Immune function in chronic active Epstein-Barr virus infection

Back to the Future? Immunoglobulin Therapy for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

The findings of controlled trials on use of intravenous immunoglobulin G (IV IgG) to treat myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are generally viewed as representing mixed results. On detailed review, a clearer picture emerges, which suggests that the potential therapeutic value of this intervention has been underestimated. Our analysis is consistent with the propositions that: (1) IgG is highly effective for a proportion of patients with severe and well-characterised ME/CFS; (2) responders can be predicted with a high degree of accuracy based on markers of immune dysfunction. Rigorous steps were taken in the research trials to record adverse events, with transient symptom exacerbation commonly experienced in both intervention and placebo control groups, suggesting that this reflected the impact of participation on people with an illness characterised by post-exertional symptom exacerbation. Worsening of certain specific symptoms, notably headache, did occur more commonly with IgG and may have been concomitant to effective treatment, being associated with clinical improvement. The findings emerging from this review are supported by clinical observations relating to treatment of patients with severe and very severe ME/CFS, for whom intramuscular and subcutaneous administration provide alternative options. We conclude that: (1) there is a strong case for this area of research to be revived; (2) pending further research, clinicians would be justified in offering a course of IgG to selected ME/CFS patients at the more severe end of the spectrum. As the majority of trial participants had experienced an acute viral or viral-like onset, we further suggest that IgG treatment may be pertinent to the care of some patients who remain ill following infection with SARS-CoV-2 virus.

Longitudinal associations of lymphocyte subsets with clinical outcomes in chronic fatigue syndrome

Background

Chronic fatigue syndrome (CFS) is characterized by prolonged fatigue and other physical and neurocognitive symptoms. Some studies suggest that CFS is accompanied by disruptions in the number and function of various lymphocytes. However, it is not clear which lymphocytes might influence CFS symptoms.

Purpose

To determine if patient reported fatigue symptoms and physical functioning scores significantly changed across time with lymphocyte counts as evidence of a relation among chronic fatigue symptoms and the immune response.

Methods

The current longitudinal, naturalistic study assessed the cellular expression of three lymphocyte subtypes -- natural killer (NK) cells (CD3-CD16+ and CD3-CD56+) and naïve T cells (CD4+CD45RA+) -- to determine whether changes in lymphocytes at 4 time points across 18 months were associated with clinical outcomes, including CFS symptoms, physical functioning, and vitality, among patients with chronic fatigue.. Latent growth curve models were used to examine the longitudinal relationship between lymphocytes and clinical outcomes.

Results

Ninety-three patients with Fukuda-based CFS and seven with non-CFS fatigue provided study data. Results indicated that higher proportions of naïve T cells and lower proportions of NK cells were associated with worse physical functioning, whereas higher proportions of NK cells (CD3-CD16+) and lower proportions of naïve T cells were associated with fewer CFS symptoms.

Conclusion

These findings suggest that lymphocytes are modestly related to clinical outcomes over time.

Low IFN-gamma production in the first year of life as a predictor of wheeze during childhood

BACKGROUND

Diminished cytokine production in infancy has been associated with an increased risk for allergen sensitization and early-life wheeze.

OBJECTIVE

We sought to assess the effect of low cytokine production in the first year of life on the development of wheeze through age 13 years.

METHODS

Cytokine production (IFN-gamma and IL-2) by mitogen-stimulated mononuclear cells was determined from peripheral blood samples (9.4 months, n = 118) in a subset of healthy infants enrolled in the Tucson Children's Respiratory Study. The occurrence of wheeze during the previous year was ascertained at ages 2, 3, 6, 8, 11, and 13 years by means of questionnaire. Relative risk for wheeze was computed with generalized estimating equations.

RESULTS

The risk of wheezing between 2 and 13 years was significantly higher for subjects with low 9-month IFN-gamma production (relative risk, 2.29; 95% CI, 1.35-3.89) and borderline significant for those with intermediate IFN-gamma production (relative risk, 1.59; 95% CI, 0.95-2.68) compared with those who produced high levels of IFN-gamma (P value for linear association = .002). Nine-month IL-2 production was unrelated to wheeze. In relation to complex wheezing phenotypes, 9-month IFN-gamma production was inversely related to toddler wheeze (occurring only before age 6 years, P = .03) and chronic wheeze (occurring before and after age 6 years, P = .007) but not school-age wheeze (occurring only after age 6 years, P = .06).

CONCLUSION

The results suggest that characteristics of the immune system present during the first year of life can anticipate the likelihood of development of episodes of airway obstruction characterized by wheezing.

CLINICAL IMPLICATIONS

Immune susceptibility to asthma is established very early during postnatal life.

Is human herpesvirus-6 a trigger for chronic fatigue syndrome?

Chronic fatigue syndrome (CFS) is an illness currently defined entirely by a combination of non-specific symptoms. Despite this subjective definition, CFS is associated with objective underlying biological abnormalities, particularly involving the nervous system and immune system. Most studies have found that active infection with human herpesvirus-6 (HHV-6)--a neurotropic, gliotropic and immunotropic virus--is present more often in patients with CFS than in healthy control and disease comparison subjects, yet it is not found in all patients at the time of testing. Moreover, HHV-6 has been associated with many of the neurological and immunological findings in patients with CFS. Finally, CFS, multiple sclerosis and seizure disorders share some clinical and laboratory features and, like CFS, the latter two disorders also are being associated increasingly with active HHV-6 infection. Therefore, it is plausible that active infection with HHV-6 may trigger and perpetuate CFS in a subset of patients.

Chronic fatigue syndrome: a systematic review

OBJECTIVE

A systematic review of the literature about chronic fatigue syndrome (CFS).

METHODS

A search of the Medline database (via Ovid and PubMed) with the key words chronic fatigue syndrome, diagnosis, classification, epidemiology, etiology, physiopathology, metabolism, microbiology, immunology, virology, psychology, drug therapy, rehabilitation, and therapy. The reference lists of each article were examined for additional related articles.

RESULTS

CFS was defined in 1988 by the US Centes for Disease Control and Prevention. The prevalence of chronic fatigue syndrome has ranged from 0.2% to 0.7% in the general population. In 1994, the definition of CFS was revised by Fukuda et al. Despite various research in several topics (e.g. infection, immune systems, neuroendocrinology, autonomic activity, neuromuscular involvement), the pathophysiology remains unknown.

CONCLUSION

CFS, with its various major clinical and functional impacts, should be associated with a "biopsychosocial model". Progressive muscular rehabilitation, combined with behavioral and cognitive treatment, is an essential part of therapy.

Generalized myositis mimicking polymyositis associated with chronic active Epstein-Barr virus infection

BACKGROUND

Chronic generalized myositis has not so far been reported as a complication of chronic active Epstein-Barr virus infection (CAEBV). We encountered three patients with chronic generalized myositis mimicking polymyositis associated with CAEBV.

METHODS

To clarify the pathological character of this myositis, we investigated the distribution, clonality, and the immunophenotype of EBV-infected cells and lymphocytes infiltrating in muscles.

RESULTS

Clinically, two patients showed symmetrical proximal weakness and muscle atrophy as the initial and main symptom. Although the condition resembled polymyositis, they had also lingual and/or orbital myositis. The other patient showed generalized myositis at the late phase of CAEBV. In all of them, immunotherapy was ineffective and prognosis was poor. Intramuscular infiltrating lymphocytes in our patients were mainly CD45RO+, CD3+, CD4-, CD8-, TCR betaF1-, TCR deltaTCS1-, CD56-, CD79a-, CD21-, HLA-DR+, ZEBRA -, LMP1-, and EBER+ T cells. Oligoclonal expansion of EBV-infected T cells was shown in the muscles. However, there were no malignant lymphocytes.

CONCLUSIONS

This new form of myositis must be distinguished from polymyositis and the other conventional forms of myositis. Careful investigation of hidden CAEBV is recommended when patients present with steroid non-responsive chronic progressive generalized myositis, in particular, with lingual or orbital involvement.

Cytokine and other immunologic markers in chronic fatigue syndrome and their relation to neuropsychological factors

The literature is reviewed and data are presented that relate to a model we have developed to account for the perpetuation of the perplexing disorder currently termed chronic fatigue syndrome (CFS). In patients with CFS there is chronic lymphocyte overactivation with cytokine abnormalities that include perturbations in plasma levels of proinflammatory cytokines and decrease in the ratio of Type 1 to Type 2 cytokines produced by lymphocytes in vitro following mitogen stimulation. The initiation of the syndrome is frequently sudden and often follows an acute viral illness. Our model for the subsequent chronicity of this disorder holds that the interaction of psychological factors (distress associated with either CFS-related symptoms or other stressful life events) and the immunologic dysfunction contribute to (a) CFS-related physical symptoms (e.g., perception of fatigue and cognitive difficulties, fever, muscle and joint pain) and increases in illness burden and (b) impaired immune surveillance associated with cytotoxic lymphocytes with resulting activation of latent herpes viruses.

Cytokines and chronic fatigue syndrome

Chronic fatigue syndrome (CFS) patients show evidence of immune activation, as demonstrated by increased numbers of activated T lymphocytes, including cytotoxic T cells, as well as elevated levels of circulating cytokines. Nevertheless, immune cell function of CFS patients is poor, with low natural killer cell cytotoxicity (NKCC), poor lymphocyte response to mitogens in culture, and frequent immunoglobulin deficiencies, most often IgG1 and IgG3. Immune dysfunction in CFS, with predominance of so-called T-helper type 2 and proinflammatory cytokines, can be episodic and associated with either cause or effect of the physiological and psychological function derangement and/or activation of latent viruses or other pathogens. The interplay of these factors can account for the perpetuation of disease with remission/exacerbation cycles. A T-helper type 2 predominance has been seen among Gulf War syndrome patients and this feature may also be present in other related disorders, such as multiple chemical sensitivity. Therapeutic intervention aimed at induction of a more favorable cytokine expression pattern and immune status appears promising.

Chronic fatigue syndrome and fibromyalgia. Dilemmas in diagnosis and clinical management

There has been a resurgence of interest in recent years in both chronic fatigue syndrome and fibromyalgia. These perplexing and common clinical conditions are a source of significant patient morbidity and frame one of the more enduring dilemmas of contemporary Western medical thought, namely the ambiguous interface between mind and body. In this article, the current definitions are reviewed, and a framework for an emerging psychobiological model of these syndromes is presented. These issues are synthesized into a pragmatic approach to clinical management.

Epstein-Barr viral gene expression in B-lymphocytes

The strategy of the Epstein-Barr virus to persist lifelong in the host depends on establishing a reservoir, which cannot be detected by the immune system but allows reactivation of the virus for shedding and transmission to a new host. Epithelial cells and B-cells play a major role in this viral strategy of EBV, since differentiating epithelial tissues were shown to be permissive for lytic replication in vivo, whereas the B-lymphocytes become predominantly latently infected. However, which cells are the reservoir and which the sites of lytic replication are not quite clear. With the technique of reverse transcription, PCR and immunohistochemistry, we demonstrated that the B-cells of the peripheral blood are a major site of virus production during the primary infection during infectious mononucleosis. These permissive B-cells were also detected after convalescence, however, the absence of any lytic transcripts suggested an efficient immunological control very early in the viral lytic cycle. Serological data on reactivation of EBV correlated with the detection of lytic cycle transcripts in the blood and thus demonstrated that the site of virus production during infectious mononucleosis must be different from that of the persistent state. In those cases, where the infection takes a chronic active course, control of lytic replication is insufficient, either on the level of immune surveillance or of viral gene regulation. We have demonstrated a virus strain with a lytic phenotype in an individual suffering chronic active infection. The impaired capability of this virus to immortalise B-cells correlated with an enhanced expression of the lytic switch gene BZLF-1 and down-regulation of latent regulatory genes in the early phase of infection.

Interleukin-1 beta, interleukin-1 receptor antagonist, and soluble interleukin-1 receptor type II secretion in chronic fatigue syndrome

Chronic fatigue syndrome is a condition that affects women in disproportionate numbers, and that is often exacerbated in the premenstrual period and following physical exertion. The signs and symptoms, which include fatigue, myalgia, and low-grade fever, are similar to those experienced by patients infused with cytokines such as interleukin-1. The present study was carried out to test the hypotheses that (1) cellular secretion of interleukin-1 beta (IL-1 beta), interleukin-1 receptor antagonist (IL-1Ra), and soluble interleukin-1 receptor type II (IL-1sRII) is abnormal in female CFS patients compared to age- and activity-matched controls; (2) that these abnormalities may be evident only at certain times in the menstrual cycle; and (3) that physical exertion (stepping up and down on a platform for 15 min) may accentuate differences between these groups. Isolated peripheral blood mononuclear cells from healthy women, but not CFS patients, exhibited significant menstrual cycle-related differences in IL-1 beta secretion that were related to estradiol and progesterone levels (R2 = 0.65, P < 0.01). IL-1Ra secretion for CFS patients was twofold higher than controls during the follicular phase (P = 0.023), but luteal-phase levels were similar between groups. In both phases of the menstrual cycle, IL-1sRII release was significantly higher for CFS patients compared to controls (P = 0.002). The only changes that might be attributable to exertion occurred in the control subjects during the follicular phase, who exhibited an increase in IL-1 beta secretion 48 hr after the stress (P = 0.020). These results suggest that an abnormality exists in IL-1 beta secretion in CFS patients that may be related to altered sensitivity to estradiol and progesterone. Furthermore, the increased release of IL-1Ra and sIL-1RII by cells from CFS patients is consistent with the hypothesis that CFS is associated with chronic, low-level activation of the immune system.

Neuroendocrine correlates of chronic fatigue syndrome: a brief review

Chronic fatigue syndrome remains one of the more perplexing syndromes in contemporary clinical medicine. One approach to understanding this condition has been to acknowledge its similarities to other disorders of clearer pathophysiology. In this review, a rationale for the study of neuroendocrine correlates of chronic fatigue syndrome is presented, based in part on the clinical observation that asthenic or fatigue states share many of the somatic symptom characteristics seen in recognized endocrine disorders. Of additional interest is the observation that psychological symptoms, particularly disturbances in mood and anxiety, are equally prominent in this condition. At this time, several reports have provided replicated evidence of disruptions in the integrity of the hypothalamic-pituitary-adrenal axis in patients with chronic fatigue syndrome. It is notable that the pattern of the alteration in the stress response apparatus is not reminiscent of the well-understood hypercortisolism of melancholic depression but, rather, suggests a sustained inactivation od central nervous system components of this system. Recent work also implicates alterations in central serotonergic tone in the overall pathophysiology of this finding. The implications of these observations are far from clear, but they highlight the fact that, though chronic fatigue syndrome overlaps with the well-described illness category of major depression, these are not identical clinical conditions.

In vitro effects of echinacea and ginseng on natural killer and antibody-dependent cell cytotoxicity in healthy subjects and chronic fatigue syndrome or acquired immunodeficiency syndrome patients

Extracts of Echinacea purpurea and Panax ginseng were evaluated for their capacity to stimulate cellular immune function by peripheral blood mononuclear cells (PBMC) from normal individuals and patients with either the chronic fatigue syndrome or the acquired immunodeficiency syndrome. PBMC isolated on a Ficoll-hypaque density gradient were tested in the presence or absence of varying concentrations of each extract for natural killer (NK) cell activity versus K562 cells and antibody-dependent cellular cytotoxicity (ADCC) against human herpesvirus 6 infected H9 cells. Both echinacea and ginseng, at concentrations > or = 0.1 or 10 micrograms/kg, respectively, significantly enhanced NK-function of all groups. Similarly, the addition of either herb significantly increased ADCC of PBMC from all subject groups. Thus, extracts of Echinacea purpurea and Panax ginseng enhance cellular immune function of PBMC both from normal individuals and patients with depressed cellular immunity.

Fibromyalgia and chronic fatigue syndrome: similarities and differences

CFS and FM are clinical conditions characterized by a variety of nonspecific symptoms including prominent fatigue, myalgia, and sleep disturbances. There are no diagnostic studies or widely accepted, pathogenic, explanatory models for either illness. Despite remarkably different diagnostic criteria, CFS and FM have many demographic and clinical similarities. More specifically, few differences exist in the domains of symptoms, examination findings, laboratory tests, functional status, psychosocial features, and psychiatric disorders. FM appears to represent an additional burden of suffering among those with CFS, however, underscoring the importance of recognizing concurrent CFS and FM. Further clarification of the similarities (and differences) between CFS and FM may be useful in studies of prognosis and help define subsets of patients who may benefit from specific therapeutic interventions.

alpha-Interferon treatment of patients with chronic fatigue syndrome

Thirty patients who fulfilled clinical criteria defined by the CDC for Chronic Fatigue Syndrome were treated with alfa 2a interferon or placebo in a double-blind crossover study. Outcome was evaluated by Natural Killer (NK) cell function, lymphocyte proliferation to mitogens and soluble antigens, CD4/CD8 counts and a 10 item Quality of Life (QOL) survey. Although mean NK function rose from 87.8 +/- 19.6 to 129.3 +/- 20.7 lytic untis (LU; p < .05) with 12 weeks of interferon therapy, there was no significant change in the other immunologic parameters or QOL scores. When the 26 patients who completed the study were stratified according to their baseline NK function and lymphocyte proliferation, 4 groups were identified: 3 patients had normal NK cell function and lymphocyte proliferation when compared to normal, healthy controls, 9 had isolated deficiency in lymphocyte proliferation, 7 had diminished NK function only, and 7 had abnormalities for both parameters. QOL scores were not significantly different for the four groups at baseline. After 12 weeks of interferon therapy, QOL score significantly improved in each of the seven patients with isolated NK cell dysfunction (mean score, 16.3 +/- 7.9) compared to baseline (39.7 +/- 12.1; p < .05). In these patients the mean NK function increased from 35.1 +/- 11.7 to 91.5 +/- 22.7 LU (p < .01). Significant improvement was not recorded for QOL in the other three groups. Thus, therapy with alpha interferon has a significant effect on the QOL of that subgroup of patients with CFS manifesting an isolated decrease in NK function.

Association of interleukin-2 and interferon-gamma production by blood mononuclear cells in infancy with parental allergy skin tests and with subsequent development of atopy

The mechanisms regulating the onset of atopic sensitization in human beings are not yet fully clarified. We assessed the capacity of mitogen-stimulated umbilical and peripheral blood mononuclear cells to produce interferon-gamma (IFN-gamma) and interleukin-2 (IL-2) at birth and at 9 months of age in 159 infants. Mononuclear cell production of both IFN-gamma and IL-2 at 9 months, but not at birth, was found to be inversely related to parental immediate skin test reactivity to seven local aeroallergens. Skin test reactivity at the age of 6 years was also inversely related to IFN-gamma and IL-2 production at 9 months of age. However, no relationship was evident between total serum IgE levels at 6 years and production of these cytokines at 9 months. The proportions of circulating lymphocytes and CD4+ or CD8+ cells were also unrelated to skin test reactivity at the age of 6 years. These data suggest that mechanisms regulating skin test reactivity to inhaled allergens may involve deficient IFN-gamma production, deficient IL-2 production, or both during or preceding the time of initial sensitization and that additional mechanisms are involved in regulating total serum IgE level.

Determination of the antibody binding capacity of lymphocyte membrane antigens by flow cytometry in 58 blood donors

The relative density of lymphocyte CD3, CD4, CD5, CD8, CD20, CD23, CD28, CD38, CD45RA, CD45RO, CD57 and HLA-DR antigens was measured as antibody binding capacity (ABC) in 58 blood donors aged 19-66 years. The group was analysed in order to obtain reference values (percentages and absolute numbers) for routine, quantitative three-colour flow cytometry (FC) tests, and we included around ten males and females for each of the 15 year age intervals. Whole blood was stained (30 min on ice) with FITC, PE or PerCP conjugated MAbs. The analysis was performed with a FACScan equipped with LYSYS II and Paint-a-GatePlus software. The instrument was calibrated daily with QC3, QuickCal (FITC and PE) and Calibrite and monthly with QSC and stained cells (which included also the control for PerCP performance). The ABC was measured with QSC (Flow Cytometry Standards Corporation). The CD4+ lymphocytes expressed significantly more CD3, CD28 and HLA-DR antigens, and less CD45RA antigen than the CD8+ cells (p < 0.0001). A significant decrease with age was observed for CD3 and CD45RA on both CD4+ and CD8+ subsets (p < 0.05). The lymphocytes of women, compared with those of men, showed decreased ABC for CD8, CD20 and CD28 antigens. The results illustrate the necessity for close matching of control with case groups. They also illustrate the possibilities of modern FC methods based on quantitative quality control and three-colour analysis.

Chronic intestinal candidiasis as a possible etiological factor in the chronic fatigue syndrome

The chronic candidiasis syndrome, also known as the Candida-related complex, putatively caused by the overgrowth of Candida albicans in the gastrointestinal tract and secondarily in the genital organs, is briefly described. Patients with this disorder have many of the same symptoms as those with the chronic fatigue syndrome, except for the recurrent flu-like symptoms of the latter disorder. The positive response of a large number of patients with the chronic fatigue syndrome (CFS) to an oral antifungal agent and a diet for intestinal candidiasis has been described by another clinician. There is evidence that Candida albicans infection of the mucous membranes depresses T cell and natural killer (NK) cell function. Similar abnormalities of immune function are found in the CFS. The function of cytotoxic T cells, T helper cells, and NK cells is important in preventing reactivation of infections from Epstein-Barr virus, cytomegalovirus, and other herpesviruses. Reactivation of one or more of these viruses could lead to the expression of the flu-like symptoms in the CFS. Yet the immune dysfunction found in this disorder has been considered the primary underlying causal factor. It is proposed that chronic intestinal candidiasis may be an agent which leads to immune depression in many CFS patients and therefore that it could be a causal factor in CFS.

Psychological and immunological correlates of acute overtraining

Five men undertook two intensive interval training sessions per day for 10 days, followed by 5 days of active recovery. Subjects supplied a venous blood sample and completed a mood-state questionnaire on days 1, 6, 11 and 16 of the study. Performance capabilities were assessed on days 1, 11 and 16 using a timed treadmill test to exhaustion at 18 kmh-1 and 1% grade. These individuals became acutely overtrained as indicated by significant reductions in running performance from day 1 to day 11. The overtrained state was accompanied by severe fatigue, immune system deficits, mood disturbance, physical complaints, sleep difficulties, and reduced appetite. Mood states moved toward baseline during recovery, but feelings of fatigue and immune system deficits persisted throughout the study.

Changed distribution and immune effects of nickel augment viral-induced inflammatory heart lesions in mice

We have used the myocarditic coxsackievirus B3 (CB3) infection in Balb/c mice to investigate immunotoxic effects of a ten-week low-dose (0.002 M) administration of nickel chloride (NiCl2) prior to infection. This dose did not influence CB3-induced mortality. Whole-body autoradiography of [63Ni] during the disease showed the pancreas, lungs and myocardium to be new target organs in this disease. Seven days after the inoculation, impulse counting of these organs showed the infection-induced increase of [63Ni] to be 5-fold (P < 0.01) in the pancreas, 2.2-fold (P < 0.05) in the lungs and 1.3-fold (P < 0.05) in the heart. Nickel tended to increase spleen B- and T-cell activities, but thymocyte activity was unaffected. The activity of spleen natural killer (NK) cells decreased by 30% (P < 0.05), whereas blood-cell activity in fact increased by 51% (P < 0.05). The inflammatory and necrotic lesions in the ventricular myocardium seven days after the inoculation covered 3.31% of the tissue section area in infected control mice. This damage was increased by 43% (to 4.74% of the tissue section area) in nickel-treated mice. The response pattern of lymphocyte subsets in situ in myocardial inflammatory lesions was elucidated by an immune histochemical staining technique. The number of cytotoxic T-cells, helper T-cells and Mac 2+ cells (macrophages) in these lesions decreased by 46% (P < 0.05), 41% (P < 0.05) and 27% (not significant), respectively, with the nickel treatment. The number of helper T-cells was negatively correlated to the size of the inflammatory area (r = -0.529, P < 0.02). The results indicate that nickel may contribute to the progression of target organ pathology in infection-induced diseases of an autoimmune and/or inflammatory character, such as diabetes and myocarditis.

Seasonal symptom variation in patients with chronic fatigue: comparison with major mood disorders

The psychobiology of idiopathic fatigue has received renewed interest in the medical literature in recent years. In order to examine the relation between chronic, idiopathic fatigue and specific subtypes of depressive illness, we characterized the pattern and severity of seasonal symptom variation in 73 patients with chronic, idiopathic fatigue, compared to patients with major depression (n = 55), atypical depression (n = 35), and seasonal affective disorder (n = 16) Fifty of the fatigued subjects also met the specific Centers for Disease Control and Prevention case criteria for chronic fatigue syndrome, though this definition was unable to discriminate a distinct subgroup of patients, based on their seasonality scores alone. As a group, the fatigued subjects reported the lowest levels of symptom seasonality of any of the study groups. Further, even in those fatigued subjects with scores in the range of those seen in patients with seasonal affective disorder, seasonality was not reported to be a subjectively distressing problem. These findings lend support to the idea that although chronic fatigue shares some clinical features with certain mood disorders, they are not the same illnesses. These data are also consistent with the emerging view that chronic fatigue represents a heterogeneously determined clinical condition.

[Chronic fatigue syndrome: a critical review]

The term "chronic fatigue syndrome" (CFS) applies to a condition of unknown aetiology characterized clinically by an association of subjective symptoms, the most constant being an invalidating tiredness. The diagnostic criteria in current use do not permit to isolate an homogeneous subgroup among patients consulting for chronic asthenia. In the present state of research no infectious or immunological cause has been demonstrated conclusively, although a persistent enterovirus or herpesvirus type 6 infection or a state of chronic immune activation seem to play a role in some cases. Patients who fulfill the criteria of CFS present with psychiatric overmorbidity, essentially depressive, and in 50% of the cases with the mental disorders preceding CFS. The various theoretical models linking CFS to psychopathology are discussed, and finally the syndrome is regarded as a social construction reproducing or renovating the neurasthenia of the late 19th century. There is no specific treatment of CFS, but antidepressants, cognitive-behavioural therapy and perhaps certain immuno-modulators can be useful. The future lines of research should endeavour to isolate a subgroup of patients with prolonged asthenia after a recognized episode of infection and to identify the immunological, psychological and behavioral characteristics of this particular group as well as their reciprocal interactions.

Lymphocyte phenotype and function in the chronic fatigue syndrome

Lymphocytes of 18 patients meeting the Centers for Disease Control (CDC) case definition for the chronic fatigue syndrome (CFS), 10 similar, chronically fatigued patients not fully conforming to the CDC case definition, and 17 matched, healthy individuals were studied to determine the presence of abnormalities of peripheral cell phenotype and function. Extensive phenotypic analyses of B- and T-cell subsets, natural killer (NK) cells, and macrophages were performed using single-, dual-, and three-color flow cytometry. Compared to controls, in CFS patients the percentage of CD4 T cells and CD4,CD45RA, or naive T cells, was reduced. The CD4,CD45RO, or memory T-cell, subset was numerically normal but expressed increased levels of adhesion markers (CD29, CD54, and CD58). CFS patient lymphocytes showed reduced proliferative responses to phytohemagglutinin, concanavalin A, and staphylococcal enterotoxin B. Lymphocytes from fatigue patients not meeting the CDC definition showed similar abnormalities. These data indicate that peripheral T cells manifest an increased state of differentiation in CFS and related conditions. This may arise as a consequence of an underlying neuropsychiatric and/or neuroendocrine disorder or because of exposure to antigens or superantigens of an infectious agent.

Plasma and cerebrospinal fluid monoamine metabolism in patients with chronic fatigue syndrome: preliminary findings

The syndrome of chronic fatigue, feverishness, diffuse pains, and other constitutional complaints, often precipitated by an acute infectious illness and aggravated by physical and emotional stressors, has a lengthy history in the medical literature. The Centers for Disease Control (CDC) recently formulated a case definition, renaming the illness "chronic fatigue syndrome." Nevertheless, there remain few biological data that can validate the existence of this syndrome as distinct from a wide variety of other, largely psychiatric disorders, and little understanding of its pathogenesis. In the present study, basal plasma and cerebrospinal fluid levels of the monoamine metabolites, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and homovanillic acid (HVA) were determined in 19 patients meeting CDC research case criteria for chronic fatigue syndrome and in 17 normal individuals. Patients with chronic fatigue syndrome showed a significant reduction in basal plasma levels of MHPG and a significant increase in basal plasma levels of 5-HIAA. Although the functional significance of these findings has not been definitively elucidated, they are compatible with the clinical presentation of a syndrome associated with chronic lethargy and fatigue, and with evidence of persistent immune stimulation, and lend support to the idea that chronic fatigue syndrome represents a clinical entity with potential biological specificity.

Chronic fatigue syndrome: clinical condition associated with immune activation

There is much conflicting immunological and viral data about the causes of chronic fatigue syndrome (CFS); some findings support the notion that CFS may be due to one or more immune disorders that have resulted from exposure to an infectious agent. In the present study, flow cytometry and several different monoclonal antibodies recognising T, B, and natural killer (NK) cell populations as well as activation and cell adhesion antigens were used to study 147 individuals with CFS. Compared with healthy controls, a reduced CD8 suppressor cell population and increased activation markers (CD38, HLA-DR) on CD8 cells were found. The differences were significant (p = 0.01) in patient with major symptoms of the disease. These immunological indices were not observed in 80 healthy individuals, in 22 contacts of CFS patients, or in 43 patients with other diseases. No correlation of these findings in CFS patients with any known human viruses could be detected by serology. The findings suggest that immune activation is associated with many cases of CFS.

Altered cytokine release in peripheral blood mononuclear cell cultures from patients with the chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is an idiopathic illness associated with a variety of immunologic abnormalities. To investigate potential pathogenetic mechanisms, we evaluated serum levels and peripheral blood mononuclear cell (PBMC) production of selected cytokines and immunoglobulins. Serum bioactive transforming growth factor beta (TGF-beta) levels were higher (P less than 0.01) in patients with CFS (290 +/- 46 pg/mL) than in control subjects (104 +/- 18 pg/mL), but levels of other cytokines tested were not different. Lipopolysaccharide-stimulated release of interleukin 1 beta (IL-1 beta), IL-6, and tumor necrosis factor-alpha was increased (P less than 0.05) in PBMC cultures from patients with CFS versus control subjects; enhanced (P less than 0.01) IL-6 release to phytohemagglutinin was also observed. In contrast, TGF-beta release in response to lipopolysaccharide was depressed (P less than 0.01) in PBMC cultures derived from patients with CFS. No differences in IL-2 and IL-4 or immunoglobulin production were observed. The enhanced release of inflammatory cytokines by stimulated PBMC from patients with CFS suggests that these cells are primed for an increased response to immune stimuli. These data also suggest an association between abnormal regulation of TGF-beta production in vivo and in vitro with the immunologic consequence of CFS.

Retroviral sequences related to human T-lymphotropic virus type II in patients with chronic fatigue immune dysfunction syndrome

Chronic fatigue immune dysfunction syndrome (CFIDS) is a recently recognized illness characterized by debilitating fatigue as well as immunological and neurological abnormalities [Straus, S.E. (1988) J. Inf. Dis. 157, 405-412]. Once thought to be caused by Epstein-Barr virus, it is now thought to have a different but unknown etiology. We evaluated 30 adult and pediatric CFIDS patients from six eastern states for the presence of human T-lymphotropic virus (HTLV) types I and II by Western immunoblotting, polymearse chain reaction, and in situ hybridization of blood samples. The majority of patients were positive for HTLV antibodies by Western blotting and for HTLV-II gag sequences by polymerase chain reaction and in situ hybridization. Twenty nonexposure healthy controls were negative in all assays. These data support an association between an HTLV-II-like virus and CFIDS.

Effects of methyl mercury exposure on spleen and blood natural killer (NK) cell activity in the mouse

The effect of 12 weeks of exposure to methyl mercury (MeHg) (3.9 micrograms/g diet) on the immune function was studied in female Balb/c mice. This MeHg dose did not affect body, kidney, liver or spleen weight. Thymus weight and cell number decreased by 22% (P less than 0.05) and 50% (P less than 0.001), respectively. The lymphoproliferative response to T and B cell mitogens, however, tended to increase in both lymphoid organs. Natural killer cell activity was reduced by 44% (P less than 0.01) and 75% (P less than 0.05) in the spleen and blood, respectively. The number of red blood cells increased slightly (12%, P less than 0.05), whereas white blood cell counts were unaffected. These results indicate that MeHg evokes immune suppressive effects on protective cytotoxic capacity that is of major importance in the pathogenesis of several diseases.

A comprehensive immunological analysis in chronic fatigue syndrome

A detailed analysis of cell-mediated and antibody-mediated immunity was performed in 20 CDC-defined patients with chronic fatigue syndrome (CFS) and 20 age- and sex-matched healthy controls. CD3+, CD4+, CD8+, and CD20+ lymphocytes were comparable in two groups. Natural killer cells as defined by CD16, CD56 and CD57 antigens were significantly reduced in CFS. A significant increase in the proportions of CD4+ ICAM 1+ T cells was observed in CFS. Monocytes from CFS displayed increased density (as determined by mean fluorescence channel numbers) of intercellular adhesion molecule 1 (ICAM-1) and lymphocyte function associated antigen 1 (LFA-1), but showed decreased enhancing response to recombinant interferon-gamma in vitro. The lymphocyte DNA synthesis in response to phytohaemoglobulin (PHA), Concanavalin A (Con A) and pokeweed mitogen (PWM) was normal but the response to soluble antigens was significantly reduced. Serum IgM, IgG, IgA, and IgG subclasses were normal. In vivo specific antibody response to pneumococcus vaccine was depressed in CFS. Forty percent of patients showed titres of anti-human herpes virus 6 (anti-HHV-6) antibody higher than that in the controls (greater than or equal to 1/80). These data suggest immunological dysfunction in patients with chronic fatigue syndrome. The significance of these observations is discussed.

A controlled trial of intravenous immunoglobulin G in chronic fatigue syndrome

PURPOSE

Currently, there is no established therapy for chronic fatigue syndrome (CFS), a recently defined illness that has been associated with a variety of immunologic abnormalities. Based on the hypothesis that a chronic viral infection or an immunoregulatory defect is involved in the pathogenesis of CFS, the therapeutic benefit of intravenous immunoglobulin G (IV IgG) was evaluated in a group of patients with CFS. Additionally, serum immunoglobulin concentrations and peripheral blood lymphocyte subset numbers were measured at the outset of the study, and the effect of IV IgG therapy on IgG subclass levels was determined.

PATIENTS AND METHODS

Thirty patients with CFS were enrolled in a double-blind, placebo-controlled trial of IV IgG. The treatment regimen consisted of IV IgG (1 g/kg) or intravenous placebo (1% albumin solution) administered every 30 days for 6 months. Participants completed a self-assessment form prior to each of the six treatments, which was used to measure severity of symptoms, functional status, and health perceptions. Patients were also asked to report adverse experiences defined as worsening of symptoms occurring within 48 hours of each treatment.

RESULTS

Twenty-eight patients completed the trial. At baseline, all 28 patients complained of moderate to severe fatigue, and measures of social functioning and health perceptions showed marked impairment. Low levels of IgG1 were found in 12 (42.9%), and 18 (64.3%) had low levels of IgG3. At the end of the study, no significant therapeutic benefit could be detected in terms of symptom amelioration or improvement in functional status, despite restoration of IgG1 levels to a normal range. Major adverse experiences were observed in 20% of both the IV IgG and placebo groups.

CONCLUSION

The results of this study indicate that IV IgG is unlikely to be of clinical benefit in CFS. In addition to the ongoing need for placebo-controlled trials of candidate therapies for CFS, an expanded research effort is needed to define the etiology and pathogenesis of this disorder.

Chronic fatigue syndrome and the psychiatrist

The number of patients who are identified as having chronic fatigue syndrome (CFS) has increased, and as a result, chronic fatigue syndrome has received widespread attention. Research has demonstrated that cognitive, affective and behavioural symptoms are prominent in CFS. Psychiatrists are therefore being asked to participate in the assessment and management of patients with this syndrome. This paper will provide an overview of the clinical characteristics of CFS and the current empirical findings related to its pathology, and will conclude with a discussion of the management of these patients.

[Chronic fatigue syndrome]

Reports on conditions of chronic fatigue associated with other somatopsychic symptoms after acute viral infections have led to the hypothesis of a "chronic fatigue syndrome" (CFS). Historical disease descriptions, like e.g. "myalgic encephalomyelitits", were updated by means of modern virological diagnostic techniques and data analysis. Several viral agents like enteroviruses, Epstein-Barr virus, Human-Herpesvirus 6 and other herpesviruses have been implicated for possible underlying infections. A preliminary disease definition by the Center for Disease Control (CDC) seeks to provide a rational basis for further etiological studies. In fact, there is growing consensus that the syndrome comprises various separate disease entities and causative agents. Today we can tentatively differentiate a "chronic mononucleosis" after infection with Epstein-Barr virus, an etiologically undetermined "postviral fatigue syndrome" and a fatigue syndrome of the myalgic type after Coxsackie-B virus infection. Furthermore, a valid diagnosis of CFS must be based on the exclusion of defined other diseases and the awareness of dealing with a hypothetical concept. As a result, current knowledge does not yet allow specific therapeutic recommendations.

Natural killer cell activity during measles

Natural killer cells are postulated to play an important role in host anti-viral defences. We measured natural killer cell activity in 30 individuals with acute measles (73 +/- 21 lytic units (LU)/10(7) cells) and 16 individuals with other infectious diseases (149 +/- 95 LU) and found it reduced compared with values for adults (375 +/- 70 LU; P less than 0.001) or children (300 +/- 73 LU, P less than 0.01) without infection. Reduced natural killer cell activity was found in measles patients with (84 +/- 30 LU) and without (55 +/- 18 LU) complications and was present for at least 3 weeks after the onset of the rash. Activity was increased by in vitro exposure of cells to interleukin-2. Depressed natural killer cell activity parallels in time the suppression of other parameters of cell-mediated immunity that occurs during measles.

Immunologic abnormalities in chronic fatigue syndrome

The chronic fatigue syndrome (CFS), formerly known as chronic Epstein-Barr virus syndrome, is a clinical state of some complexity and uncertain etiology. In order to characterize in a comprehensive manner the status of laboratory markers associated with cellular immune function in patients with this syndrome, 30 patients with clinically defined CFS were studied. All of the subjects were found to have multiple abnormalities in these markers. The most consistent immunological abnormality detected among these patients, when compared with normal controls, was low natural killer (NK) cell cytotoxicity. The number of NK cells, as defined by reactivity with monoclonal antibody NKH.1 (CD56), was elevated, but the killing of K562 tumor cells per CD56 cell was significantly diminished. Lymphoproliferative responses after stimulation with phytohemagglutinin and pokeweed mitogen were decreased in most patients when compared with those in normal controls, as was the production of gamma interferon following mitogen stimulation. Lymphocyte phenotypic marker analysis of peripheral blood lymphocytes showed that there were significant differences between patients with CFS and controls. There was an increase in the percentage of suppressor-cytotoxic T lymphocytes, CD8, and a proportionally larger increase in the number of CD8 cells expressing the class II activation marker. Most patients had an elevated number of CD2 cells which expressed the activation marker CDw26. The numbers of CD4 cells and the helper subset of CD4+CD29+ cells in patients with CFS were not different from those in controls. There was, however, a significant decrease in the suppressor inducer subset of CD4+ CD45RA+ cells. The number of B cells, CD20 and CD21, were elevated, as were the numbers of a subset of B cells which coexpressed CD20 and CD5. The patterns of immune marker abnormalities observed was compatible with a chronic viral reactivation syndrome.

Measles associated with coronary arteritis

A two-year-old girl with measles virus (MV) and chronic Epstein-Barr virus (EBV) infection developed lethal coronary aneurysmal arteritis accompanied by giant cell pneumonia, systemic lymphadenitis and hepatosplenomegaly. In her coronary arteries, lungs and aorta, cells containing intranuclear and intracytoplasmic inclusions, including syncytial giant cells, were detected, the presence of MV in the organs being proved by electron microscopic and immunofluorescent studies. Immunopathology further demonstrated MV to be disseminated in almost all organs other than lymph nodes. Clinical diagnosis of chronic EBV infection was established on the basis of persistent high titers of antibodies against capsid and early antigens of EBV and viral presence was confirmed by Southern blot hybridization in a mesenterial lymph node obtained at autopsy. To the best of our knowledge, this is the first description of MV association with coronary aneurysmal arteritis, raising the possibility that measles infection can cause severe vasculitis under immuno-suppressive states, such as that caused by chronic EBV infection.

Low circulating T-helper cells in relapsing multiple myeloma

Peripheral blood T-lymphocyte subsets were studied serially over a 6 year period in 50 patients with monoclonal gammopathy of unknown significance and multiple myeloma. The results were correlated with clinical status as measured by responsiveness to treatment (response vs. relapse). To allow assessment of the effects of treatment per se upon T-lymphocyte subset levels, patients were studied prior to as well as on and off therapy. After adjustment for treatment effects, the significant correlation (P less than 0.001) between low percentages of T4-bearing cells and relapse status persisted in all patients. Following multivariate analysis, beta 2-microglobulin and m-protein values correlated with relapse status, but these correlations were not unexpected since these parameters were often used in association with other clinical and laboratory findings to assess relapse status. The most striking finding of this study was the independent correlation between decreasing percent of T4 levels and increasing probability of relapse (P less than or equal to 0.003). Specifically, in this study the proportion of subjects with T4 levels less than 20% who relapsed was 67% regardless of other parameters. The strength of the correlation between the T4 values and relapse may provide insight into the biology of relapsing myeloma as well as adding a clinically useful test for disease assessment.

Acyclovir treatment of the chronic fatigue syndrome. Lack of efficacy in a placebo-controlled trial

Twenty-seven adults with a diagnosis of the chronic fatigue syndrome were enrolled in a double-blind, placebo-controlled study of acyclovir therapy. The patients had had debilitating fatigue for an average of 6.8 years, accompanied by persisting antibodies to Epstein-Barr virus early antigens (titers greater than or equal to 1:40) or undetectable levels of antibodies to Epstein-Barr virus nuclear antigens (titers less than 1:2) or both. Each course of treatment consisted of intravenous placebo or acyclovir (500 mg per square meter of body-surface area) administered every eight hours for seven days. The same drug was then given orally for 30 days (acyclovir, 800 mg four times daily). There were six-week observation periods before, between, and after the treatments. Three patients had acyclovir-induced nephrotoxicity and were withdrawn from the study. Of the 24 patients who completed the trial, similar numbers improved with acyclovir therapy and with placebo (11 and 10, respectively). Neither acyclovir treatment nor clinical improvement correlated with alterations in laboratory findings, including titers of antibody to Epstein-Barr virus or levels of circulating immune complexes or of leukocyte 2',5'-oligoadenylate synthetase. Subjective improvement correlated with various measures of mood. We conclude that acyclovir, as used in this study, does not ameliorate the chronic fatigue syndrome. We believe that the clinical improvement observed in most patients reflected either spontaneous remission of the syndrome or a placebo effect.

Adrenocortical insufficiency associated with Epstein-Barr virus infection in a patient with the Wiskott-Aldrich syndrome

A 10-year-old boy with the Wiskott-Aldrich syndrome developed adrenocortical insufficiency including typical clinical findings, low s-Na, high s-K, high p-ACTH (640 ng/l), low p-aldosterone (33-39 pmol/l), high p-renin (2300-4200 mIU/l) as well as an abnormal response to an ACTH-stimulation test. The adrenocortical insufficiency developed concomitantly with the occurrence of infectious mononucleosis diagnosed clinically and serologically. Adrenalitis caused by Epstein-Barr virus is suggested as the causative factor.