Evidence browser

E3 PreliminaryMechanismPEM unclearCross-Sectional

Long-term infection and vertical transmission of a gammaretrovirus in a foreign host species.

Sakuma, Toshie, Tonne, Jason M, Malcolm, Jessica A et al.·PloS one·2012

Researchers studied a virus called XMRV that can jump between animal species to understand how viruses adapt when they infect new hosts. They infected a type of mouse with XMRV and watched what happened over a year, including whether the virus could be passed to offspring. The mice stayed healthy and the virus didn't spread much to the next generation, suggesting that while the virus can infect new species, it doesn't easily take hold or spread.

No biological evidence of XMRV in blood or prostatic fluid from prostate cancer patients.

Mendoza, Ramon, Silverman, Robert H, Klein, Eric A et al.·PloS one·2012

Researchers tested blood and fluid samples from prostate cancer patients to see if they contained XMRV, a virus that was once thought to cause chronic fatigue syndrome. They found no evidence of the virus in any of the samples, including in nine patients who had previously tested positive for XMRV. This study supports the growing scientific consensus that XMRV does not actually infect humans.

Identification of XMRV infection-associated microRNAs in four cell types in culture.

Mohan, Ketha V K, Devadas, Krishnakumar, Sainath Rao, Shilpakala et al.·PloS one·2012

This study looked at how a virus called XMRV affects the behavior of microRNAs—tiny molecules that control how genes are expressed—in different types of human cells grown in the laboratory. Researchers infected four different cell types with XMRV and measured changes in microRNA patterns at different time points. They found that certain microRNAs changed in response to the virus infection.

E3 PreliminaryMechanismPEM unclearCase-Control

Cytotoxic lymphocyte microRNAs as prospective biomarkers for Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Brenu, Ekua W, Ashton, Kevin J, van Driel, Mieke et al.·Journal of affective disorders·2012

Researchers studied tiny molecules called microRNAs in immune cells from people with ME/CFS and healthy controls. They found that people with ME/CFS have lower levels of certain microRNAs in their immune cells, which may explain why their immune systems don't work as well. These microRNA changes could be useful biomarkers—like a fingerprint—to help diagnose or understand ME/CFS.

Pain and SensitizationSleep

The role of antipsychotics in the management of fibromyalgia.

Calandre, Elena P, Rico-Villademoros, Fernando·CNS drugs·2012

This review examines whether antipsychotic medications—drugs typically used to treat psychiatric conditions—might also help people with fibromyalgia manage pain, sleep problems, fatigue, and mood disturbances. The authors found that some antipsychotics, particularly quetiapine, have shown promise in small studies and case reports, though most research is preliminary and more rigorous testing is needed.

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

Multiple sources of contamination in samples from patients reported to have XMRV infection.

Kearney, Mary F, Spindler, Jonathan, Wiegand, Ann et al.·PloS one·2012

Researchers tested blood samples from ME/CFS patients that were previously reported to contain a virus called XMRV. Using careful testing methods, they found that the virus-like sequences in patient blood samples were actually contamination from mouse DNA used in lab experiments, not the XMRV virus itself. When they did find actual XMRV virus, it appeared in healthy control samples and came from cross-contamination in the lab rather than from patient infections.

Lack of evidence for a role of xenotropic murine leukemia virus-related virus in the pathogenesis of prostate cancer and/or chronic fatigue syndrome.

Hong, Ping, Li, Jinming·Virus research·2012

A virus called XMRV was once thought to possibly cause ME/CFS and prostate cancer, but this review found no solid evidence supporting that connection. The authors looked at multiple studies and concluded that most positive findings were likely due to contamination in lab samples, not actual infection. This virus does not appear to play a role in causing ME/CFS.

Peripheral and central mechanisms of fatigue in inflammatory and noninflammatory rheumatic diseases.

Staud, Roland·Current rheumatology reports·2012

Fatigue in rheumatic diseases like ME/CFS, fibromyalgia, and lupus comes from both physical body problems and mental/central nervous system factors, not just one or the other. Doctors can measure physical fatigue through muscle tests and mental fatigue through questionnaires. Importantly, pain and mood problems are often stronger predictors of fatigue than the disease activity itself, and treatments for both medication and lifestyle changes can help.

Pain and Sensitization

E3 PreliminaryBehavioralPEM not requiredCross-Sectional

A role for corticosteroid-binding globulin variants in stress-related disorders.

Marathe, Chinmay S, Torpy, David J·Expert review of endocrinology & metabolism·2012

This review examines how genetic variations in a protein called corticosteroid-binding globulin (CBG) may influence whether someone develops ME/CFS, fibromyalgia, or chronic pain. CBG helps transport cortisol (the body's stress hormone) in the blood, and when this protein doesn't work properly, it may affect how the body responds to stress. The researchers looked at evidence from genetic studies and animal models suggesting that inherited differences in the CBG gene could increase someone's risk of developing these stress-related conditions.

Endocrine Disruption

Metacognitive factors in chronic fatigue syndrome.

Maher-Edwards, Lorraine, Fernie, Bruce A, Murphy, Gabrielle et al.·Clinical psychology & psychotherapy·2012

This study explored how ME/CFS patients think about their thinking—specifically, their beliefs about analyzing and solving problems related to their symptoms. Researchers found that patients have both helpful and unhelpful thoughts about trying to understand their illness, and they often focus on either distracting themselves or monitoring their symptoms closely. The study suggests that these thought patterns may play a role in how ME/CFS symptoms develop or persist.

Cognitive Impairment

The tale of xenotropic murine leukemia virus-related virus.

Groom, Harriet C T, Bishop, Kate N·The Journal of general virology·2012

In 2009, scientists announced they found a virus called XMRV in many ME/CFS patients, raising hopes for a breakthrough. However, when other researchers tried to repeat these findings, they couldn't find the virus in patient samples. By 2011, it became clear that the original samples were contaminated, meaning the virus had accidentally been introduced during testing rather than being present in patients naturally. This review explains how this scientific discovery turned out to be a false alarm.

Biological underpinnings of the commonalities in depression, somatization, and Chronic Fatigue Syndrome.

Anderson, George, Maes, Michael, Berk, Michael·Medical hypotheses·2012

This review examines why people with ME/CFS, depression, and somatization (a condition involving unexplained body symptoms) often experience similar physical symptoms like fatigue, pain, and autonomic problems. The researchers found evidence that these symptoms arise from real biological changes in the body, including immune system activation and changes in how the body processes an amino acid called tryptophan. This suggests these seemingly different conditions may share common biological pathways rather than being purely psychological.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Abnormal endogenous pain modulation is a shared characteristic of many chronic pain conditions.

Staud, Roland·Expert review of neurotherapeutics·2012

People with chronic pain often have trouble turning off pain signals in their brain and spinal cord, even when they should. This review explains that many chronic pain conditions—including ME/CFS—share a common problem: their bodies amplify pain signals instead of suppressing them. Tests can measure how well someone's natural pain-blocking system works, and these tests might help predict who will develop chronic pain.

Pain and Sensitization

Role of Lactobacillus acidophilus loaded floating beads in chronic fatigue syndrome: behavioral and biochemical evidences.

Singh, P K, Chopra, K, Kuhad, A et al.·Neurogastroenterology and motility·2012

This study tested whether a beneficial bacteria called Lactobacillus acidophilus could help reduce fatigue symptoms in rats. Researchers created extreme fatigue in rats through repeated exhausting swimming, then gave some rats either the bacteria alone or the bacteria packaged in special beads designed to survive digestion. The bacteria treatment reduced fatigue-like behavior and improved markers of inflammation and immune system stress.

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Linking disease symptoms and subtypes with personalized systems-based phenotypes: a proof of concept study.

Aschbacher, Kirstin, Adam, Emma K, Crofford, Leslie J et al.·Brain, behavior, and immunity·2012

This study examined how the body's stress-response system (the HPA axis) works differently in people with ME/CFS and fibromyalgia compared to healthy people. Researchers measured stress hormones (cortisol and ACTH) every 10 minutes for 24 hours and used computer modeling to understand each person's unique hormone patterns. They found that nighttime hormone patterns were different in patients versus healthy controls, and these patterns were linked to symptoms like pain, fatigue, and poor sleep.

Sleep

E3 PreliminaryCohortPEM not requiredCase-Control

Improved chronic fatigue symptoms after removal of mercury in patient with increased mercury concentration in hair toxic mineral assay: a case.

Shin, Sae-Ron, Han, A-Lum·Korean journal of family medicine·2012

This case report describes one patient whose chronic fatigue symptoms improved after receiving treatment to remove mercury from their body. The patient had eaten large amounts of raw tuna, which can contain mercury, and testing showed mercury levels in their hair that were higher than normal but below what's considered poisoning. After mercury removal therapy, the patient's fatigue got better.

E3 PreliminaryGuidelinePEM not requiredGuideline

[Persistent fatigue following Q fever].

Keijmel, Stephan P, Morroy, Gabriëlla, Delsing, Corine E et al.·Nederlands tijdschrift voor geneeskunde·2012

After a bacterial infection called Q fever, about 1 in 5 patients develop long-lasting fatigue and other symptoms called Q fever fatigue syndrome (QFS). This guideline from the Netherlands helps doctors diagnose and treat QFS consistently. Many patients recover on their own within six months, but those who don't may benefit from cognitive behavioral therapy, a type of talk therapy that helps people manage chronic fatigue.

Diagnostics

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Live sequence charts to model medical information.

Aslakson, Eric, Szekely, Smadar, Vernon, Suzanne D et al.·Theoretical biology & medical modelling·2012

Researchers developed a new way to organize and understand patient medical records by translating written descriptions of illness into visual diagrams. They tested this approach using an actual patient interview with someone who was later diagnosed with ME/CFS. This method could help doctors and researchers better track how diseases develop over time and identify important patterns in patient histories.

Zinc-finger antiviral protein inhibits XMRV infection.

Wang, Xinlu, Tu, Fan, Zhu, Yiping et al.·PloS one·2012

This study investigates how a human immune protein called ZAP (zinc-finger antiviral protein) blocks a virus called XMRV from multiplying in cells. Researchers found that when cells produce more ZAP, XMRV cannot spread effectively, and when ZAP levels are reduced, cells become more vulnerable to the virus. The study shows that ZAP works by targeting and destroying the virus's genetic instructions before they can be used to make new virus particles.