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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.

A large proportion of patients with infectious mononucleosis (IM) have abnormal liver function tests (LFT) at presentation. There is no guideline regarding the management and follow-up of these patients. Some patients also have abdominal ultrasound (US) due to deranged LFT, the need for this practice is unclear. The aim of this systematic review was to evaluate the evidence base on LFT assessment in IM, time to resolution of derangement, and the role of abdominal US.A systematic search of PubMed, EMBASE and the Cochrane library was done. Two authors independently screened records for eligibility using pre-defined criteria. We included both adult and paediatric populations. Quality assessment of included studies was done.A total of 3924 patients were included from 32 studies, of which LFT values were reported on 2779 patients. A combination of typical clinical features, heterophile antibodies and Epstein-Barr virus-specific antibodies were used to ascertain diagnosis. The following proportion of patients had abnormal LFT: aspartate transaminase (57%); alanine transaminase (62%); alkaline phosphatase (65%); bilirubin (16%); gamma-glutamyltransferase (41%). Reported median (interquartile range) time to resolution of LFT was 8 (6-12) weeks (n = 438). Maximum time to resolution was6 months. Clinical hepatomegaly and splenomegaly were found in 35% and 44% of patients, respectively. Enlarged liver and spleen on US were seen in 16 of 29 and 38 of 38 of patients, respectively. There were no reports of decompensated liver disease.Current evidence questions the need for routine assessment of LFT in immunocompetent patients presenting with IM; serial LFT assessments following initial abnormalities are not required in immunocompetent patients with subclinical derangement of LFT; routine US abdomen in IM to evaluate for derangement of LFT is not required.

INTRODUCTION This study aimed to explore the application value of two laboratory tests in the diagnosis of Epstein-Barr virus-associated infectious mononucleosis (EBV-IM) in children. METHODS From January 2018 to December 2020, 166 patients with EBV-IM were included in this study. Two methods were used in the analysis. The results of both tests were compared and analyzed. RESULTS The age of onset of EBV-IM is mainly distributed in the range of 0-6 years, and no difference by gender is observed. The sensitivity and specificity of EBV testing by PCR were 49.4% and 89.8%, respectively, and the area under the receiver operating characteristic curve (AUC) was 0.714 (0.662-0.762). When using the immunofluorescence method to detect EBV antibodies, the two indices with the highest diagnostic efficacy were low-affinity EBV-CA IgG and EBV-CA IgM, and their AUC values were 0.798 (0.751-0.840) and 0.663 (0.609-0.713), respectively. When combining the two indices for testing, the AUC values of EBV-CA IgM + low-affinity EBV-CA IgG, EBV-DNA + EBV-CA IgM, and EBV-DNA + low-affinity EBV-CA IgG were 0.904(0.867-0.933), 0.768 (0.719-0.812) and 0.963 (0.937-0.981), respectively. The diagnostic efficacy of the combined EBV-DNA + EBV-CA IgM + low-affinity EBV-CA IgG test was optimal compared with that of a single index or the combination of two indices, with an AUC of 0.999 (0.986-1.000) (P < 0.05), sensitivity of 100%, and specificity of 89.8%. CONCLUSIONS The combined immunofluorescence and real-time PCR method has high sensitivity and specificity and good application value in the clinical diagnosis of EBV-IM. This article is protected by copyright. All rights reserved.

Heterophile antibody assays have been used to aid the diagnosis of infectious mononucleosis caused by the Epstein-Barr virus. Seven commercially available assays currently widely utilized in clinical laboratories were compared in this study. Variable performance characteristics and assay times are observed, and these pieces of data may assist clinical laboratories in assay selection and result interpretation.

Epstein-Barr virus (EBV) is a human herpesvirus spread in childhood by contact with saliva. In all populations, the great majority of people are infected by middle age. EBV can cause asymptomatic infection, nonspecific symptoms or, especially in adolescents and young adults, the infectious mononucleosis (IM), characterized by pharyngitis, lymphadenopathy, fatigue, and fever. Two main types of skin rashes, accounted as atypical exanthems, occur in patients with acute IM: a faint erythematous maculopapular eruption of 24-48 hours duration (5-15% of the patients) or a pruritic maculopapular rash in almost all patients receiving ampicillin or amoxicillin. Moreover EBV acute infection has been related to other cutaneous manifestations, such as Gianotti-Crosti syndrome, unilateral laterothoracic exanthem (especially in children), and others. In this study, we reported a case of atypical exanthem with an erythematous-papulovesicular pattern in a 22-year-old female patient with IM and performed a review of the literature of the cutaneous and mucosal eruptions occurring during EBV acute infections.

OBJECTIVE Epidemiological research in multiple sclerosis (MS) has mainly been performed in socioeconomically and ethnically limited populations; influences on MS risk have not been studied in prospectively collected non-White populations. We set out to study the influence of previously described MS risk factors in an ethnically diverse population. METHODS A nested case-control study was created using primary care records of >1 million individuals, >50% of whom identify as Black, Asian, and Minority Ethnic (BAME). MS cases were compared to an age- and sex-matched control cohort (1:4), and to a large unmatched cohort. Odds ratios (ORs) of disease were determined according to exposure of interest, and a multivariate model including all exposures was created. Potential pairwise interactions were considered where both indicated a significant effect. RESULTS A total of 1,344 confirmed MS cases were included. MS OR in blacks aged

Background The diagnostic value of high fluorescent lymphocytes (HFLC) and smudge cells in diseases like sepsis has been confirmed. In this study, we explore the diagnostic value of HFLC and smudge cells for infectious mononucleosis (IM). Methods Sixty‐two IM patients, 67 healthy controls, 84 patients with upper respiratory tract virus infection, and 35 patients with malignant lymphoid diseases were enrolled. The complete blood counts and leukocyte differential counts are tested, and the smudge cells were manually counted. Results The value of HFLC% and smudge cells of the IM group were significantly higher than those of healthy controls and disease controls (p 2/100 nucleated cells, it can show better (AUC = 1.000). When the cutoff value of the HFLC% was 1.2%, it can effectively distinguish IM patients from upper respiratory tract virus infection patients (AUC = 0.934); when smudge cells >16/100 nucleated cells, it also has high differential diagnosis value (AUC = 0.913). In addition, the AUC of the combination HFLC% and smudge cells for the differential diagnosis can be increased to 0.968. The performance value of single HFLC% (AUC = 0.942) for distinguishing IM from malignant lymphoid diseases was better than smudge cells and combine index with the cutoff value of 0.4%. Conclusion HFLC% and smudge cells can be used as effective indicators in the early diagnosis and differential diagnosis of IM., HFLC% can be used for auxiliary diagnosis of IM, thereby saving time and reducing cost of smear and manual classification. HFLC% assists the diagnosis of IM with the following advantages. First, this indicator has high specificity and sensitivity for the diagnosis of IM, which can effectively avoid missed diagnosed. Second, HFLC%, as one of the blood routine indicators, can be obtained directly from the automatic blood analyzer. It does not increase additional economic burdens and manual operations. It has better adaptability and superiority, and can prompt clinical diagnosis and treatment earlier. In addition, when the number of smudge cells in the peripheral blood increases, the doctor should be alert to the possibility of IM.

Summary Chloroquine (CQ) and hydroxychloroquine (HCQ) have been used as antiviral agents for the treatment of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV2) infection. We performed a systematic review to examine whether prior clinical studies that compared the effects of CQ and HCQ to a control for the treatment of non‐SARS‐CoV2 infection supported the use of these agents in the present SARS‐CoV2 outbreak. PubMed, EMBASE, Scopus and Web of Science (PROSPERO CRD42020183429) were searched from inception through 2 April 2020 without language restrictions. Of 1766 retrieved reports, 18 studies met our inclusion criteria, including 17 prospective controlled studies and one retrospective study. CQ or HCQ were compared to control for the treatment of infectious mononucleosis (EBV, n = 4), warts (human papillomavirus, n = 2), chronic HIV infection (n = 6), acute chikungunya infection (n = 1), acute dengue virus infection (n = 2), chronic HCV (n = 2), and as preventive measures for influenza infection (n = 1). Survival was not evaluated in any study. For HIV, the virus that was most investigated, while two early studies suggested HCQ reduced viral levels, four subsequent ones did not, and in two of these CQ or HCQ increased viral levels and reduced CD4 counts. Overall, three studies concluded CQ or HCQ were effective; four concluded further research was needed to assess the treatments' effectiveness; and 11 concluded that treatment was ineffective or potentially harmful. Prior controlled clinical trials with CQ and HCQ for non‐SARS‐CoV2 viral infections do not support these agents' use for the SARS‐CoV2 outbreak.

This study examines EBV strains from transplant patients and patients with IM by sequencing major EBV genes. We also used NGS to detect EBV DNA within total genomic DNA, and to evaluate its genetic variation. Sanger sequencing of major EBV genes was used to compare SNVs from samples taken from transplant patients vs. patients with IM. We sequenced EBV DNA from a healthy EBV-seropositive individual on a HiSeq 2000 instrument. Data were mapped to the EBV reference genomes (AG876 and B95-8). The number of EBNA2 SNVs was higher than for EBNA1 and the other genes sequenced within comparable reference coordinates. For EBNA2, there was a median of 15 SNV among transplant samples compared with 10 among IM samples (p = 0.036). EBNA1 showed little variation between samples. For NGS, we identified 640 and 892 variants at an unadjusted p value of 5 × 10(-8) for AG876 and B95-8 genomes, respectively. We used complementary sequence strategies to examine EBV genetic diversity and its application to transplantation. The results provide the framework for further characterization of EBV strains and related outcomes after organ transplantation.

Background and purpose Infectious mononucleosis (IM) caused by Epstein–Barr virus (EBV) has been associated with increased risk of multiple sclerosis (MS). However, the mechanism linking these pathologies is unclear. Different reports indicate the association of EBV, and recently Mycobacterium avium subsp. paratuberculosis (MAP), with MS. For a better understanding of the role of these pathogens, the host response induced by selected antigenic peptides in subjects with a history of IM that significantly increases the risk of MS was investigated. Methods Both humoral and cell-mediated response against peptides able to induce a specific immune activation in MS patients deriving from lytic and latent EBV antigens BOLF1 305−320 , EBNA1 400−413 , from MAP MAP_4027 18−32 , MAP_0106c 121−132 and from human proteins IRF5 424−434 and MBP 85−98 in subjects with current and past IM were examined. Results EBNA1 and MAP_0106c peptides were able to induce a humoral immune response in subjects with a history of clinical IM in an independent manner. Moreover, these peptides were capable of inducing pro-inflammatory cytokine interferon γ by CD4+ and CD8+ T lymphocytes and interleukin 6 and tumour necrosis factor α by CD14+ monocyte cells. Conclusion Our results highlight that EBV and MAP may be involved independently in the same causal process leading to MS in subjects with a history of IM.

We report the outcome of 30 consecutive patients with Hodgkin disease (HD) who underwent single-unit UCBT. Most (90%) patients had failed previous autologous hematopoietic stem cell transplantation. The conditioning regimens were based on combinations of thiotepa, busulfan, cyclophosphamide or fludarabine, and antithymocyte globulin. The cumulative incidence (CI) of myeloid engraftment was 90% [95% confidence interval (C.I.), 74-98%] with a median of 18 d (range, 10-48). CI of acute graft-versus-host disease (GvHD) grades II-IV was 30% (95% C.I., 17-44%), while the incidence of chronic GVHD was 42% (95% C.I., 23-77%). The non-relapse mortality (NRM) at 100 d and 4 yr was 30% (95% C.I., 13-46%) and 47% (95% C.I., 29-65%), respectively. EBV-related post-transplant lymphoproliferative disease (EBV-PTLD) accounted for more than one-third of transplant-related death, with an estimate incidence of 26% (95% C.I., 9-44). The incidence of relapse at 4 yr was 25% (95% C.I., 9-42%). Four-year event-free survival (EFS) and overall survival (OS) were 28% and 30%, respectively. Despite a high NRM and an unexpected high incidence of EBV-PTLD, UCBT in heavily pretreated HD patients is an option for patients lacking a suitable adult donor, provided the disease is not in refractory relapse.

The T-allele in the single nucleotide polymorphism rs6897932 in the gene encoding the IL-7 receptor α (IL7RA) is associated with reduced risk of autoimmune diseases including multiple sclerosis and also affects the course of HIV infection. Low-grade inflammation (LGI) and self-reported, health-related quality of life (HRQL) are often associated with chronic diseases and widely used in assessing and monitoring health status. The aim of the present study was to evaluate whether the T-allele in rs6897932 is associated with reduced risk of LGI (hsCRP 3-10 mg/L), history of infectious mononucleosis (IM), and HRQL in healthy individuals. A total of 17, 293 healthy Danish individuals from the Danish Blood Donor Study were included in the analyses. We tested rs6897932 as a predictor of LGI, self-reported IM, and HRQL in univariable and multivariable models stratified by sex. No associations between rs6897932 and LGI, self-reported IM or HRQL were found in men or women. This suggests that rs6897932 is not associated with general inflammation, and the reported associations between the T-allele in rs6897932 with several autoimmune diseases may be mediated through effects on a restricted part of the immune system.

In this study, we report the clinical and genetic features of Chinese patients with X-linked lymphoproliferative syndrome (XLP). Male patients with fulminant infectious mononucleosis (FIM), Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) or persistent EBV viremia were enrolled in this study. Direct sequencing was used to detect SH2D1A/XIAP gene mutations. The patients' clinical features were assessed by retrieval of data from medical records. Twenty-one male patients with FIM, EBV-associated HLH or persistent EBV viremia were evaluated. Four patients had SH2D1A mutations, and one patient had an XIAP mutation. All five of these patients had symptoms of HLH and EBV infection. Among the five patients, the youngest one was only 1 month old at onset. One patient exhibited hypogammaglobulinemia. Of four patients evaluated for immunological function, all exhibited reduced CD4/CD8 ratios. Three patients had rapid disease progression and died. One patient received haematopoietic stem cell transplantation and is well. The overall clinical phenotypes of Chinese patients with XLP matched previous reports. For patients with severe EBV-associated HLH, our results indicate the need to examine the possibility of XLP.

We performed a pooled analysis of data on self-reported history of infections in relation to the risk of non-Hodgkin lymphoma (NHL) from 17 case-control studies that included 12,585 cases and 15,416 controls aged 16-96 years at recruitment. Pooled odds ratios (OR) and 95% confidence intervals (95% CI) were estimated in two-stage random-effect or joint fixed-effect models, adjusting for age, sex and study centre. Data from the 2 years before diagnosis (or date of interview for controls) were excluded. A self-reported history of infectious mononucleosis was associated with an excess risk of NHL (OR = 1.26, 95% CI = 1.01-1.57 based on data from 16 studies); study-specific results indicate significant (I(2) = 51%, p = 0.01) heterogeneity. A self-reported history of measles or whooping cough was associated with an approximate 15% reduction in risk. History of other infection was not associated with NHL. We find little clear evidence of an association between NHL risk and infection although the limitations of data based on self-reported medical history (particularly of childhood illness reported by older people) are well recognized.

A role for Epstein Barr virus (EBV) in Hodgkin lymphoma (HL) pathogenesis is supported by the detection of EBV genome in about one-third of HL cases, but is not well defined. We previously reported that an elevated prediagnosis antibody titer against EBV nuclear antigens (EBNA) was the strongest serologic predictor of subsequent HL. For the present analysis, we measured antibody levels against EBNA components EBNA1 and EBNA2 and computed their titer ratio (anti-EBNA1:2) in serum samples from HL cases and healthy siblings. We undertook this analysis to examine whether titer patterns atypical of well-resolved EBV infection, such as an anti-EBNA1:2 ratio ≤ 1.0, simply reflect history of infectious mononucleosis (IM), an HL risk factor, or independently predict HL risk. Participants were selected from a previous population-based case-control study according to their history of IM. We identified 55 EBV-seropositive persons with a history of IM (IM+; 33 HL cases, 22 siblings) and frequency-matched a comparison series of 173 IM history-negative, EBV-seropositive subjects on HL status, gender, age and year of blood draw (IM-; 105 cases, 58 siblings). In multivariate logistic regression models, an anti-EBNA1:2 ratio ≤ 1.0 was significantly more prevalent in HL cases than siblings (odds ratio, 95% confidence interval = 2.43, 1.05-5.65); similar associations were apparent within the IM+ and IM- groups. EBNA antibodies were not significantly associated with IM history in HL cases or siblings. These associations suggest that chronic or more severe EBV infection is a risk factor for HL, independent of IM history.

117 patients with acute or chronic hepatitis, 190 patients with liver cirrhosis, 50 patients with hepatitis following mononucleosis infectiosa, and 114 healthy blood donors were examined for the Australia antigen or hepatitis-associated antigen demonstrated by Blumberg et al. in 1965. The Au-antigen was demonstrated in 45 out of 106 patients with acute viral hepatitis, in 3 out of 6 patients with chronic hepatitis, and in 10 out of 190 patients with liver cirrhosis. Au-antigen was demonstrated in 27 per cent of patients with serum hepatitis. In sera examined within the first two weeks following the onset of the disease, Au-antigen could be demonstrated in 82 per cent of the cases of SH and in 37 per cent of those of IH. In 29 out of 45 Au-antigen-positive patients, a conversion from Au(+) to Au(-) was found during the period of observation and the Au-reaction became negative in the majority of patients 4–5 weeks after the commencement of the disease. The Au-antibody was only demonstrated in one patient (21 weeks after the onset of the disease).

In a study of lymphocyte subpopulations in peripheral blood during infectious mononucleosis the lymphocytosis was found to be of T-cell origin (i.e. E-RFC), while the number of non T lymphocytes (i.e. EA-, EAC-RFC and Smlg + ve cells) was normal in 7 out of 8 patients. Ten patients were tested for the presence of HLA-DR determinants on their B and T cells and not only B lymphocytes but also a great part (31–75 96) of T cells were lysed by the anti HLA-DR testsera, indicating that HLA-DR determinants are expressed on a population of T cells in IM patients. After recovery all patients were retested and showed a normal pattern of HLA-DR typing. This indicates an increase of HLA-DR antigens on T cells or a vigorous proliferation of a small DR-positive T-cell subpopulation during the acute stage of IM.

Regulatory T cells (Treg) provide a balance to immune T cell activation thereby protecting the body from pathogen-induced immunopathology. Several persistent viruses induce Treg that subvert protective immune mechanisms and promote viral persistence. Epstein–Barr virus (EBV) generally infects children subclinically and persists thereafter, but primary infection in early adulthood may cause immunopathological damage manifest as infectious mononucleosis. In this study the role of Treg was investigated in acute infectious mononucleosis and healthy EBV seropositive donors. The proportion of CD4+CD25high T cells in blood from infectious mononucleosis patients was significantly lower than in seropositive donors (P = 0.05). Using the FOXP3 marker for Treg the same frequency and extra-follicular distribution of Treg was noted in infectious mononucleosis and control tonsils. Regulatory cytokines, interleukin (IL)-10 and transforming growth factor (TGF)-β, were significantly raised in infectious mononucleosis compared to seropositive donor plasma (P = 0.0001, P = 0.0004 respectively) although levels of IL-10 peaked earlier in infectious mononucleosis than TGF-β. Previous studies identified EBV latent membrane protein (LMP)-1-induced Treg activity [Marshall et al. (2003): J Immunol 170:6183–6189; Marshall et al. (2007): Brit J Haematol 139:81–89], and in this study a significant reduction in interferon-γ production was found from infectious mononucleosis but not seropositive donor lymphocytes after stimulation with a recall antigen when LMP-1 peptide PRG was added (P = 0.03). It is possible that Treg are important in controlling primary EBV infection to a subclinical level in most cases and that infectious mononucleosis represents a failure of this protective mechanism. J. Med. Virol. 81:870–877, 2009. © 2009 Wiley-Liss, Inc.

A proportion of circulating atypical lymphocytes present during the active phase of infectious mononucleosis has an high rate of H3-thymidine incorporation in vitro, but the relationship between DNA synthesis and mitosis in these elements is unclear. In order to appraise the problem, a series of patients with atypical circulating lymphocytes (cases with virus and bacterial infections, reaction due to massive blood transfusion, drug hypersensitivity, schizophrenia) has been studied. An increase of DNA synthetic activity in vitro has been observed, and an high incidence of spontaneous mitoses was detected by means of direct chromosome preparations, as compared to healthy controls. These observations can be regarded as further evidence of high proliferative potential of atypical lymphocytes.

A case report is given of infectious mononucleosis (IM) accidentally transmitted to a patient by transfusion. The donor, two days after giving 450 ml citrated blood, experienced malaise and IM was diagnosed with a typical clinical and haematological course. The citrated blood was stored for three days before the donation. The transfused patient three weeks later developed a febrile syndrome with general adenopathy and the haematological features of IM. The diagnosis of IM was supported by a positive horse-cell slide-agglutination test (EMNI test).

The bone marrow findings in 5 older adults with infectious mononucleosis or mononucleosis-like illnesses are presented. These individuals were initially considered to have lympho-proliferative disorders which often have similar constitutional signs and symptoms. All had atypical lymphocytosis of the peripheral blood. In addition, there were also abnormalities in the bone marrow. The most common findings included focal collection of lymphocytes and the presence of granulomas. The granulomas were small without caseous necrosis and giant cells were infrequent. This is in contrast to the idea that the bone marrow is normal in infectious mononucleosis and gives support to performing core biopsies as the aspirate smears in these individuals did not demonstrate the focal lymphocytosis or granulomas. Whereas, infectious mononucleosis and mononucleosis-like illness may be uncommon in the older individual, they certainly are not rare and it is important to differentiate these benign disorders from the more serious lymphoproliferative diseases. Heterophil test and/or Epstein Barr titers are important confirmatory tests.

A case of infectious mononucleosis with longstanding thrombocytopenia, not responsive to corticosteroid therapy, is presented. Rapid normalization of the platelet level was revealed by splenectomy. The patient is the fourth known case in which it has been necessary to perform splenectomy. A study made with 51Cr-labelled homologous platelets showed a very short half-life, along with a high spleen/liver ratio of the activity. These examinations have not previously been performed in this condition.

The levels of γG, γA and γM have been determined by the Oudin tube method in 26 male and 19 female patients during the course of I.M. A control group consisting of 32 male and 27 female healthy young adults were also analysed. All classes of immunoglobulins were elevated already during the earliest stage of clinically manifest infectious mononucleosis (I.M.), indicating a long incubation period. The highest levels of γG were observed from 10 to 30 days after onset of fever (average 170 per cent of the normal mean), and a slow return towards normal levels took place. Peak levels for γA (163 per cent) occurred simultaneously, but a somewhat more rapid return to normal levels was evident. Increased levels of γM were a constant feature of acute I.M. and the highest levels (300 per cent) were observed from 1 to 20 days after onset of the illness. During convalescence a rapid return towards normal levels was observed, which seemed to parallel the disappearance of Downey cells. Whereas no sex difference was present among the I.M.-patients γM-levels were higher in the female controls.

Acid phosphatase (AcP) and acid alpha-naphthylacetate esterase (ANAE) were examined in lymphoid cells from 104 patients suffering from various lymphoproliferative disorders and from 8 healthy controls. Enzyme activities were evaluated by means of a scoring system. Scores of AcP and ANAE were higher in normal T cells than non-T cells. In comparison, the activated T cells in infectious mononucleosis showed increased AcP and decreased ANAE reaction. Malignant T lymphoblasts had a distinct granular AcP positivity in contrast to the faint reactivity observed in cALL blasts, whereas ANAE showed negative or weak reaction in both subsets. High scores and distinct staining patterns for both enzymes were found in T CLL and T prolymphocytic leukaemia, clearly different from the weak activities seen in B CLL, B PLL and some B cell lymphomas. The latter, too, could be distinguished by mutual differences in enzyme reactions. High AcP and ANAE scores were also found in hairy cell leukaemia, and the staining patterns together with the tartrate resistance firmly established the diagnosis. Thus, simultaneous determinations of AcP and ANAE can be of great value in the diagnosis of lymphoid malignancies.

The in vitro DNA and RNA synthesis of infectious mononucleosis (I.M.) cells have been studied in four patients. For evaluation, monocytoid, lymphocytoid and plasmocytoid I.M. cells were distinguished. Short-term incubation with H3-thymidine revealed that the DNA synthesis index was highest in plasmocytoid forms with 21 per cent labelling, followed by monocytoid I.M. cells with 7.5 per cent and lymphocytoid I.M. cells with 1.3 per cent uptake. In vitro RNA synthesis was also characterized by most active rates of incorporation of H3-uridine and H3-cytidine in plasmocytoid cell types and a similar drop in the intensity of uptake for the other two forms. The still enigmatic origin and function of these irritation cells of the peripheral blood are emphasized. The rather striking autoradiographic findings of cellular proliferation and active RNA synthesis in these cells reveals properties of immature cells. The previously suggested possibility of intracellular viral synthesis is considered to be rather unlikely from our findings. On the other hand, a relationship to multipotent mononuclear stem cells which today have to be assumed to occur in the peripheral blood of even healthy individuals, is discussed.

Using a trypsin-Giemsa banding procedure, chromosome analysis was performed on blood from 21 consecutive patients hospitalized for infectious mononucleosis. Mitoses were harvested after 2 and 24 h in vitro incubation without PHA and after 48 h with PHA. No abnormalities were seen.

The presence of VCA IgG in the absence of VCA IgM and EBNA-1 IgG antibodies makes classifying EBV infection more difficult as this serological picture can be seen in the case of past infection with EBNA-1 IgG loss or non-appearance, or acute infections with the early disappearance or delayed onset of VCA IgM. The aim of this study was to assess the prevalence of this pattern in 2,422 outpatients with suspected EBV infection examined in 2005-2006, and to interpret its significance by means of immunoblotting. One hundred and seventy-seven (7.3%) of the patients were VCA IgG-positive, VCA IgM-negative and EBNA-1 IgG-negative, 15 of whom (8.5%) presented with heterophile antibodies. Analysis by age class showed that the prevalence of isolated VCA IgG ranged from 4.5% in the subjects aged 1-10 years to 9% in those aged >60 years. Immunoblotting allowed 18.9% of the cases to be classified as acute and 81.1% as past infections, the latter being observed in about 37% of the patients aged less than 10 years and in 100% of those aged >30 years. Therefore, in our case series, the presence of isolated VCA IgG was associated usually with past infection, particularly among adults. In children aged less than 10 years, it was associated mainly with acute infection but as past infection may be present in about one-third of such children, this possibility should not be overlooked.

Investigations of HLA and blood-groups were carried out in 68 patients with infectious mononucleosis comprising all known cases diagnosed within one year in a restricted geographical area of Denmark. The HLA distribution of these patients did not differ significantly from that of controls. Combining the results of the present investigation with two previous studies did not show any significantly different distribution from that of combined control groups. The ABO and Rhesus typing was in accordance with that found in a major Danish control group. However, available studies do not exclude the possibility that HLA-D/DR or still unknown HLA factors may be involved in the susceptibility to mononucleosis.

The frequency of HLA-A, -B and -DR antigens in 48 infectious mononucleosis (IM) patients was studied and the antigen frequencies were compared with those of a local panel. The resulting data do not confirm the association of IM and HLA-B35 as reported in a previous work. A high and significant frequency of blank HLA-DR phenotypes was noticed in the IM population during the acute phase, but HLA-DR phenotypic expression was restored after recovery. This lack of expression could be the result of modified HLA-DR expression on circulating EBV infected B lymphocytes.

Epstein-Barr virus and cytomegalovirus have both been associated with Guillain-Barré syndrome after antibody investigations in several patients. In the teenage female patient in this present report, Guillain-Barré syndrome following infectious mononucleosis was associated with sero-conversion against Epstein-Barr virus but not cytomegalovirus. The findings are consistent with the hypothesis that Epstein-Barr virus might be an etiological agent for the Guillain-Barré syndrome and that infection with cytomegalovirus is not a requisite for the syndrome.

Limited research indicates that public attitudes toward individuals with eating disorders are moderately negative. The present study examined specific forms of stigmatisation attributed to individuals with anorexia nervosa (AN). Eighty female participants recruited from an undergraduate institution completed questionnaires assessing stereotypes, prejudice and discrimination of four target individuals: a woman with AN, depression, schizophrenia and mononucleosis. AN was considered to result more from lack of social support and biological factors than poor living habits. Characteristics attributed to targets were less positive for AN than the targets with schizophrenia and mononucleosis; participants reported greater discomfort interacting with the target with AN compared to the targets with depression and mononucleosis. Having actual contact with an individual with AN related to a positive predicted outcome of and comfort in interacting with the target with AN. Findings support the existence of stigma toward individuals with AN. Future research should examine means of reducing stigma. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.