Tag: 1999

Human herpesviruses in chronic fatigue syndrome

Abstract:

We have conducted a double-blind study to assess the possible involvement of the human herpesviruses (HHVs) HHV6, HHV7, Epstein-Barr virus (EBV), and cytomegalovirus in chronic fatigue syndrome (CFS) patients compared to age-, race-, and gender-matched controls.

The CFS patient population was composed of rigorously screened civilian and Persian Gulf War veterans meeting the Centers for Disease Control and Prevention’s CFS case definition criteria. Healthy control civilian and veteran populations had no evidence of CFS or any other exclusionary medical or psychiatric condition. Patient peripheral blood mononuclear cells were analyzed by PCR for the presence of these HHVs.

Using two-tailed Fisher’s exact test analyses, we were unable to ascertain any statistically significant differences between the CFS patient and control populations in terms of the detection of one or more of these viruses. This observation was upheld when the CFS populations were further stratified with regard to the presence or absence of major axis I psychopathology and patient self-reported gradual versus acute onset of disease. In tandem, we performed serological analyses of serum anti-EBV and anti-HHV6 antibody titers and found no significant differences between the CFS and control patients.

 

Source: Wallace HL 2nd, Natelson B, Gause W, Hay J. Human herpesviruses in chronic fatigue syndrome. Clin Diagn Lab Immunol. 1999 Mar;6(2):216-23. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC95690/ (Full article)

 

Low-dose hydrocortisone in chronic fatigue syndrome: a randomised crossover trial

Abstract:

BACKGROUND: Reports of mild hypocortisolism in chronic fatigue syndrome led us to postulate that low-dose hydrocortisone therapy may be an effective treatment.

METHODS: In a randomised crossover trial, we screened 218 patients with chronic fatigue. 32 patients met our strict criteria for chronic fatigue syndrome without co-morbid psychiatric disorder. The eligible patients received consecutive treatment with low-dose hydrocortisone (5 mg or 10 mg daily) for 1 month and placebo for 1 month; the order of treatment was randomly assigned. Analysis was by intention to treat.

FINDINGS: None of the patients dropped out. Compared with the baseline self-reported fatigue scores (mean 25.1 points), the score fell by 7.2 points for patients on hydrocortisone and by 3.3 points for those on placebo (paired difference in mean scores 4.5 points [95% CI 1.2-7.7], p=0.009). In nine (28%) of the 32 patients on hydrocortisone, fatigue scores reached a predefined cut-off value similar to the normal population score, compared with three (9%) of the 32 on placebo (Fisher’s exact test p=0.05). The degree of disability was reduced with hydrocortisone treatment, but not with placebo. Insulin stress tests showed that endogenous adrenal function was not suppressed by hydrocortisone. Minor side-effects were reported by three patients after hydrocortisone treatment and by one patient after placebo.

INTERPRETATION: In some patients with chronic fatigue syndrome, low-dose hydrocortisone reduces fatigue levels in the short term. Treatment for a longer time and follow-up studies are needed to find out whether this effect could be clinically useful.

Comment in:

Hydrocortisone and chronic fatigue syndrome. [Lancet. 1999]

Hydrocortisone and chronic fatigue syndrome. [Lancet. 1999]

Chronic fatigue syndrome and functional hypoadrenia–fighting vainly the old ennui. [Lancet. 1999]

Hydrocortisone and chronic fatigue syndrome. [Lancet. 1999]

Hydrocortisone and chronic fatigue syndrome. [Lancet. 1999]

 

Source: Cleare AJ, Heap E, Malhi GS, Wessely S, O’Keane V, Miell J. Low-dose hydrocortisone in chronic fatigue syndrome: a randomised crossover trial. Lancet. 1999 Feb 6;353(9151):455-8. http://www.ncbi.nlm.nih.gov/pubmed/9989716

 

Increased production of interleukin-6 by adherent and non-adherent mononuclear cells during ‘natural fatigue’ but not following ‘experimental fatigue’ in patients with chronic fatigue syndrome

Abstract:

In an investigator-blinded study, adherent (monocytes) and non-adherent cells (lymphocytes) from patients with chronic fatigue syndrome (CFS) were examined on two separate occasions (when feeling ‘fatigued’ and when feeling ‘rested’) for in vitro spontaneous, phytohemagglutinin- (PHA, for lymphocytes), and lipopolysaccharide- (LPS, for monocytes) induced production of IL-6 by ELISA assay.

A group of CFS patients and controls were also subjected to exercise-induced fatigue (‘experimental fatigue’) and IL-6 production was compared, in a double-blinded manner, prior to and following induction of fatigue.

A significant increase in spontaneous, PHA- and LPS-induced IL-6 secretion by both lymphocytes and monocytes was observed in CFS patients during ‘natural fatigue’ as compared to during state. However, no such changes in IL-6 production were observed during ‘experimental fatigue’.

These data suggest a role of IL-6 in natural symptomatology and perhaps in the pathogenesis of CFS. In addition, the data demonstrate that laboratory-induced fatigue (experimental fatigue) may not be a good model to study immunological changes in CFS; immunological parameters should be studied in a longitudinal manner during the natural course of the disease.

 

Source: Gupta S, Aggarwal S, Starr A. Increased production of interleukin-6 by adherent and non-adherent mononuclear cells during ‘natural fatigue’ but not following ‘experimental fatigue’ in patients with chronic fatigue syndrome. Int J Mol Med. 1999 Feb;3(2):209-13. http://www.ncbi.nlm.nih.gov/pubmed/9917531

 

Orthostatic intolerance in adolescent chronic fatigue syndrome

Abstract:

OBJECTIVES: To demonstrate the association between orthostatic intolerance and the chronic fatigue syndrome (CFS) in adolescents and to delineate the form that orthostatic intolerance takes in these children.

STUDY DESIGN: We investigated the heart rate and blood pressure (BP) responses to head-up tilt (HUT) in 26 adolescents aged 11 to 19 years with CFS compared with responses in adolescents referred for the evaluation of simple faint and to responses in 13 normal healthy control children of similar age.

RESULTS: A total of 4/13 of the controls and 18/26 simple faint patients experienced typical faints with an abrupt decrease in BP and heart rate associated with loss of consciousness. One CFS patient had a normal HUT. A total of 25/26 CFS patients experienced severe orthostatic symptoms associated with syncope in 7/25, orthostatic tachycardia with hypotension in 15/25, and orthostatic tachycardia without significant hypotension in 3/25. Acrocyanosis, cool extremities, and edema indicated venous pooling in 18/25. None of the control or simple faint patients experienced comparable acral or tachycardic findings.

CONCLUSIONS: We conclude that chronic fatigue syndrome is highly related to orthostatic intolerance in adolescents. The orthostatic intolerance of CFS often has heart rate and BP responses similar to responses in the syndrome of orthostatic tachycardia suggesting that a partial autonomic defect may contribute to symptomatology in these patients.

 

Source: Stewart JM, Gewitz MH, Weldon A, Arlievsky N, Li K, Munoz J. Orthostatic intolerance in adolescent chronic fatigue syndrome. Pediatrics. 1999 Jan;103(1):116-21. http://www.ncbi.nlm.nih.gov/pubmed/9917448

 

Changes in immune parameters seen in Gulf War veterans but not in civilians with chronic fatigue syndrome

Abstract:

The purpose of this study was to evaluate immune function through the assessment of lymphocyte subpopulations (total T cells, major histocompatibility complex [MHC] I- and II-restricted T cells, B cells, NK cells, MHC II-restricted T-cell-derived naive and memory cells, and several MHC I-restricted T-cell activation markers) and the measurement of cytokine gene expression (interleukin 2 [IL-2], IL-4, IL-6, IL-10, IL-12, gamma interferon [IFN-gamma], and tumor necrosis factor alpha [TNF-alpha]) from peripheral blood lymphocytes.

Subjects included two groups of patients meeting published case definitions for chronic fatigue syndrome (CFS)-a group of veterans who developed their illness following their return home from participating in the Gulf War and a group of nonveterans who developed the illness sporadically. Case control comparison groups were comprised of healthy Gulf War veterans and nonveterans, respectively.

We found no significant difference for any of the immune variables in the nonveteran population. In contrast, veterans with CFS had significantly more total T cells and MHC II+ T cells and a significantly higher percentage of these lymphocyte subpopulations, as well as a significantly lower percentage of NK cells, than the respective controls.

In addition, veterans with CFS had significantly higher levels of IL-2, IL-10, IFN-gamma, and TNF-alpha than the controls. These data do not support the hypothesis of immune dysfunction in the genesis of CFS for sporadic cases of CFS but do suggest that service in the Persian Gulf is associated with an altered immune status in veterans who returned with severe fatiguing illness.

 

Source: Zhang Q, Zhou XD, Denny T, Ottenweller JE, Lange G, LaManca JJ, Lavietes MH, Pollet C, Gause WC, Natelson BH. Changes in immune parameters seen in Gulf War veterans but not in civilians with chronic fatigue syndrome. Clin Diagn Lab Immunol. 1999 Jan;6(1):6-13. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC95652/ (Full article)

 

Chronic fatigue syndrome: a hypothesis focusing on the autonomic nervous system

Abstract:

Chronic fatigue syndrome is a debilitating illness of unknown aetiology, with estimated levels of prevalence of up to about 8. 7/100 000 in the U.S.A. Like pain fatigue it is a personal, emotionally rich experience, which may originate from peripheral or central sites (or both). The nature of the symptoms is complex and reflects the interaction of the patient with the environment and cultural milieu. Accordingly the common use of the same terminology for different types of fatigue may be misleading.

Autonomic activation is a key component of both real and simulated physical exercise. Alterations in autonomic nervous system activity are a key component of several physiopathological conditions. In chronic fatigue syndrome disturbances in autonomic activity, and in other homoeostatic mechanisms, such as the hormonal and immune systems, have been reported recently.

In this review we followed the hypothesis that in chronic fatigue syndrome the paradoxical condition of disturbing somatic symptoms in the absence of organic evidence of disease might be addressed by focusing on attending functional correlates. In particular we addressed possible alterations in cardiovascular autonomic control, as can be assessed by spectral analysis of R-R interval and systolic arterial pressure variability.

With this approach, in subjects complaining of unexplained fatigue, we obtained data suggesting a condition of prevailing sympathetic modulation of the sino-atrial node at rest, and reduced responsiveness to excitatory stimuli. Far from considering the issue resolved, we propose that in the context of the multiple physiological and psychological interactions involved in the perception and self-reporting of symptoms, attendant changes in physiological equivalents might furnish a convenient assessment independent from subjective components.

Indices of sympathetic modulation could, accordingly, provide quantifiable signs of the interaction between subject’s efforts and environmental demands, independently of self descriptions, which could provide convenient measurable outcomes, both for diagnosis and treatment titration in chronic fatigue syndrome.

Comment in: Long- and short-term blood pressure and RR-interval variability and psychosomatic distress in chronic fatigue syndrome. [Clin Sci (Lond). 1999]

 

Source: Pagani M, Lucini D. Chronic fatigue syndrome: a hypothesis focusing on the autonomic nervous system. Clin Sci (Lond). 1999 Jan;96(1):117-25. http://www.ncbi.nlm.nih.gov/pubmed/9857114