Natural killer cells and the post viral fatigue syndrome

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.

Immunologic parameters in chronic fatigue syndrome, major depression, and multiple sclerosis

The purpose of this study was to evaluate the immune dysfunction hypothesis of chronic fatigue syndrome (CFS) by comparing immunologic data from patients with CFS with data from patients with other fatiguing illnesses--major depression and multiple sclerosis (MS)--and with data from healthy sedentary controls. The subjects were 65 healthy sedentary controls, 71 CFS patients (41 with no axis-I diagnosis), 23 patients with mild MS, and 21 patients with major depression. Blood was sampled and assayed for the following: (1) immunologic serologic variables--circulating immune complexes (i.e., Raji cell and C1q binding), immunoglobulins A, E, G, and M, and IgG subclasses; (2) cell surface activation markers--the proportion of CD4+ cells expressing CD45RA+ and CD45RO+ and the proportion of CD8+ cells expressing CD38+, CD11b-, HLA-DR+ and CD28+; and (3) natural killer (NK) total cell count as well as the proportion of lymphocytes expressing NK cell surface markers (i.e., CD3-/CD16+ and CD56+. Of the 18 variables studied, differences between CFS patients and controls were found only for IgG1 and IgG3. When CFS patients were stratified by the presence or absence of concurrent axis-I disease, it was the group with axis-I disorder that had the lowest IgG1 values-contrary to expectation. When data from patients with MS and major depression were also evaluated, the subclass deficiency was no longer significant. The one group to show evidence for immune activation (i.e., an elevated proportion of CD4+ cells expressing the CD45RA+ activation marker) was the group with mild MS. These data support neither immune dysfunction nor immune activation in CFS or in major depression, for the variables studied. The reductions in IgG subclasses may be an epiphenomenon of patient or control subject composition. In contrast, MS, even in the mild and early stages, as in the patients studied here, is associated with immune activation.

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.

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.

Electron microscopic immunocytological profiles in chronic fatigue syndrome

Structures consistent in size, shape and character with various stages of a Lentivirus replicative cycle were observed by electron microscopy in 12-day peripheral-blood lymphocyte cultures from 10 of 17 Chronic Fatigue Syndrome patients and not in controls. Attempts to identify a lymphoid phenotype containing these structures by immunogold labelling failed and the results of reverse-transcriptase assay of culture supernatants were equivocal. The study was blind and case-controlled, patients being paired with age, sex and ethnically matched healthy volunteers. Prescreening of subjects included the common metabolic and immunological disorders, functional conditions and a virus-screen against hepatitis B and C, Epstein-Barr Virus, Cytomegalovirus and Human Immunodeficiency Virus.

A clinical study of chronic fatigue syndrome

BACKGROUND

This study examines the hypothesis that more recently ill patients with chronic fatigue syndrome (CFS) might have different characteristics from more chronic patients in tertiary referral centres.

METHOD

Sixty-four patients who fulfilled strict diagnostic criteria for CFS had detailed medical, viral, immunological and psychiatric assessment. Patients were advised to remain within their energy limits. Patient and doctor monitored progress using a scoring system.

RESULTS

Using the Schedule for Affective Disorders and Schizophrenia, patients were placed into four groups: group A (no psychiatric disorder, 35 patients), group B (psychiatric disorder before onset of CFS, 7 patients), group C (coincident psychiatric disorder and CFS, 11 patients), and group D (psychiatric disorder after onset of CFS, 11 patients). There were no viral or immunological differences between the groups. Patients in groups B, C and D had more severe illness than those in group A (P < 0.05), but patients in group A had more muscle pain (P < 0.05) than patients in group C. Counselling resulted in 52 patients becoming better; nine remained the same and three became worse.

CONCLUSIONS

A lower incidence of psychiatric disorder may characterise patients who are more recently ill, as may the type of associated emotional disorder and better outcome.

The haematological, biochemical and immunological profile of athletes suffering from the overtraining syndrome

To help clarify the overtraining syndrome (OTS), a combination of parameters were measured in ten athletes who were suffering from OTS. Blood samples were obtained at rest and a range of haematological, biochemical and immunological tests were carried out on the samples. For each parameter, the mean value for the group was compared to an established normal range amongst age-matched controls. The subjects were also asked to complete a questionnaire to establish the severity of their condition. The data indicated that the debilitating fatigue experienced by the OTS sufferers was not related to any of the blood parameters traditionally associated with chronic exercise stress, since levels were normal in OTS. The only parameter measured which deviated significantly from the normal range for both the sedentary controls and the athletes was the plasma concentration of glutamine. Although the data in this study would suggest that plasma glutamine concentrations represented an objective, measurable difference between OTS subjects and normal controls, it remains to be shown that there is any correlation between glutamine concentrations and other clinical symptoms of OTS such as physical capability.

Eicosanoids and essential fatty acid modulation in chronic disease and the chronic fatigue syndrome

Abnormalities of Essential Fatty Acid (EFA) incorporation into phospholipid are found in chronic diseases. More recently changes in circulating EFA metabolites (EFAM) together with EFAM hypo-responsiveness of immune cells and EFAM production from cells have been found associated with disease. We hypothesize that changes in ratio of EFAMs are the normal physiological responses to stressors, but when stressors are excessive or prolonged, EFAM systems may become unpredictably hypo-responsive owing to factors such as receptor down regulation and substrate depletion. In time, many homeostatic system become deranged and held in that state by minor stressors. Literature review of chronic fatigue syndrome (CFS) shows hyper and hypo-responsiveness in immune function, several Hypothalamo-Pituitary (HP) axes and sympathetic nervous system, all relatable to dysfunctional changes in EFA metabolism. For the first time, we explain chronic immune system activation and hypo-responsive immune function in CFS; through EFAMs. Dietary EFA modulation (DEFA) can alter ratios of both membrane EFAs and produced EFAMs, and if maintained can restore hypo-responsive function. We discuss dietary strategies and relevance in CFS, and a case series of CFS patients applying DEFA with other titrated published managements which saw 90% gaining improvement within 3 months and more than 2/3 fit for full time duties. This hypothesis and DEFA may have relevance in other chronic conditions.