Fusobacterium necrophorum septicemia following Epstein-Barr virus infectious mononucleosis

We report herein a case of a 20-year-old previously healthy man who presented, 25 days after the onset of clinically and serologically confirmed Epstein-Barr virus (EBV) infectious mononucleosis, Fusobacterium necrophorum septicemia. The diagnosis of postanginal septicemia was confirmed by repeated demonstration of fusiform, obligate anaerobic, Gram-negative bacilli in anaerobic blood cultures, identified as F. necrophorum 15 days after admission. This case report aims at underlining the need of taking into consideration the possibility of severe Fusobacterium septicemia in previously healthy patients following EBV infectious mononucleosis in order to prevent increased mortality and morbidity.     

Epstein-Barr virus and cytomegalovirus antibodies in infectious mononucleosis.

A method has been evolved for the demonstration of Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infection in 83 cases of infectious mononucleosis. Serum samples were tested for EBV IgM, anti-VCA IgG, anti-EBNA, CMV IgM and CMV IgG antibodies. An acute-phase sample (or samples) and a convalescence sample were examined in each case, and in 44 cases an additional samples was examined 5-12 months after the illness. Since the different antibodies showed characteristic differences in both titre and persistence, a reliable serodiagnosis has become possible. Acute EBV infection is characterized by the presence of EBV-VCA IgG and EBV IgG antibodies and the lack of anti-EBNA. The latter becomes demonstrable as late as the 4th to 5th month after infection. Mean age of the patients was 19 years. EBV infection was demonstrated in 65%, CMV infection in 18% of the cases. In 12% double infection seemed to be probable.     

T cell cytokine profile during primary Epstein-Barr virus infection (infectious mononucleosis)

Cytokine profiles of CD4+ and CD8+ T-cell subsets were evaluated in 8 patients with infectious mononucleosis (IM). Intracellular detection of cytokines using flow cytometry revealed an expansion of IFN-gamma-expressing CD4+ T cells, and particularly CD8+ T cells, while IL-2 expressing cells were less frequently encountered when compared to healthy controls. Single TNF-alpha-expressing CD4+ and CD8+ T cells were likewise reduced and shifted towards IFN-gamma/TNF-alpha co-production. The predominant pro-inflammatory type 1-biased immune response during IM was emphasized by low frequencies of IL-10 expression in both T cell subsets, although some patients displayed elevated serum levels. Six months later, a decreased, but still elevated IFN-gamma expression within the CD8+ T cell subset, and an increased percentage of IL-2-expressing CD4+ and CD8+ T cells, reaching values shown for controls, were noted. Type 2-associated cytokines such as IL-4 and IL-13, as well as IL-6 and TNF-alpha were not significantly different when compared to controls at study entry and at follow-up. The striking expansion of IFN-gamma-producing CD8+ T cells with rather low expression of IL-10, appears to be a key factor for clinically overt disease, but is nevertheless compatible with successful control of the viral infection.     

Immunity to Epstein-Barr virus in Hodgkin's disease preceded by infectious mononucleosis

A patient who developed Hodgkin''s disease four years after infectious mononucleosis had elevated serum antibody titres to Epstein-Barr virus and delayed hypersensitivity reactions to membrane antigens prepared from fresh autologous spleen, from spleen cells of another Hodgkin''s patient, and from cell lines known to carry the Epstein-Barr virus genome. Additional studies in more lymphoma patients will be needed to determine the significance of the reactivity against tumour and virus-associated antigens which has been documented in this patient.     

Infectious mononucleosis and Epstein-Barr virus

Epstein-Barr virus (EBV) is a gamma-herpesvirus that infects over 90% of the human population worldwide. It is usually transmitted between individuals in saliva, and establishes replicative infection within the oropharynx as well as life-long latent infection of B cells. Primary EBV infection generally occurs during early childhood and is asymptomatic. If delayed until adolescence or later, it can be associated with the clinical syndrome of infectious mononucleosis (also known as glandular fever or 'mono'), an illness characterised by fevers, pharyngitis, lymphadenopathy and malaise. EBV infection is also associated with the development of EBV-associated lymphoid or epithelial cell malignancies in a small proportion of individuals. This review focuses on primary EBV infection in individuals suffering from infectious mononucleosis. It discusses the mechanism by which EBV establishes infection within its human host and the primary immune response that it elicits. It describes the spectrum of clinical disease that can accompany primary infection and summarises studies that are leading to the development of a vaccine designed to prevent infectious mononucleosis.     

Genetic polymorphism of natural Epstein-Barr virus isolates from infectious mononucleosis patients and healthy carriers.

We analyzed Epstein-Barr virus (EBV) genomes from lymphoblastoid cell lines isolated from patients with infectious mononucleosis and from healthy subjects from California, Hawaii, and Hong Kong between 1970 and 1987. Using genetic polymorphism as epidemiological markers, we found that several genotypes of EBV cocirculate in a community and that although most EBV strains isolated from California and Southern China may be differentiated genotypically, there was no specific association between genotype and disease or time of isolation.     

Failure to demonstrate concomitant antibody changes to viral antigens other than Epstein-Barr virus (EBV) during or after infectious mononucleosis

A search for antibody rises to viral antigens other than to Epstein-Barr virus, the causative agent, has been carried out in serial serum samples from 82 patients with infectious mononucleosis (IM). Fourfold or greater rises in titer rarely occurred and did did not cluster in time. No rises occurred to cytomegalovirus, only 1.2 percent to herpes simplex virus, and 8.5 percent to varicella zoster virus. Rises to measles antibody were found in 7.5 percent of patients and to rubella in 10.4 percent; these may represent natural infections or immunizations. A few patients also showed rises to respiratory viruses but there was no apparent connection to IM.     

Dynamic expression of viral and cellular microRNAs in infectious mononucleosis caused by primary Epstein-Barr virus infection in children

Background

Epstein-Barr virus (EBV) was the first virus identified to encode microRNAs (miRNAs). Both of viral and human cellular miRNAs are important in EBV infection. However, the dynamic expression profile of miRNAs during primary EBV infection was unknown. This study aimed to investigate the dynamic expression profile of viral and cellular miRNAs in infectious mononucleosis (IM) caused by primary EBV infection.

Methods

The levels of viral and cellular miRNAs were measured in fifteen pediatric IM patients at three different time-points. Fifteen healthy children who were seropositive for EBV were enrolled in the control group. Relative expression levels of miRNAs were detected by quantitative real-time PCR (qPCR) assay.

Results

EBV-miR-BHRF1-1, 1-2-3P, miR-BART13-1, 19-3p, 11-3P, 12–1, and 16–1 in IM patients of early phase were significantly higher than in healthy children. Most cellular miRNAs of B cells, such as hsa-miR-155-5p, ?34a-5p, ?18b-5p, ?181a-5p, and ?142-5p were up-regulated; while most of cellular miRNAs of CD8?+?T cells, such as hsa-miR-223, ?29c-3p, ?181a, ?200a-3p, miR-155-5p, ?146a, and ?142-5p were down-regulated in IM patients. With disease progression, nearly all of EBV-miRNAs decreased, especially miR-BHRF1, but at a slower rate than EBV DNA loads. Most of the cellular miRNAs of B cells, including hsa-miR-134-5p, ?18b-5p, ?34a-5p, and -196a-5p increased with time. However, most of the cellular miRNAs of CD8?+?T cells, including hsa-let-7a-5p, ?142-3p, ?142-5p, and ?155-5p decreased with time. Additionally, hsa-miR-155-5p of B cells and hsa-miR-18b-5p of CD8+ T cells exhibited a positive correlation with miR-BHRF1-2-5P and miR-BART2-5P (0.96?≤?r?≤?0.99, P?<?0.05). Finally, hsa-miR-181a-5p of B cells had positive correlation with miR-BART4-3p, 4-5P, 16–1, and 22 (0.97?≤?r?≤?0.99, P?<?0.05).

Conclusions

Our study is the first to describe the expression profile of viral and cellular miRNAs in IM caused by primary EBV infection. These results might be the basis of investigating the pathogenic mechanism of EBV-related diseases and bring new insights into their diagnosis and treatment.

     

Circular Epstein-Barr virus genomes of reduced size in a human lymphoid cell line of infectious mononucleosis origin.

Circular Epstein-Barr virus (EBV) DNA molecules have been purified and characterized from a human lymphoid cell line derived from a case of heterophile antibody-positive, blood transfusion-induced infectious mononucleosis, 883L. The circular EBV DNA in three cell lines obtained by transformation of human umbilical cord blood leukocytes with a strain of EBV originally derived from 883L was also studied. As estimated from sedimentation velocity data and electron microscopy, the circular EBV DNA molecules are 10 to 15% smaller than either the circular EBV DNA previously found intracellularly in several other types of EBV-transformed cells or the linear EBV DNA present extracellularly in virus particles. In addition, the EBV-transformed cord blood cell lines studied here differed from other EBV-transformed cells in that integrated virus DNA sequences could not be detected.     

Characterization of thymus-derived lymphocyte subsets in acute Epstein-Barr virus-induced infectious mononucleosis.

Changes in thymus-derived (T) lymphocyte subpopulation numbers were studied in patients with acute and convalescent Epstein-Barr virus (EBV)-induced infectious mononucleosis (LM). T cell subsets were characterized by the presence of Fc receptors for IgG (TG), for IgM (TM) or by the absence of either receptor (Tnon-M, non-G). We found that in acute IM, total numbers of T and B lymphocytes were elevated (p less than 0.01). Of the T lymphocyte subsets, the total number of Tnon-M, non-G lymphocytes was increased six fold compared to normal subjects (p less than 0.001) and included the majority of the atypical T lymphocytes. The number of total TG and TM lymphocytes was moderately increased (p less than 0.05). In convalescent IM patients, the number of total T cells remained slightly elevated (p less than 0.02) whereas proportions and absolute numbers of B lymphocytes and T cell subsets returned to near normal levels. Thus, acute Epstein-Barr virus-induced IM is associated with a T lymphocytosis which is composed predominantly of atypical T cells which lack detectable Fc receptors for IgG or IgM.     

IgM antibodies to Epstein-Barr virus-associated membrane antigen in sera of infectious mononucleosis patients

By the indirect immunofluorescence technique, IgM antibodies to the cell surface of an Epstein-Barr virus (EBV) producer cell line, P3HR-1, were detected in sera from infectious mononucleosis (IM) patients but not in sera from patients with Burkitt lymphoma or nasopharyngeal carcinoma nor in sera from healthy adult donors having antibodies to EBV-specific viral capsid antigen (VCA). Titers of the IgM antibodies were higher in the earlier stages of IM, a pattern similar to that for IgM antibodies to VCA. The IgM antibodies to the cell surface were identified as being those against the EBV-specific membrane antigen (MA) by the following criteria: (1) The antibodies were reactive to MA-positive cell preparations but to MA-negative cell preparations. (2) Titers of the IgM antibodies were not significantly affected after absorption of sera with sheep red blood cells which could completely eliminate heterophil antibodies in the same sera. Detection of the IgM antibodies to MA may have a particular diagnostic value for providing evidence of a recent EBV infection.     

Identification of a novel torque teno mini virus in cerebrospinal fluid from a child with encephalitis

<正>Dear Editor,Anelloviruses,which are all single-strand circular DNA viruses,have extremely heterogeneous genetic features.To date,the family Anelloviridae is divided into 11genus,and the most dominated species include torque teno virus(TTV),torque teno mini virus(TTMV)and     

High viral load in the cerebrospinal fluid and brain correlates with severity of simian immunodeficiency virus encephalitis

AIDS dementia and encephalitis are complications of AIDS occurring most frequently in patients who are immunosuppressed. The simian immunodeficiency virus (SIV) model used in this study was designed to reproducibly induce AIDS in macaques in order to examine the effects of a neurovirulent virus in this context. Pigtailed macaques (Macaca nemestrina) were coinoculated with an immunosuppressive virus (SIV/DeltaB670) and a neurovirulent molecularly cloned virus (SIV/17E-Fr), and more than 90% of the animals developed moderate to severe encephalitis within 6 months of inoculation. Viral load in plasma and cerebrospinal fluid (CSF) was examined longitudinally to onset of AIDS, and viral load was measured in brain tissue at necropsy to examine the relationship of systemic and central nervous system (CNS) viral replication to the development of encephalitis. In all animals, plasma viral load peaked at 10 to 14 days postinfection and remained high throughout infection with no correlation found between plasma viremia and SIV encephalitis. In contrast, persistent high levels of CSF viral RNA after the acute phase of infection correlated with the development of encephalitis. Although high levels of viral RNA were found in the CSF of all macaques (six of six) during the acute phase, this high level was maintained only in macaques developing SIV encephalitis (five of six). Furthermore, the level of both viral RNA and antigen in the brain correlated with the severity of the CNS lesions. The single animal in this group that did not have CNS lesions had no detectable viral RNA in any of the regions of the brain. The results substantiate the use of CSF viral load measurements in the postacute phase of SIV infection as a marker for encephalitis and CNS viral replication.