Evidence browser

Pain and SensitizationBiomarkers

Increased Vulnerability to Pattern-Related Visual Stress in Myalgic Encephalomyelitis.

Wilson, Rachel L, Paterson, Kevin B, Hutchinson, Claire V·Perception·2015

This study tested whether people with ME/CFS experience more visual discomfort when looking at certain patterns compared to healthy people. Forty participants (20 with ME/CFS and 20 without) viewed three different striped patterns and reported how distorted or uncomfortable they looked. People with ME/CFS reported significantly more visual distortion, especially when viewing medium-frequency patterns, suggesting their eyes and brains may process visual information differently.

E2 ModerateCohortPEM unclearLongitudinal

Longitudinal analysis of immune abnormalities in varying severities of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis patients.

Hardcastle, Sharni Lee, Brenu, Ekua Weba, Johnston, Samantha et al.·Journal of translational medicine·2015

This study tracked immune system changes in 42 ME/CFS patients (divided into moderate and severe groups) and 18 healthy controls over 6 months. Researchers used blood tests to count different types of immune cells. They found that people with severe ME/CFS had noticeably different immune cell patterns than those with moderate ME/CFS or healthy controls, suggesting the immune system may work differently depending on how severe the illness is.

E2 ModerateCohortPEM requiredCross-Sectional

A new case definition of Neuro-Inflammatory and Oxidative Fatigue (NIOF), a neuroprogressive disorder, formerly known as chronic fatigue syndrome or Myalgic Encephalomyelitis: results of multivariate pattern recognition methods and external validation by neuro-immune biomarkers.

Maes, Michael·Neuro endocrinology letters·2015

This study looked at whether ME/CFS could be better understood by examining specific blood markers related to inflammation, oxidative stress, and immune activation. Researchers found two distinct groups of people with chronic fatigue—one group had significantly higher levels of problematic immune markers and inflammatory signs. The study proposes a new way to identify ME/CFS based on fatigue plus at least four of these symptoms: muscle tension, memory problems, sleep issues, digestive problems, headaches, or flu-like feelings.

E2 ModerateCohortPEM requiredCase-Control

Submaximal exercise testing with near-infrared spectroscopy in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients compared to healthy controls: a case-control study.

Miller, Ruth R, Reid, W Darlene, Mattman, Andre et al.·Journal of translational medicine·2015

This study tested whether a simple hand-squeezing exercise combined with a special infrared light tool could help identify ME/CFS in patients. Researchers compared 16 people with ME/CFS to 16 healthy people and measured how well oxygen was being used in their muscles during the test. People with ME/CFS showed different patterns of oxygen use and reported feeling more tired during the exercise, even though they were squeezing with less force.

BiomarkersPost-Exertional Malaise

Cytokine expression provides clues to the pathophysiology of Gulf War illness and myalgic encephalomyelitis.

Khaiboullina, Svetlana F, DeMeirleir, Kenny L, Rawat, Shanti et al.·Cytokine·2015

This study looked at chemical messengers in the blood called cytokines to understand Gulf War illness (GWI) and ME/CFS better. Researchers found that certain cytokines could identify ME/CFS patients very well, but were less reliable for GWI patients. The findings suggest that while GWI and ME/CFS share many similar symptoms, they may have different underlying immune system problems.

E2 ModerateCohortPEM unclearObservational

Distinct plasma immune signatures in ME/CFS are present early in the course of illness.

Hornig, Mady, Montoya, José G, Klimas, Nancy G et al.·Science advances·2015

This study found that people with ME/CFS have distinctive patterns of immune system markers in their blood, but only early in the disease. Researchers compared blood samples from 52 people with early-stage ME/CFS to 348 healthy people and 246 people with long-standing ME/CFS. The early-stage group showed heightened immune activity that was not present in people who had been sick longer, suggesting the disease's immune profile changes over time.

E2 ModerateCohortPEM not requiredLongitudinal

The MAPP research network: design, patient characterization and operations.

Landis, J Richard, Williams, David A, Lucia, M Scott et al.·BMC urology·2014

The MAPP Research Network is a large study designed to understand chronic pelvic pain conditions and related illnesses like fibromyalgia, chronic fatigue syndrome, and irritable bowel syndrome. Researchers followed over 1,000 patients at six sites across the United States, collecting detailed information about their symptoms, blood samples, and brain imaging to identify what causes these conditions and how they connect to each other.

Use of single-nucleotide polymorphisms (SNPs) to distinguish gene expression subtypes of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME).

Shimosako, Nana, Kerr, Jonathan R·Journal of clinical pathology·2014

This study looked at small variations in DNA (called SNPs) from people with ME/CFS to see if these genetic differences could help identify different subtypes of the condition. Researchers compared DNA from 108 ME/CFS patients with 17 people with depression and 68 healthy people. They found that certain genetic variations were more common in ME/CFS patients and that different combinations of these variations appeared to match different subtypes of the illness.

Multiscale analysis of heart rate variability in non-stationary environments.

Gao, Jianbo, Gurbaxani, Brian M, Hu, Jing et al.·Frontiers in physiology·2013

This study looked at how the heart rate patterns of people with ME/CFS differ from healthy people, especially when they're under stress. Researchers used advanced computer methods to analyze heart rate data collected during a social stress test. They found that before the stress test, people with ME/CFS had noticeably different heart rate patterns than healthy controls, but these differences became smaller during the stress test itself.

NMR metabolic profiling of serum identifies amino acid disturbances in chronic fatigue syndrome.

Armstrong, Christopher W, McGregor, Neil R, Sheedy, John R et al.·Clinica chimica acta; international journal of clinical chemistry·2012

Researchers used a specialized blood test called NMR to compare the levels of different chemicals in the blood of 11 people with ME/CFS and 10 healthy people. They found that people with ME/CFS had significantly lower levels of two amino acids (building blocks of protein): glutamine and ornithine. These findings suggest that people with ME/CFS may have problems with how their bodies process certain proteins and manage nitrogen, which are important for energy and cell function.

E2 ModerateCohortPEM requiredCross-Sectional

Myalgic Encephalomyelitis (ME), Chronic Fatigue Syndrome (CFS), and Chronic Fatigue (CF) are distinguished accurately: results of supervised learning techniques applied on clinical and inflammatory data.

Maes, Michael, Twisk, Frank N M, Johnson, Cort·Psychiatry research·2012

This study looked at whether ME, CFS, and chronic fatigue are truly different conditions or if they overlap too much to distinguish. Researchers tested 144 patients and found that post-exertional malaise (PEM)—where symptoms worsen after activity—is a key feature that separates ME from CFS. They also found that ME and CFS patients had higher levels of certain inflammatory markers in their blood compared to people with simple chronic fatigue.

BiomarkersImmune SystemPost-Exertional Malaise

Visible and near-infrared spectra collected from the thumbs of patients with chronic fatigue syndrome for diagnosis.

Sakudo, Akikazu, Kuratsune, Hirohiko, Kato, Yukiko Hakariya et al.·Clinica chimica acta; international journal of clinical chemistry·2012

Researchers used a special light-based scanner on patients' thumbs to see if they could tell the difference between people with ME/CFS and healthy people. The scanner detected subtle changes in how light passes through the skin in a specific wavelength range. When they analyzed the results using computer models, they were able to correctly identify about 70% of ME/CFS patients and 83% of healthy people, suggesting this method might someday help doctors diagnose ME/CFS more objectively.

Superiority of 18F-FDG PET compared to 111In-labelled leucocyte scintigraphy in the evaluation of fever of unknown origin.

Seshadri, N, Sonoda, L I, Lever, A M et al.·The Journal of infection·2012

This study compared two imaging tests for finding the cause of fever that doctors can't explain. One test (PET) was much better at detecting problems—finding a cause in 86% of patients—compared to the other test (leucocyte scintigraphy), which only found a cause in 20% of patients. PET scans successfully identified infections, inflammation, and other conditions causing unexplained fevers.

Failure to Detect XMRV-Specific Antibodies in the Plasma of CFS Patients Using Highly Sensitive Chemiluminescence Immunoassays.

Oakes, Brendan, Qiu, Xiaoxing, Levine, Susan et al.·Advances in virology·2011

In 2009, researchers claimed they found a virus called XMRV in most ME/CFS patients' blood. This study tested whether that finding was real by looking for antibodies (immune system markers) to XMRV in blood samples from ME/CFS patients and healthy people. The researchers found no evidence of XMRV antibodies in any of the samples, suggesting the original finding may not have been accurate.

Immunological abnormalities as potential biomarkers in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Brenu, Ekua W, van Driel, Mieke L, Staines, Don R et al.·Journal of translational medicine·2011

This study examined immune system markers in 95 ME/CFS patients compared to 50 healthy people to see if certain blood tests could help diagnose the condition. Researchers found that ME/CFS patients had imbalanced immune responses, including higher levels of certain inflammatory proteins and lower activity of immune cells that normally fight infections. These immune differences might one day be used as reliable diagnostic markers to help doctors identify ME/CFS.

Increased plasma peroxides as a marker of oxidative stress in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

Maes, Michael, Kubera, Marta, Uytterhoeven, Marc et al.·Medical science monitor : international medical journal of experimental and clinical research·2011

This study measured two markers of oxidative stress (damage caused by harmful molecules in the body) in people with ME/CFS compared to healthy people. Researchers found that ME/CFS patients had significantly higher levels of plasma peroxides—harmful molecules that damage cells. These findings suggest that oxidative stress may play a role in ME/CFS, which could help explain some of the illness's symptoms.

Assessment of a 44 gene classifier for the evaluation of chronic fatigue syndrome from peripheral blood mononuclear cell gene expression.

Frampton, Daniel, Kerr, Jonathan, Harrison, Tim J et al.·PloS one·2011

Researchers tested whether 44 genes could be used together to diagnose ME/CFS by measuring their activity in blood samples from patients and healthy people. While the combination of genes worked well when tested on the original group, it failed when applied to a new group of patients, correctly identifying only about two-thirds of cases. This suggests that a simple blood test using these genes is not yet ready for diagnosing ME/CFS in everyday medical practice.

Lower whole blood glutathione peroxidase (GPX) activity in depression, but not in myalgic encephalomyelitis / chronic fatigue syndrome: another pathway that may be associated with coronary artery disease and neuroprogression in depression.

Maes, Michael, Mihaylova, Ivanka, Kubera, Marta et al.·Neuro endocrinology letters·2011

This study looked at a protective enzyme called GPX that helps defend cells from damage in people with depression and ME/CFS. The researchers found that people with depression had lower levels of this enzyme compared to healthy people, but people with ME/CFS had normal levels. Both groups showed connections between low enzyme levels and symptoms like mood problems and autonomic nervous system dysfunction.

The increase of alpha-melanocyte-stimulating hormone in the plasma of chronic fatigue syndrome patients.

Shishioh-Ikejima, Nobue, Ogawa, Tokiko, Yamaguti, Kouzi et al.·BMC neurology·2010

Researchers measured a hormone called alpha-MSH in the blood of 55 ME/CFS patients and compared it to 30 healthy people. They found that patients diagnosed within the last 5 years had significantly higher alpha-MSH levels than healthy controls, but this difference disappeared in patients who had been ill longer. This suggests alpha-MSH might be a useful blood test for identifying ME/CFS in newly diagnosed patients.

Increased ventricular lactate in chronic fatigue syndrome measured by 1H MRS imaging at 3.0 T. II: comparison with major depressive disorder.

Murrough, James W, Mao, Xiangling, Collins, Katherine A et al.·NMR in biomedicine·2010

This study used a special type of brain imaging called MRI to measure a substance called lactate in the fluid around the brain of people with ME/CFS. The researchers found that people with ME/CFS had significantly higher lactate levels compared to healthy people and people with depression. Interestingly, people with depression had normal lactate levels, suggesting this finding may be specific to ME/CFS and not just a symptom of mental illness.