The role of environmental factors in medically unexplained symptoms and related syndromes: conference summary and recommendations

Abstract:

This monograph of peer-reviewed articles is based on presentations at the conference “Environmental Factors in Medically Unexplained Physical Symptoms and Related Syndromes” held 10-12 January 2001 in Piscataway, New Jersey, USA. The purpose of the conference was to determine research priorities for elucidating the role of environmental factors in medically unexplained symptoms and symptom syndromes. These include conditions such as chronic fatigue syndrome, multiple chemical sensitivities, sick building syndrome, Gulf War illness, and the like. Approximately 1 1/2 days were devoted to plenary talks and 1 day was devoted to break-out sessions to discuss epidemiologic, psychosocial, and experimental research. Recommendations were made for a series of epidemiologic, psychosocial, and experimental research approaches, with acknowledgment that nosology issues are clearly fundamental to advancing understanding of these conditions.

 

Source: Kipen HM, Fiedler N. The role of environmental factors in medically unexplained symptoms and related syndromes: conference summary and recommendations. Environ Health Perspect. 2002 Aug;110 Suppl 4:591-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1241210/ (Full article)

 

Chronic unexplained fatigue

After more than two years’ gestation, an independent working group, set up by the previous Chief Medical Officer for England, published its final report on the subject of chronic fatigue syndrome (CFS) in January of this year.1 This is a topical subject in the English speaking world as two other management reports have been published in the last six months, by the US government and the Australasian Royal College of Physicians.2 3 The Canadians are also close to a final draft of their own report. This has occurred at the same time as the release of two independent systematic reviews of management. Remarkably the two teams from Texas (USA) and York (UK) reached such similar conclusions that they combined their findings into the one paper.4 The York group has just published their own guidance based on their systematic review.5

You can read the rest of this editorial here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1742445/pdf/v078p00445.pdf

CONFLICT OF INTEREST Dr White was one of the clinicians who resigned from the English report on CFS/ME.

Comment in: Chronic unexplained fatigue. [Postgrad Med J. 2002]

 

Source: White PD. Chronic unexplained fatigue. Postgrad Med J. 2002 Aug;78(922):445-6. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1742445/pdf/v078p00445.pdf (Full article)

 

IgM serum antibodies to human cytomegalovirus nonstructural gene products p52 and CM2(UL44 and UL57) are uniquely present in a subset of patients with chronic fatigue syndrome

Abstract:

Human cytomegalovirus (HCMV) IgM serum antibodies to two nonstructural gene products UL44 and UL57 (p52 and CM2) were assayed in patients with the diagnosis of the chronic fatigue syndrome (CFS) according to criteria established by the US Centers for Disease Control and Prevention. A subset of 16 CFS patients demonstrated HCMV IgG, but no HCMV IgM serum antibodies to conformational structural HCMV antigens (designated, V). By convention, these findings are interpreted to indicate only a remote HCMV infection.

However, HCMV IgM p52 and CM2 antibodies were uniquely present in these 16 CFS patients. Other CFS patients with similar HCMV (V) IgG antibodies (18 patients), non-fatigued HCMV (V) IgG-positive control patients (18 patients), random HCMV (V) IgG-positive control patients from a clinical laboratory (26 patients), and non-fatigued HCMV (V) IgG-negative control patients (15 patients) did not have HCMV, IgM p52 or CM2 serum antibodies (p < 0.05). Control HCMV (V) IgG-positive patients had no serum IgM HCMV (V) antibodies to conventional structural HCMV (V) antigen. Thus, 77 various control patients did not contain IgM p52 or CM2 serum antibodies. The presence of IgM p52 and/or CM2 HCMV serum antibodies in this subset of CSF-specific patients may detect incomplete HCMV multiplication in which a part of the HCMV protein-coding content of the HCMV genome is processed, but remains unassembled.

These findings suggest that the presence of HCMV IgM p52 and CM2 serum antibodies may be a specific diagnostic test for the diagnosis of a subset of CFS patients. Further, these data suggest an etiologic relationship for HCMV infection in this group of CFS patients

 

Source: Lerner AM, Beqaj SH, Deeter RG, Fitzgerald JT. IgM serum antibodies to human cytomegalovirus nonstructural gene products p52 and CM2(UL44 and UL57) are uniquely present in a subset of patients with chronic fatigue syndrome. In Vivo. 2002 May-Jun;16(3):153-9. http://www.ncbi.nlm.nih.gov/pubmed/12182109

 

A computational analysis of Canale-Smith syndrome: chronic lymphadenopathy simulating malignant lymphoma

Abstract:

OBJECTIVE: The objective of this study was to simulate changes in the human T cell system representing Canale-Smith syndrome using a dynamic computer model of T cell development and comparing with available human data.

STUDY DESIGN: Physiological stepwise maturation and function of T lymphocytes in the computer model is altered by introducing functional disturbances following lymphotropic virus infection. In the present model, acute and chronic persistent infection with the human herpesvirus-6 (HHV-6) was simulated, and ensuing changes in T cell populations were compared with those measured in human patients.

RESULTS: Using our computer model we previously found that simulated acute HHV-6 infection produced T cell computer data, which resembled an infectious mononucleosis-like disease in patients. Simulated chronic persistent infection, instead, resulted in variable cell changes comparing well to patients with chronic fatigue syndrome. In one setting, however, persistent immature lymphocytosis was observed similar to what initial has been described in this journal as Canale-Smith syndrome.

CONCLUSION: Using a computer model developed by us we were able to produce simulations that resemble the immune system features of Canale-Smith syndrome. Further understanding of these simulation results may possibly guide future investigations into this disorder.

 

Source: Krueger GR, Brandt ME, Wang G, Berthold F, Buja LM. A computational analysis of Canale-Smith syndrome: chronic lymphadenopathy simulating malignant lymphoma. Anticancer Res. 2002 Jul-Aug;22(4):2365-71. http://www.ncbi.nlm.nih.gov/pubmed/12174928

 

Markers of viral infection in monozygotic twins discordant for chronic fatigue syndrome

Abstract:

To estimate the prevalence of viruses associated with chronic fatigue syndrome (CFS) and to control for genetic and environmental factors, we conducted a co-twin control study of 22 monozygotic twin pairs, of which one twin met criteria for CFS and the other twin was healthy. Levels of antibodies to human herpesvirus (HHV)-8, cytomegalovirus, herpes simplex virus 1 and 2, and hepatitis C virus were measured. Polymerase chain reaction (PCR) assays for viral DNA were performed on peripheral blood mononuclear cell specimens to detect infection with HHV-6, HHV-7, HHV-8, cytomegalovirus, Epstein-Barr virus, herpes simplex virus, varicella zoster virus, JC virus, BK virus, and parvovirus B19. To detect lytic infection, plasma was tested by PCR for HHV-6, HHV-8, cytomegalovirus, and Epstein-Barr virus DNA, and saliva was examined for HHV-8 DNA. For all assays, results did not differ between the group of twins with CFS and the healthy twins.

Comment in: Diverse etiologies for chronic fatigue syndrome. [Clin Infect Dis. 2003]

 

Source: Koelle DM, Barcy S, Huang ML, Ashley RL, Corey L, Zeh J, Ashton S, Buchwald D. Markers of viral infection in monozygotic twins discordant for chronic fatigue syndrome. Clin Infect Dis. 2002 Sep 1;35(5):518-25. Epub 2002 Jul 31. http://cid.oxfordjournals.org/content/35/5/518.long (Full article)

 

Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia

Abstract:

BACKGROUND: Chronic fatigue syndrome and fibromyalgia continue to be perplexing conditions of unknown validity. Aetiological and symptomatic heterogeneity is likely and the distinctiveness of these disorders remains unclear. Our aims were to investigate empirically symptomatic heterogeneity in chronic fatigue syndrome and fibromyalgia.

METHODS: Latent class analysis was applied to data from 646 patients who met accepted criteria for chronic fatigue syndrome and/or fibromyalgia who were systematically evaluated at a specialist fatigue clinic. Thirty-two symptoms commonly found in chronic fatigue syndrome and fibromyalgia were entered into the latent class analysis.

RESULTS: We chose to interpret a four class solution. The classes appeared to differ in a graded fashion (rather than qualitatively) for symptom endorsements, pre-morbid characteristics, and co-morbidity with panic disorder and major depression.

CONCLUSIONS: These results were unexpected given the usual assumption of the distinctiveness of chronic fatigue syndrome and fibromyalgia. These results support a conceptualization of chronic fatigue syndrome and fibromyalgia as being characterized by greater similarities than differences.

 

Source: Sullivan PF, Smith W, Buchwald D. Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia. Psychol Med. 2002 Jul;32(5):881-8. http://www.ncbi.nlm.nih.gov/pubmed/12171382

 

Long-term follow-up of patients from the 1989 Q fever outbreak: no evidence of excess cardiac disease in those with fatigue

Abstract:

BACKGROUND: In 1989, an outbreak of Q fever (C. burnetii infection) with 147 confirmed cases occurred in Solihull, West Midlands. Three patients developed cardiomyopathy in the subsequent 10 years. The cohort has been followed up with respect to the development of fatigue and, in this instance, cardiac effects after the original infection.

AIM: To determine whether persisting fatigue after Q fever represented sub-clinical cardiomyopathy.

DESIGN: Prospective follow-up study.

METHODS: All traceable subjects from the original outbreak, and community age-, sex- and smoking-matched controls, were studied. Questionnaires for idiopathic fatigue, 12-lead ECG, echocardiography, spirometry and shuttle walk distance were undertaken, and a subset with CDC-defined chronic fatigue syndrome had gated cardiac scans.

RESULTS: Of the original cohort, 19 had died, three had emigrated and 10 were untraceable. Of the remaining 115, 108 responded to a mailed questionnaire and 87 were investigated further, of whom 85 provided complete data. Two developed aortic valve vegetations, one of whom died. Chronic fatigue syndrome was found in 20% of cases and 5.3% of controls (including those with co-morbidities), falling to 8.2% and 0 when excluding those with co-morbidities. There were no significant differences in ECG and echocardiographic investigations or shuttle-walk distance between those with fatigue and those without. Six of the seven patients with CFS had gated cardiac scans: all were within normal limits.

CONCLUSIONS: These findings do not support the existence of a sub-clinical cardiomyopathy in the patients in this cohort who suffer from fatigue after acute Q fever, although endocarditis can occur after acute infection.

Comment in: Q fever: still a mysterious disease. [QJM. 2002]

 

Source: Ayres JG, Wildman M, Groves J, Ment J, Smith EG, Beattie JM. Long-term follow-up of patients from the 1989 Q fever outbreak: no evidence of excess cardiac disease in those with fatigue. QJM. 2002 Aug;95(8):539-46. http://qjmed.oxfordjournals.org/content/95/8/539.long (Full article)

 

Chronic fatigue following infection by Coxiella burnetii (Q fever): ten-year follow-up of the 1989 UK outbreak cohort

Abstract:

BACKGROUND: Some patients exposed to Q fever (Coxiella burnetii infection) may develop chronic fatigue.

AIM: To determine whether subjects involved in the West Midlands Q fever outbreak of 1989 had increased fatigue, compared to non-exposed controls, 10 years after exposure.

DESIGN: Matched cohort study comparing cases to age-, sex- and smoking-history-matched controls not exposed to Q fever.

METHODS: A postal questionnaire was sent to subjects at home, followed by further assessment in hospital, including a physical examination and blood tests.

RESULTS: Of 108 Q-exposed subjects, 70 (64.8%) had fatigue, 37 idiopathic chronic fatigue (ICF) (34.3%), vs. 29/80 (36.3%) and 12 (15.0%), respectively, in controls. In 77 matched pairs, fatigue was commoner in Q-exposed subjects than in controls: 50 (64.9%) vs. 27 (35.1%), p<0.0001. ICF was found in 25 (32.5%) of Q-exposed patients and 11(14.3%) of controls (p=0.01). There were 36 (46.8%) GHQ cases in Q-exposed subjects, vs. 18 (23.4%) controls (p=0.004). A matched analysis of those more intensively studied showed fatigue in 48 (66.7%) Q-exposed patients and 25 (34.7%) controls, (p<0.0001), ICF in 25 (34.7%) Q-exposed and 10 (13.9%) controls (p=0.004), and chronic fatigue syndrome (CFS) in 14 (19.4%) Q-exposed patients and three (4.2%) controls (p=0.003). Thirty-four (47.2%) Q-exposed patients were GHQ cases compared to 17 (23.6%) controls (p=0.004).

DISCUSSION: Subjects who were exposed to Coxiella in 1989 had more fatigue than did controls, and some fulfilled the criteria for CFS. Whether this is due to ongoing antigen persistence or to the psychological effects of prolonged medical follow-up is uncertain.

Comment in: Q fever: still a mysterious disease. [QJM. 2002]

 

Source: Wildman MJ, Smith EG, Groves J, Beattie JM, Caul EO, Ayres JG. Chronic fatigue following infection by Coxiella burnetii (Q fever): ten-year follow-up of the 1989 UK outbreak cohort. QJM. 2002 Aug;95(8):527-38. http://qjmed.oxfordjournals.org/content/95/8/527.long (Full article)

 

Peripheral blood mononuclear cell beta-endorphin concentration is decreased in chronic fatigue syndrome and fibromyalgia but not in depression: preliminary report

Abstract:

OBJECTIVE: The aim of this study was to examine the possible role of the immune system in the pathophysiology of chronic fatigue syndrome and fibromyalgia syndrome and in the differential diagnosis of depression by investigating changes in peripheral blood mononuclear cell levels of beta-endorphin, an endogenous opioid known to be involved in regulation of the immune system function.

DESIGN: Beta-endorphin concentrations were measured by radioimmunoassay in peripheral blood mononuclear cells from healthy controls (n = 8) and patients with chronic fatigue syndrome (n = 17), fibromyalgia syndrome (n = 5), or depression (n = 10).

RESULTS: Beta-endorphin concentrations were significantly lower in patients with chronic fatigue syndrome or fibromyalgia syndrome than in normal subjects and depressed patients (p <0.001 and p <0.01, respectively). They were significantly higher in depressed patients than in controls (p <0.01).

CONCLUSIONS: Evaluation of peripheral blood mononuclear cell beta-endorphin concentrations could represent a diagnostic tool for chronic fatigue syndrome and fibromyalgia and help with differential diagnosis of these syndromes versus depression. The results obtained are also consistent with the hypothesis that the immune system is activated in both chronic fatigue syndrome and fibromyalgia syndrome.

 

Source: Panerai AE, Vecchiet J, Panzeri P, Meroni P, Scarone S, Pizzigallo E, Giamberardino MA, Sacerdote P. Peripheral blood mononuclear cell beta-endorphin concentration is decreased in chronic fatigue syndrome and fibromyalgia but not in depression: preliminary report. Clin J Pain. 2002 Jul-Aug;18(4):270-3. http://www.ncbi.nlm.nih.gov/pubmed/12131069

 

Cytokines in nasal lavage fluids from acute sinusitis, allergic rhinitis, and chronic fatigue syndrome subjects

Abstract:

The aim of this study was to compare the degree of inflammation present in acute sinusitis, allergic rhinitis, chronic Fatigue Syndrome (CFS), and non-CFS control subjects by measuring cytokine concentrations in nasal lavage fluids. The concentrations of total protein (TP; Lowry assay), nerve growth factor (NGF), tumor necrosis factor (TNF) alpha, and interleukin (IL)-8 were measured by ELISA in nasal lavage fluids from acute sinusitis (n = 13), active allergic rhinitis (n = 16), CFS (n = 95), and non-CFS (n = 89) subjects. CFS and non-CFS groups were subdivided further using allergy skin test and rhinitis score results. Acute sinusitis subjects had significantly higher TP (p = 0.011, ANOVA), TNF-alpha (p = 0.00071), and IL-8 (p = 0.0000027) concentrations and IL-8/TP ratios (p = 0.0030) than the other three patient groups. There were no differences based on skin test or rhinitis score severity within either the CFS or non-CFS groups. The mucopurulent discharge of acute sinusitis contained significantly higher TNF-alpha and IL-8. Neutrophils were a likely source for these cytokines. There were no differences between CFS and non-CFS subjects, making it unlikely that the rhinitis of CFS has an inflammatory component.

 

Source: Repka-Ramirez S, Naranch K, Park YJ, Clauw D, Baraniuk JN. Cytokines in nasal lavage fluids from acute sinusitis, allergic rhinitis, and chronic fatigue syndrome subjects. Allergy Asthma Proc. 2002 May-Jun;23(3):185-90. http://www.ncbi.nlm.nih.gov/pubmed/12125506