Category: Viruses

Microbial infections in eight genomic subtypes of chronic fatigue syndrome/myalgic encephalomyelitis

Abstract:

BACKGROUND: The authors have previously reported genomic subtypes of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) based on expression of 88 human genes.

AIM: To attempt to reproduce these findings, determine the specificity of this signature to CFS/ME, and test for associations between CFS/ME subtype and infection.

METHODS: Expression levels of 88 human genes were determined in blood of 62 new patients with idiopathic CFS/ME (according to Fukuda criteria), six patients with Q-fever-associated CFS/ME from the Birmingham Q-fever outbreak (according to Fukuda criteria), 14 patients with endogenous depression (according to DSM-IV criteria) and 29 normal blood donors.

RESULTS: In patients with CFS/ME, differential expression was confirmed for all 88 genes. Q-CFS/ME had similar patterns of gene expression to idiopathic CFS/ME. Gene expression in patients with endogenous depression was similar to that in the normal controls, except for upregulation of five genes (APP, CREBBP, GNAS, PDCD2 and PDCD6). Clustering of combined gene data in CFS/ME patients for this and the authors’ previous study (117 CFS/ME patients) revealed genomic subtypes with distinct differences in SF36 scores, clinical phenotypes, severity and geographical distribution. Antibody testing for Epstein-Barr virus, enterovirus, Coxiella burnetii and parvovirus B19 revealed evidence of subtype-specific relationships for Epstein-Barr virus and enterovirus, the two most common infectious triggers of CFS/ME.

CONCLUSIONS: This study confirms the involvement of these genes in CFS/ME.

 

Source: Zhang L, Gough J, Christmas D, Mattey DL, Richards SC, Main J, Enlander D, Honeybourne D, Ayres JG, Nutt DJ, Kerr JR. Microbial infections in eight genomic subtypes of chronic fatigue syndrome/myalgic encephalomyelitis. J Clin Pathol. 2010 Feb;63(2):156-64. doi: 10.1136/jcp.2009.072561. Epub 2009 Dec 2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2921262/ (Full article)

 

Acute enterovirus infection followed by myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS) and viral persistence

Abstract:

AIMS: Enteroviruses are well-known causes of acute respiratory and/or gastrointestinal infections and non-specific flu-like illness. Although enterovirus protein, RNA and non-cytopathic viruses have been demonstrated in the stomach biopsies of patients with myalgia encephalomyelitis/chronic fatigue syndrome (ME/CFS), causality for chronic diseases is difficult to establish without having well-documented cases of acute enterovirus infections. The aim of this study was to link acute enteroviral infection to viral persistence in patients with ME/CFS.

METHOD: Patients admitted to the hospital with acute febrile illnesses were screened for enteroviral infections. Acutely infected patients were followed longitudinally, and those who developed symptoms of ME/CFS underwent oesophagogastroduodenoscopy and biopsies of the antrum to document viral persistence by immunoperoxidase staining for viral protein and viral RNA assay.

RESULTS: Three representative patients with different manifestations of acute enterovirus infections progressed to have chronic symptoms of ME/CFS. Persistent viral infection was demonstrated in the antrum years later.

CONCLUSION: After acute infections, enteroviruses can persist in patients resulting in manifestation of ME/CFS. Chronic enterovirus infection in an immunocompetent host may be an example of a stalemate between attenuated, intracellular viruses and an ineffective immune response.

 

Source: Chia J, Chia A, Voeller M, Lee T, Chang R. Acute enterovirus infection followed by myalgic encephalomyelitis/chronic fatigue syndrome(ME/CFS) and viral persistence. J Clin Pathol. 2010 Feb;63(2):165-8. doi: 10.1136/jcp.2009.070466. Epub 2009 Oct 14. https://www.ncbi.nlm.nih.gov/pubmed/19828908

 

Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease of unknown etiology that is estimated to affect 17 million people worldwide. Studying peripheral blood mononuclear cells (PBMCs) from CFS patients, we identified DNA from a human gammaretrovirus, xenotropic murine leukemia virus-related virus (XMRV), in 68 of 101 patients (67%) as compared to 8 of 218 (3.7%) healthy controls. Cell culture experiments revealed that patient-derived XMRV is infectious and that both cell-associated and cell-free transmission of the virus are possible. Secondary viral infections were established in uninfected primary lymphocytes and indicator cell lines after their exposure to activated PBMCs, B cells, T cells, or plasma derived from CFS patients. These findings raise the possibility that XMRV may be a contributing factor in the pathogenesis of CFS.

Comment in:

Erratum in: Partial retraction. Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. [Science. 2011]

Retraction in: Retraction. [Science. 2011]

 

Source: Lombardi VC, Ruscetti FW, Das Gupta J, Pfost MA, Hagen KS, Peterson DL, Ruscetti SK, Bagni RK, Petrow-Sadowski C, Gold B, Dean M, Silverman RH, Mikovits JA. Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. Science. 2009 Oct 23;326(5952):585-9. doi: 10.1126/science.1179052. Epub 2009 Oct 8. http://science.sciencemag.org/content/326/5952/585.long (Full article)

 

Virology. A new virus for old diseases?

There is little consensus in the medical community on whether chronic fatigue syndrome is a distinct disease. As its name implies, the condition is characterized by debilitating fatigue persisting for many years, and it affects as much as 1% of the world’s population. Although chronic inflammation is often found in these patients, no infectious or toxic agent has been clearly implicated in this disease, which is diagnosed largely by excluding other conditions that cause similar symptoms (1). In this week’s Science Express, Lombardi et al. (2) describe the detection of xenotropic murine leukemia virus–related virus (XMRV) in about two-thirds of patients diagnosed with chronic fatigue syndrome. Both laboratory and epidemiological studies are now needed to determine whether this virus has a causative role, not only in this disease, but perhaps in others as well.

Chronic fatigue syndrome is not the first human disease to which XMRV has been linked. The virus first was described about 3 years ago in a few prostate cancer patients (3), and recently detected in nearly a quarter of all prostate cancer biopsies (4). It has been isolated from both prostate cancer and chronic fatigue syndrome patients, and is similar to a group of endogenous murine leukemia viruses (MLVs) found in the genomes of inbred and related wild mice. Although a half century of studies on MLVs and other gammaretroviruses have led to important discoveries on which much of our current understanding of cancer rests, there has been no clear evidence demonstrating human infection with gammaretroviruses, or associating these agents with any human disease.

You can read the rest of this article here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818280/

Comment on: Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. [Science. 2009]

 

Source: Coffin JM, Stoye JP. Virology. A new virus for old diseases? Science. 2009 Oct 23;326(5952):530-1. doi: 10.1126/science.1181349. Epub 2009 Oct 8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818280/ (Full article)

 

Sensitive, qualitative detection of human herpesvirus-6 and simultaneous differentiation of variants A and B

Abstract:

BACKGROUND: The current limitations of laboratory testing for the detection of human herpesvirus virus 6 (HHV-6) in clinical specimens with low HHV-6 viral loads make this area a priority for further research and development.

OBJECTIVES: To develop and validate a sensitive qualitative assay for simultaneous HHV-6 detection and variant differentiation.

METHODS: We developed a diagnostic procedure, which combines a magnetic bead-based nucleic acid extraction, PCR amplification, and colorimetric microtiter plate identification (MAG-PCR-EIA), for the sensitive detection of HHV-6 and the simultaneous differentiation of HHV-6A and HHV-6B.

RESULTS: Analytic sensitivities of the MAG-PCR-EIA assay were 10 copies per reaction for both HHV-6A and HHV-6B variants, which is equivalent to 20 copies/ml when 1ml of clinical specimen was processed. A proficiency panel containing 11 blinded specimens covering HHV-6A viral loads from 0 to 100,000 copies was tested, and the MAG-PCR-EIA was able to detect the lowest concentration at one copy in 200microl. A panel of 27 urine specimens, which were collected from patients with and without chronic fatigue syndrome, was tested by the MAG-PCR-EIA. HHV-6 was detected in two (HHV-6A) patients who have chromosomally integrated HHV-6A and in one (HHV-6B) patient who was a healthy control and diagnosed as cervical cancer later on. The HHV-6 results did not correlate with results previously determined by HHV-6 antigenemia in urine.

CONCLUSION: With large specimen volumes processed and an additional signal amplification incorporated, the MAG-PCR-EIA provides a sensitive and qualitative system for HHV-6 detection and simultaneous variant differentiation. Clinical relevance of the assay awaits further investigation.

 

Source: Li H, Meng S, Levine SM, Stratton CW, Tang YW. Sensitive, qualitative detection of human herpesvirus-6 and simultaneous differentiation of variants A and B. J Clin Virol. 2009 Sep;46(1):20-3. doi: 10.1016/j.jcv.2009.05.016. Epub 2009 Jun 21. https://www.ncbi.nlm.nih.gov/pubmed/19540801

 

Does varicella-zoster virus infection of the peripheral ganglia cause Chronic Fatigue Syndrome?

Abstract:

This article posits that infection of the peripheral ganglia causes at least some cases of Chronic Fatigue Syndrome (CFS), with a neurotropic herpesvirus, particularly varicella-zoster virus (VZV), as the most likely cause of the infection. Virtually all CFS symptoms could be produced by an infection of the peripheral ganglia, with infection of the autonomic ganglia causing fatigue, postural hypotension, and sleep disturbances, and infection of the sensory ganglia causing sensory symptoms such as chronic pain. Furthermore, infections of the peripheral ganglia are known to cause long-term nerve dysfunction, which would help explain the chronic course of CFS.

Herpesviruses have long been suspected as the cause of CFS; this theory has recently been supported by studies showing that administering antiherpes agents causes substantial improvement in some CFS patients. VZV is known to frequently reactivate in the peripheral ganglia of previously healthy adults and cause sudden, debilitating illness, making it a likely candidate as a cause of CFS. Moreover, many of the symptoms of CFS overlap with those of herpes zoster (shingles), with the exception that painful rash is not one of the symptoms of CFS.

A model is therefore proposed in which CFS is one of the many manifestations of zoster sine herpete; that is, herpes zoster without rash. Furthermore, re-exposure to VZV in the form of chickenpox has become less common in the past few decades; without such re-exposure, immunity to VZV drops, which could explain the increased incidence of CFS. Co-infection with multiple herpesviruses is a possibility, as some CFS patients show signs of infection with other herpesviruses including Epstein-Barr, Cytomegalovirus, and HHV6. These three herpesviruses can attack immune cells, and may therefore promote neurotropic herpesvirus reactivation in the ganglia.

The possibility of VZV as the causal agent in CFS has previously received almost no attention; the possibility that CFS involves infection of the peripheral ganglia has likewise been largely overlooked. This suggests that the search for a viral cause of CFS has been far from exhaustive. Several antiherpes drugs are available, as is a vaccine for VZV; more research into such agents as possible treatments for CFS is urgently needed.

 

Source: Shapiro JS. Does varicella-zoster virus infection of the peripheral ganglia cause Chronic Fatigue Syndrome? Med Hypotheses. 2009 Nov;73(5):728-34. doi: 10.1016/j.mehy.2009.04.043. Epub 2009 Jun 10. https://www.ncbi.nlm.nih.gov/pubmed/19520522

 

Detection of herpesviruses and parvovirus B19 in gastric and intestinal mucosa of chronic fatigue syndrome patients

Abstract:

BACKGROUND: Human herpesvirus-6 (HHV-6), Epstein-Barr virus and parvovirus B19 have been suggested as etiological agents of chronic fatigue syndrome but none of these viruses is consistently detected in all patients. However, active viral infections may be localized in specific tissues, and, therefore, are not easily detectable. The aim of this study was to investigate the presence of HHV-6, HHV-7, EBV and parvovirus B19 in the gastro-intestinal tract of CFS patients.

PATIENTS AND METHODS: Using real-time PCR, viral DNA loads were quantified in gastro-intestinal biopsies of 48 CFS patients and 35 controls.

RESULTS: High loads of HHV-7 DNA were detected in most CFS and control biopsies. EBV and HHV-6 were detected in 15-30% of all biopsies. Parvovirus B19 DNA was detected in 40% of the patients versus less than 15% of the controls.

CONCLUSION: Parvovirus B19 may be involved in the pathogenesis of CFS, at least for a subset of patients. The gastro-intestinal tract appears as an important reservoir of infection for several potentially pathogenic viruses.

 

Source: Frémont M, Metzger K, Rady H, Hulstaert J, De Meirleir K. Detection of herpesviruses and parvovirus B19 in gastric and intestinal mucosa of chronic fatigue syndrome patients. In Vivo. 2009 Mar-Apr;23(2):209-13. http://iv.iiarjournals.org/content/23/2/209.long (Full article)

 

Chronic fatigue syndrome and complement activation

Abstract:

This report describes a case of chronic fatigue syndrome (CFS) that followed a well-documented episode of acute Epstein-Barr virus (EBV) mononucleosis. All aetiological tests for chronic fatigue were found to be negative or normal, as were immunological tests. After 2 years of chronic fatigue following the acute illness, measurements of complement split products were performed to test for complement activation. These were positive and remained positive for 14 months, after which the patient then recovered from CFS.

 

Source: Geller RD, Giclas PC. Chronic fatigue syndrome and complement activation. BMJ Case Rep. 2009;2009. pii: bcr08.2008.0819. doi: 10.1136/bcr.08.2008.0819. Epub 2009 Mar 17. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3028106/ (Full article)

 

Is chronic fatigue syndrome caused by a rare brain infection of a common, normally benign virus?

Abstract:

Chronic fatigue syndrome (CFS) is a disabling disease of unknown aetiology. A variety of factors have been suggested as possible causes. Although the symptoms and clinical findings are heterogeneous, the syndrome is sufficiently distinct, at least in relation to the more obvious cases, that a common explanation seems likely. In this paper, it is proposed that the disease is caused by a ubiquitous, but normally benign virus, e.g., one of the circoviruses.

Circoviruses are chronically present in a majority of people, but are rarely tested for diagnostically. Normally these viruses do not penetrate the blood-brain barrier, but exceptions have been reported, and related viruses cause disease in the central nervous system of animals.

The flu-like illness that often precedes the onset of CFS may either suppress immune function, causing an increased viremia, and/or lower the blood-brain barrier. In both cases the result may be that a virus already present in the blood enters the brain. It is well known that zoonotic viruses typically are more malignant than viruses with a long history of host-virus evolution. Similarly, a virus reaching an unfamiliar organ may cause particular problems.

 

Source: Grinde B. Is chronic fatigue syndrome caused by a rare brain infection of a common, normally benign virus? Med Hypotheses. 2008 Aug;71(2):270-4. doi: 10.1016/j.mehy.2008.03.014. Epub 2008 Apr 25. https://www.ncbi.nlm.nih.gov/pubmed/18440157

 

Chronic fatigue syndrome after human parvovirus B19 infection without persistent viremia

Abstract:

BACKGROUND: It is unclear how often chronic fatigue syndrome (CFS) appears after human parvovirus B19 (B19) infection and whether prolonged B19 viremia or some other factors cause CFS.

OBJECTIVES: To determine how often CFS appears after B19 infection and whether prolonged B19 DNA presence, antibody production and persistently reduced complement levels occur in CFS patients after B19 infection.

METHODS: Clinical findings were examined in 210 patients after B19 infection, and CH50, C3 and C4 levels were determined. B19 DNA and antibodies to B19 were also tested in 38 patients’ sera including 3 with CFS.

RESULTS: Serum B19 DNA disappeared after 4-5 months in all 18 patients tested. There are no differences in B19 DNA-positive period between patients with and without persistent symptoms. IgM antibody titers to B19 became reduced after 2 months in all 38 patients. Complement levels persistently decreased in a greater proportion of patients with persistent symptoms.

CONCLUSIONS: The present study suggests that we should consider the possibility of CFS after B19 infection and that CFS may be derived from several aspects other than prolonged B19 DNA presence in sera.

Copyright 2008 S. Karger AG, Basel.

 

Source: Seishima M, Mizutani Y, Shibuya Y, Arakawa C. Chronic fatigue syndrome after human parvovirus B19 infection without persistent viremia. Dermatology. 2008;216(4):341-6. doi: 10.1159/000116723. Epub 2008 Feb 15. https://www.ncbi.nlm.nih.gov/pubmed/18277075