epstein-Barr virus (EBV) remains latent in 90% of the patients following primary infection. The infection might be reactivated due to various stress factors. We, therefore, examined the levels of stress hormones (epinephrine, norepinephrine and cortisol), viral capsid antigen (VCA) immunoglobulin Ig G, VCA IgM, EBV early antigen IgG, Epstein-Barr nuclear antigen (EBNA) IgG, EBNA IgM antibody screening tests and performed EBV polymerized chain reaction (PCR) test and EBV DNA PCR in 100 draftees on their first day of recruitment and at the end of 1 month. Examination of the initial samples revealed that 94 (94%) subjects previously had EBV infection and 6 (6%) were seronegative. Second samples obtained at the end of first month showed that 7 (7.4%) reactivations occurred in 94 subjects who previously had EBV infection (P < 0.001). Two out of six (33.3%) who were initially seronegative had acute infection (P = 0.289). There was no significant difference between the median values of the levels of stress hormones in the initial and second serum and plasma samples. There was a significant difference between the rates of acute infection and reactivation among subjects with elevated cortisol and epinephrine levels in the second samples compared to subjects with normal levels (P < 0.001). No significant difference was determined between the first and second sample hormone levels of all nine subjects whose EBV-DNA turned positive. Routine examinations might not reveal any specific findings since EBV infection often has an asymptomatic course. EBV reactivations should always be kept in mind in patients subject to such stressful conditions.

Proximal splenic artery embolization in the management of splenic rupture

OBJECTIVE

To report the use of proximal splenic artery embolization for management of spontaneous splenic rupture.

DESIGN

Case report and literature review.

SETTING

A tertiary pediatric critical care unit in a university teaching hospital.

INTERVENTIONS

Proximal splenic artery embolization.

MEASUREMENTS AND MAIN RESULTS

An 8-yr-old boy presented with abdominal pain radiating to the left shoulder 9 days after completing induction chemotherapy for acute lymphoblastic leukemia. Imaging revealed a splenic rupture with parenchymal and subcapsular hematomas, with no evidence of active extravasations. The patient was admitted to the pediatric critical care unit for close hemodynamic monitoring and frequent measurements of hemoglobin. His lowest recorded hemoglobin and hematocrit were 63 g/L and 0.19 L/L, respectively. Posttransfusion of packed red blood cells, he was taken to interventional radiology for proximal splenic artery embolization under moderate sedation. Several coils were successfully placed in the proximal splenic arterial system resulting in a marked reduction of splenic blood flow without disruption of collaterals. The patient recovered well from proximal splenic artery embolization in the pediatric critical care unit and experienced short lasting abdominal pain and fever for 1 day. He was discharged home 4 days after the procedure and follow-up imaging showed resolving hematomas with preserved splenic blood flow.

CONCLUSION

Proximal splenic artery embolization in children may be a safe therapeutic alternative to either conservative or surgical management in spontaneous splenic rupture. Preservation of splenic tissue with a reduced risk of repeated hemorrhage can be obtained with proximal splenic artery embolization.

Fatal non-transplant-related epstein-barr virus-associated atypical lymphoid proliferations in infants and children: a clinicopathologic study

Most Epstein-Barr virus (EBV)-related infections in infants and children are asymptomatic or self-limited mild viral illnesses, but rare cases of a rapidly fatal disorder have been described. Failure of the cellular response to control EBV-related lymphoid proliferation leads to severe disease with multiple complications, including a fatal outcome or development of an EBV-driven, clonal lymphoid neoplasm. In this report we characterize 3 cases of fatal, nontransplant, or immunodeficiency-related EBV infection in very young children with immunophenotypic and molecular evidence of B/natural killer (NK)-T cell clonal expansion. An immunohistochemical staining panel included testing for B-cell antigen (CD20), and T/NK cell antigens including CD2, CD3, CD4, CD8, CD56, CD57, and TIA-1. T-cell and B-cell PCR clonality testing was performed on paraffin tissue specimens to identify clonal populations. The ages of these 3 patients ranged from 22 months to 4 years. Initial clinical presentations included pneumonia, abnormal liver function tests and fever, and lymphadenopathy. The 3 patients died within 17 to 72 days of presentation, and autopsy was performed on 1 patient. All cases demonstrated prominent atypical lymphoid or lymphohistiocytic infiltrates, and necrosis was present in 2 of the 3 cases. The atypical lymphocytes were positive for CD3 (cytoplasmic), CD2, CD8, TIA-1, and CD57 and negative for CD4. We molecularly identified B-cell clones in the 2 tested patients, who also showed evidence of hemophagocytosis. Fatal EBV infection is characterized by a morphologic spectrum with atypical lymphoid infiltrates and variable necrosis. Our molecular studies of these patients suggest a clonally-derived expansive process, most likely driven by EBV infection. Our results also suggest that development of clonality is associated with an aggressive clinical course and may be useful in predicting greater risk for fatal outcome. A high index of suspicion, coupled with appropriate serologic and molecular testing, aids in early recognition and diagnosis of these lymphoproliferative processes.

Spontaneous rupture of the spleen: a rare but important differential of an acute abdomen

Spontaneous rupture of the spleen, although previously documented, is a rare phenomenon. It commonly occurs in a pathologic spleen, usually owing to hematological manifestation. We describe a rare incident of spontaneous splenic rupture presenting to an emergency department as a first manifestation. The purpose of this case report is to highlight the importance of considering spontaneous rupture of the spleen as a rare but important differential of an acute abdomen.

Infectious disease and the collegiate athlete

Collegiate athletes are common reservoirs for infectious disease agents. Specific training regimens, living arrangements, and high-risk behaviors may influence the athlete's risk of contracting a variety of infectious diseases. The sports medicine physician plays an important role in recognizing, appropriately treating, designing prevention strategies for, and making return-to-activity decisions for athletes who have infectious diseases.

Immunodominance of lytic cycle antigens in Epstein-Barr virus-specific CD4+ T cell preparations for therapy

BACKGROUND

Epstein-Barr virus (EBV) is associated with a number of human malignancies. EBV-positive post-transplant lymphoproliferative disease in solid organ and hematopoietic stem cell transplant recipients has been successfully treated by the adoptive transfer of polyclonal EBV-specific T cell lines containing CD4+ and CD8+ T cell components. Although patients receiving T cell preparations with a higher CD4+ T cell proportion show better clinical responses, the specificity of the infused CD4+ component has remained completely unknown.

METHODOLOGY/PRINCIPAL FINDINGS

We generated LCL-stimulated T cell lines from 21 donors according to clinical protocols, and analyzed the antigen specificity of the CD4+ component in EBV-specific T cell preparations using a genetically engineered EBV mutant that is unable to enter the lytic cycle, and recombinantly expressed and purified EBV proteins. Surprisingly, CD4+ T cell lines from acutely and persistently EBV-infected donors consistently responded against EBV lytic cycle antigens and autoantigens, but barely against latent cycle antigens of EBV hitherto considered principal immunotherapeutic targets. Lytic cycle antigens were predominantly derived from structural proteins of the virus presented on MHC II via receptor-mediated uptake of released viral particles, but also included abundant infected cell proteins whose presentation involved intercellular protein transfer. Importantly, presentation of virion antigens was severely impaired by acyclovir treatment of stimulator cells, as currently performed in most clinical protocols.

CONCLUSIONS/SIGNIFICANCE

These results indicate that structural antigens of EBV are the immunodominant targets of CD4+ T cells in LCL-stimulated T cell preparations. These findings add to our understanding of the immune response against this human tumor-virus and have important implications for the improvement of immunotherapeutic strategies against EBV.

Emergence of anti-red blood cell antibodies triggers red cell phagocytosis by activated macrophages in a rabbit model of Epstein-Barr virus-associated hemophagocytic syndrome

Hemophagocytic syndrome (HPS) is a fatal complication frequently associated with viral infections. In childhood HPS, Epstein-Barr virus (EBV) is the major causative agent, and red blood cells (RBCs) are predominantly phagocytosed by macrophages. To investigate the mechanism of RBC phagocytosis triggered by EBV infection, we adopted a rabbit model of EBV-associated HPS previously established by using Herpesvirus papio (HVP). The kinetics of virus-host interaction was studied. Using flow cytometry, we detected the emergence of antibody-coated RBCs, as well as anti-platelet antibodies, at peak virus load period at weeks 3 to 4 after HVP injection, and the titers increased thereafter. The presence of anti-RBCs preceded RBC phagocytosis in tissues and predicted the full-blown development of HPS. The anti-RBC antibodies showed cross-reactivity with Paul-Bunnell heterophile antibodies. Preabsorption of the HVP-infected serum with control RBCs removed the majority of anti-RBC activities and remarkably reduced RBC phagocytosis. The RBC phagocytosis was specifically mediated via an Fc fragment of antibodies in the presence of macrophage activation. Therefore, the emergence of anti-RBC antibodies and the presence of macrophage activation are both essential in the development of HPS. Our observations in this animal model provide a potential mechanism for hemophagocytosis in EBV infection.

Spontaneous Splenic Rupture in Infectious Mononucleosis

Abdominal complaints in patients with infectious mononucleosis should alert the surgeon to the potential, and possibly fatal, risk of splenic rupture. Radiologic evaluation by ultrasonography and computed tomography is indicated for appropriate management. We describe a case in which a diagnosis of splenic rupture occurring spontaneously on a background of infectious mononucleosis was made as a result of a high index of suspicion. The patient was treated conservatively.

Upper airway obstruction in infectious mononucleosis

Patients with infectious mononucleosis caused by the Epstein-Barr virus frequently present to the accident and emergency department. The most common presenting symptoms are fever, fatigue, odynophagia and malaise. Although significant airway compromise is rare and occurs in an estimated 1-3.5% of cases, it may present as a potentially life-threatening situation demanding immediate intervention. We present two such cases and discuss their management.

Large B-cell lymphoma presenting as acute abdominal pain and spontaneous splenic rupture; a case report and review of relevant literature

Background

Spontaneous rupture of the spleen is an uncommon dramatic abdominal emergency that requires immediate diagnosis and prompt surgical treatment to ensure the patients survival. Infections have been cited in most cases involving splenic rupture but are rare in hematological malignancies despite frequent involvement of the spleen.

Methods and Materials

We present a case of a splenic rupture caused by infiltration of B-cell lymphoma. A 43 year old gentleman presented with a 1 day h/o left upper quadrant pain; nausea and vomiting for 2 days with associated dizziness and anorexia. The CT showed abnormal spleen 20 × 11 cm with free fluid in the abdomen and enlarged retroperitoneal LNs. The patient underwent a splenectomy after initial resuscitation and the operative finding was that of a massively enlarged spleen with areas of tumor extruding through the splenic capsule.

Result and conclusion

Although the spleen is often involved in hematological malignancies, splenic rupture is an infrequent occurrence. In a recent literature review 136 cases were of splenic rupture secondary to hematological malignancy were identified. Acute leukemia and non Hodgkin lymphoma were the frequent causes followed by chronic myelogeneous leukemia. Male sex, adulthood, severe splenomegaly and cytoreductive chemotherapy were factors more often associated with splenic rupture. Emergency splenectomy remains the cornerstone treatment for splenic rupture.

We present a case report of a "spontaneous splenic rupture" and discuss the presentation, etiology and treatment options along with discussion of relevant literature

Steroids for symptom control in infectious mononucleosis

BACKGROUND

Glandular fever (infectious mononucleosis) is associated with fatigue, fever, sore throat and swollen lymph nodes. The severity of symptoms can vary. In extreme cases, breathing difficulties because of swelling in the throat and other complications can require hospitalization. The duration of symptoms is also variable; in some instances they can last for months. There are few treatments available. There are no universal criteria for using steroids in glandular fever. While their use is generally reserved for severe complications, there are reports of practitioners treating most symptomatic people with steroids. As glandular fever often affects young people at a time in their studies where they need to be continually productive, the potential duration of the condition is perhaps a key factor in prescribing such a potent drug for symptom control.

OBJECTIVES

To determine the efficacy and safety of steroid therapy for symptom control in glandular fever.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2005); MEDLINE (January 1966 to November 2005); EMBASE (January 1974 to November 2005); and the UK National Research Register (November 2005).

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared the effectiveness for symptom control of a steroid to placebo or to another intervention for people of any age with documented glandular fever were included.

DATA COLLECTION AND ANALYSIS

Authors independently assessed trial inclusion according to predetermined criteria. Results are presented separately for each symptom and, where possible, it was intended to combine results in a meta-analysis.

MAIN RESULTS

Seven trials were included. The diagnosis, steroid regime, outcomes and methodological quality varied between trials. The sample size ranged from 24 to 94. For sore throat the results of two studies suggest a benefit at 12 hours of steroid therapy over placebo; however this benefit was not maintained. The evidence from one trial suggests a longer benefit when the steroid is combined with an antiviral drug. There was evidence from one trial that steroids may improve resolution of fatigue around four weeks; however it is unclear if this is only in combination with an antiviral. Two trials reported severe complications in participants in the steroid group.

AUTHORS' CONCLUSIONS

There is insufficient evidence - the trials were few, heterogeneous and some were of poor quality, to recommend steroid treatment for symptom control in glandular fever. There is also a lack of research on the side effects, potential adverse effects or complications, particularly in the long term.

Control of Epstein-Barr virus infection in vitro by T helper cells specific for virion glycoproteins

Epstein-Barr virus (EBV) establishes lifelong persistent infections in humans by latently infecting B cells, with occasional cycles of reactivation, virus production, and reinfection. Protective immunity against EBV is mediated by T cells, but the role of EBV-specific T helper (Th) cells is still poorly defined. Here, we study the Th response to the EBV lytic cycle proteins BLLF1 (gp350/220), BALF4 (gp110), and BZLF1 and show that glycoprotein-specific Th cells recognize EBV-positive cells directly; surprisingly, a much higher percentage of target cells than those expressing lytic cycle proteins were recognized. Antigen is efficiently transferred to bystander B cells by receptor-mediated uptake of released virions, resulting in recognition of target cells incubated with <1 virion/cell. T cell recognition does not require productive infection and occurs early after virus entry before latency is established. Glycoprotein-specific Th cells are cytolytic and inhibit proliferation of lymphoblastoid cell lines (LCL) and the outgrowth of LCL after infection of primary B cells with EBV. These results establish a novel role for glycoprotein-specific Th cells in the control of EBV infection and identify virion proteins as important immune targets. These findings have implications for the treatment of diseases associated with EBV and potentially other coated viruses infecting MHC class II–positive cells.

Fatal splenic rupture caused by infiltration of adult T cell leukemia cells

The spleen is an immunological organ commonly involved in both hematological and nonhematological diseases. Pathological rupture of the spleen has been described in a variety of diseases affecting the spleen. Infections have been cited in most cases involving splenic rupture, but are rare in hematological malignancies despite frequent involvement of the spleen. The present report describes a fatal case of splenic rupture caused by infiltration of adult T cell leukemia cells and reports the mechanism of splenic rupture. The importance of rapid diagnosis and surgery is emphasized.

Training room management of medical conditions: infectious diseases

Management of infectious diseases in athletes encompasses a wide range of pathogens, clinical presentations, and treatment options. Certain athletic activities and training regimens may predispose athletes to increased risk of contracting infectious diseases, some of which may limit athletic participation and pose the threat of significant morbidity. The sports medicine physician plays an important role as a first line of defense in preventing, recognizing, and appropriately treating infectious diseases in athletes.

Periodontitis lesions are a source of salivary cytomegalovirus and Epstein-Barr virus

AIM

Several herpesvirus species can be detected in periodontal pockets and saliva. This study compared human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) DNA copy counts in periodontitis sites and in whole saliva, and evaluated the potential of periodontal therapy to reduce the salivary level of the two viruses.

MATERIAL AND METHODS

A total of 20 systemically healthy periodontitis patients, 21-56 years of age, participated in the study. All 20 patients were examined at baseline, and seven patients also at 3 months after periodontal therapy. Treatment included oral hygiene instruction, scaling and root planing, and surgery. Clinical parameters were evaluated using established methods. In each patient, virological samples were collected from one periodontal pocket of 6-10 mm probing depth, from the adjacent inflamed periodontal pocket wall, and from unstimulated whole saliva. Relationships between subgingival, gingival tissue and salivary herpesvirus counts were evaluated using Spearman's and Kendall's rank correlation coefficient tests. The 5'-nuclease (TaqMan) real-time polymerase chain reaction (PCR) assay was employed to quantify genomic copies of periodontal HCMV and EBV.

RESULTS

At baseline, the 20 periodontitis patients showed significant positive correlations between gingival tissue and salivary counts of HCMV DNA (p=0.003) and EBV DNA (p=0.045). Periodontal pocket depth was positively correlated with salivary EBV DNA counts (p=0.002). Periodontal therapy reduced average full-mouth periodontal pocket depth from 4.6 mm to 1.4 mm, plaque index from 2.1 to 0.9, and gingival index from 2.1 to 0.4. Following treatment, HCMV DNA counts decreased 37.5 fold in subgingival sites and 64.6 fold in saliva, and EBV DNA counts decreased 5.7 fold in subgingival sites and 12.9 fold in saliva.

CONCLUSIONS

The present study provides compelling evidence of a periodontitis source for salivary HCMV and EBV. The potential of periodontal therapy to decrease herpesvirus salivary counts may help diminish herpesvirus transmission from person to person and herpesvirus-related diseases in exposed individuals. Further research is warranted to determine the relationship between periodontal herpesvirus counts and the risk of viral transmission to close acquaintances.

Therapy of other viral infections: herpes to hepatitis

Over the past several years, there has been an increase in knowledge pertaining to the diagnosis and management strategies for the herpes family (Types 1-8), the pox viruses, mumps, measles, rubella, and parvovirus B19 as well as the viral etiologies of hepatitis. Various antiviral treatments, such as nucleoside analogs and interferon therapy, have been available to reduce the signs and symptoms of these common viral infections. This article summarizes the preferred treatment strategies to be employed for each of the viruses for reducing severity, duration, recurrences (notably in the herpes family), transmission rates, as well as preventive alternatives. The majority of the therapeutic options attenuate the course of disease. Treatment decisions are driven by knowledge of the natural history and often are tailored to incorporate clinical circumstances for individual patients. Promotion of community awareness and the development of vaccines should be emphasized in the battle against these common viruses, particularly the herpes simplex viruses, the pox viruses, and hepatitis B.

Acute infectious mononucleosis and coincidental measles virus infection

BACKGROUND

Both Epstein-Barr and measles viruses (MV) cause immune suppression, and the association of the two viruses is evaluated as life threatening. The cell immune impairment caused by simultaneous Epstein-Barr and measles viral infections was responsible for the complicated course of the disease in all described previously reports and for unfavorable outcomes in most of the cases. Timely diagnosis of coincidental viral infections could be a useful predictor for the clinical course and complications. Diagnosis must be based on an accurate assessment of clinical, hematologic, serologic manifestations and supported by appropriate laboratory methods. Recognizing the infectious etiology of concomitant infections is important for both clinicians and epidemiologists.

OBJECTIVE

To describe a case report of a 20-year-old woman previously vaccinated against measles infected with acute mononucleosis and coincidental measles virus infection.

STUDY DESIGN

The clinical, routine laboratory, as well as serological and virologic findings of this patient were scrutinized. Special emphasis was placed on the use of RT-PCR/PCR for confirming the involvement of both measles virus and Epstein-Barr virus (EBV) in this patient's illness.

RESULTS

Infectious mononucleosis was not suspected at admission to the hospital. The final diagnosis of a concomitant measles virus infection and acute infectious mononucleosis was facilitated using viral serology to detect virus-specific IgG and IgM antibodies and by RT-PCR for the detection of measles virus RNA and EBV DNA from peripheral blood monocyte cells (PBMC).

CONCLUSION

The present report highlights the difficulty of diagnosing two coincidental virus infections on clinical grounds. Serological and molecular laboratory methods, specifically the PCR (RT-PCR) analysis, are found to be useful for confirming the concomitant viral infections and proper identification of the infecting pathogens.

Cyclosporine A effectively inhibits graft-versus-host disease during development of Epstein-Barr virus-infected human B cell lymphoma in SCID mouse

We previously constructed human peripheral blood lymphocyte (hu-PBL)/severe combined immunodeficiency mouse (SCID) chimeras and induced human B-cell lymphomas associated with Epstein-Barr virus (EBV) in SCID mice. However, a number of SCID mice died of graft-versus-host disease (GVHD) during the early experimental course. The aim of this study was to test the efficacy of cyclosporine A (CSA) for prevention of GVHD and to define how CSA inhibits the occurrence of GVHD and the production of soluble interleukin (IL) 2 receptor (sIL-2R) in hu-PBL/SCID mice. No mouse died in the active EBV infection group with CSA administration, while 17 mice in three groups without CSA administration died of GVHD. Mortalities in these three groups were 55.56% (5/9), 30.43% (7/23), and 27.78% (5/18), and the medium life span was 17 days. Over the first 33 days after hu-PBL transplantation, serum level of human sIL-2R in hu-PBL/SCID chimeras was stable in the active EBV infection plus CSA group, while sIL-2R concentration gradually increased in the sera of mice with active EBV infection without CSA administration and peaked at 22 days. Thirty-two mice developed tumors among the 43 surviving SCID mice. There was no significant difference of tumor incidence between the active EBV infection groups with CSA and without CSA administration (P > 0.05). From their morphological and immunohistochemical features, as well as detection of human Alu-sequence and EBV in tumor cells, these EBV-induced tumors were identified as human B-cell lymphomas. Thus, CSA can strikingly inhibit GVHD in hu-PBL/SCID chimeras, and should therefore be effective to establish a stable SCID mouse model of human lymphoma associated with EBV. Treatment with CSA had no effect on the tumor incidence in hu-PBL/SCID chimeras after active EBV infection. Accordingly, serum level of sIL-2R is a valuable indicator of GVHD occurrence in hu-PBL/SCID chimeras.

Coinfection by multiple strains of Epstein-Barr virus in infectious mononucleosis in immunocompetent patients

OBJECTIVE

A molecular study of Epstein-Barr virus (EBV)-induced infectious mononucleosis (IM) was performed. The presence of a 30-bp deletion on the latent membrane protein-1 (LMP-1) oncogene from EBV in Caucasian IM patients was evaluated.

MATERIAL AND METHODS

Peripheral blood mononuclear cells were obtained from 27 IM patients and 18 adenoids, 28 tonsils and 16 EBV-related reactive lymphadenitis specimens were used as controls. DNA isolation, EBV polymerase chain reaction (PCR) and LMP-1 oncogene PCR analysis were performed.

RESULTS

The 30-bp deletion on LMP-1 was identified in 29.6% of IM patients, but was always seen in conjunction with full-length LMP-1. Although the LMP-1-deleted strain seemed to be more prevalent in IM (29.6%) and EBV-related reactive lymphadenitis (37.5%,) than in adenoid (0%) or tonsil specimens (21.4%), these differences were not significant (p > 0.05; chi2). Thus, a 30-bp deletion on LMP-1 was present in almost a third of Caucasian IM patients.

CONCLUSION

The finding of coinfections in IM patients confirms that primary infection by more than one EBV strain is possible.

Compartmentalization and transmission of multiple epstein-barr virus strains in asymptomatic carriers

Infection with the Epstein-Barr virus (EBV) is often subclinical in the presence of a healthy immune response; thus, asymptomatic infection is largely uncharacterized. This study analyzed the nature of EBV infection in 20 asymptomatic immunocompetent hosts over time through the identification of EBV strain variants in the peripheral blood and oral cavity. A heteroduplex tracking assay specific for the EBV gene LMP1 precisely identified the presence of multiple EBV strains in each subject. The strains present in the peripheral blood and oral cavity were often completely discordant, indicating the existence of distinct infections, and the strains present and their relative abundance changed considerably between time points. The possible transmission of strains between the oral cavity and peripheral blood compartments could be tracked within subjects, suggesting that reactivation in the oral cavity and subsequent reinfection of B lymphocytes that reenter the periphery contribute to the maintenance of persistence. In addition, distinct virus strains persisted in the oral cavity over many time points, suggesting an important role for epithelial cells in the maintenance of persistence. Asymptomatic individuals without tonsillar tissue, which is believed to be an important source of virus for the oral cavity, also exhibited multiple strains and a cyclic pattern of transmission between compartments. This study revealed that the majority of patients with infectious mononucleosis were infected with multiple strains of EBV that were also compartmentalized, suggesting that primary infection involves the transmission of multiple strains. Both the primary and carrier states of infection with EBV are more complex than previously thought.

Florid infectious mononucleosis: clinicopathological correlation in acute tonsillectomy

In patients with infectious mononucleosis (IM), acute tonsillectomy is advocated only in the minority who develop severe airway compromise. In such florid cases, the pathological diagnosis of IM, well known to morphologically simulate that of lymphoma, is particularly challenging. The present case describes a 15-year old male with a clinical course consistent with IM in whom acute tonsillectomy was performed due to progressive airway obstruction. The striking histological findings emphasize the need for close clinicopathological correlation. Recently available ancillary studies are described which both surgeon and pathologist should be familiar with in the differentiation of IM from other lymphoproliferative conditions.