Evidence browser

Circulating miRNAs Expression in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Soffritti, Irene, Gravelsina, Sabine, D'Accolti, Maria et al.·International journal of molecular sciences·2023

Researchers tested whether six small molecules called microRNAs (miRNAs) in the blood could help identify people with ME/CFS. They compared blood samples from 40 ME/CFS patients with 20 healthy people and found that five miRNAs were more abundant in patients' blood while one was less abundant. Interestingly, the levels of these molecules matched how severe each patient's symptoms were, suggesting they could potentially be used as a blood test to help diagnose ME/CFS.

Distinguishing features of long COVID identified through immune profiling.

Klein, Jon, Wood, Jamie, Jaycox, Jillian R et al.·Nature·2023

Researchers studied 275 people with and without long COVID to understand what happens in the immune system. They found that people with long COVID have different patterns of immune cells and antibodies, including stronger responses to past viral infections like Epstein-Barr virus, and lower levels of the stress hormone cortisol. Using computer analysis, they identified specific immune markers that could help identify who has long COVID.

Evidence of a Novel Mitochondrial Signature in Systemic Sclerosis Patients with Chronic Fatigue Syndrome.

van Eeden, Charmaine, Redmond, Desiree, Mohazab, Naima et al.·International journal of molecular sciences·2023

This study looked at people with a connective tissue disease called systemic sclerosis who also experience severe fatigue (ME/CFS symptoms). Researchers found that fatigued patients had different patterns in how their cells' energy-producing structures (mitochondria) work compared to non-fatigued patients. These differences involved specific genes related to energy production, suggesting that measuring these genes might help doctors identify which systemic sclerosis patients have ME/CFS.

E2 ModerateCohortPEM requiredLongitudinal

One-year follow-up of young people with ME/CFS following infectious mononucleosis by Epstein-Barr virus.

Pricoco, Rafael, Meidel, Paulina, Hofberger, Tim et al.·Frontiers in pediatrics·2023

This study followed 25 young people (12 teenagers and 13 young adults) who developed ME/CFS after having infectious mononucleosis caused by Epstein-Barr virus. Researchers checked on their symptoms and quality of life at the start, 6 months, and 12 months later. Teenagers showed better improvement over the year, with more than half no longer meeting ME/CFS criteria, while young adults continued to have severe symptoms with little improvement.

Severe MEBiomarkersPost-Exertional Malaise

A Causal-Pathway Phenotype of Chronic Fatigue Syndrome due to Hemodialysis in Patients with End-Stage Renal Disease.

Asad, Halah Nori, Al-Hakeim, Hussein Kadhem, Moustafa, Shatha Rouf et al.·CNS & neurological disorders drug targets·2023

This study looked at patients with severe kidney disease who need dialysis (a machine that cleans their blood) and found they often experience extreme fatigue and other symptoms similar to ME/CFS, such as muscle pain, sleep problems, and brain fog. Researchers measured various substances in the blood and found that fatigue was linked to anemia (low blood iron), poor nutrition, and certain protein imbalances caused by the dialysis treatment itself. The more dialysis sessions patients needed, the worse their fatigue tended to be.

E2 ModerateCohortPEM requiredLongitudinal

Long-term symptom severity and clinical biomarkers in post-COVID-19/chronic fatigue syndrome: results from a prospective observational cohort.

Legler, Franziska, Meyer-Arndt, Lil, Mödl, Lukas et al.·EClinicalMedicine·2023

This study followed 106 people with long-term fatigue after COVID-19 for up to 20 months to see how they recovered over time. Researchers found that some patients met the diagnostic criteria for ME/CFS and had persistent, severe symptoms including fatigue and post-exertional malaise (worsening after activity), while others improved more substantially. Lower muscle strength at the start of illness was linked to ongoing symptoms, especially in those with ME/CFS.

BiomarkersImmune SystemPost-Exertional Malaise

Circulating microRNA expression signatures accurately discriminate myalgic encephalomyelitis from fibromyalgia and comorbid conditions.

Nepotchatykh, Evguenia, Caraus, Iurie, Elremaly, Wesam et al.·Scientific reports·2023

Researchers studied tiny molecules called microRNAs in the blood to see if they could tell the difference between ME/CFS, fibromyalgia, and people who have both conditions. They found that each condition has a unique pattern of these microRNAs, like a biological fingerprint. Using these patterns, they created a computer model that could accurately identify which condition a person has, which could help with proper diagnosis.

E2 ModerateCohortPEM requiredCross-Sectional

Exploring the joint potential of inflammation, immunity, and receptor-based biomarkers for evaluating ME/CFS progression.

Berkis, Uldis, Svirskis, Simons, Krumina, Angelika et al.·Frontiers in immunology·2023

This study looked for blood markers that could help doctors understand how severe ME/CFS is and track disease progression. Researchers measured inflammation-related proteins, immune system components, and antibodies against nerve receptors in blood samples from healthy people and patients with mild, moderate, and severe ME/CFS. They found that certain markers—especially antibodies against beta2-adrenergic and M4 receptors, along with specific immune proteins—showed promise for distinguishing disease severity, with over 90% accuracy in identifying who has ME/CFS versus who is healthy.

NeuroinflammationBiomarkers

The physio-affective phenome of major depression is strongly associated with biomarkers of astroglial and neuronal projection toxicity which in turn are associated with peripheral inflammation, insulin resistance and lowered calcium.

Al-Hakeim, Hussein Kadhem, Al-Naqeeb, Tabarek Hadi, Almulla, Abbas F et al.·Journal of affective disorders·2023

This study examined whether brain and nerve damage markers in the blood are connected to depression symptoms and other physical complaints. Researchers measured several proteins in the blood of people with depression and compared them to healthy controls, finding that markers of brain cell and nerve damage—along with inflammation and insulin resistance—together explained about 61% of the severity of depression, anxiety, fatigue, and physical symptoms.

E2 ModerateCohortPEM not required

Metabolomic Evidence for Peroxisomal Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Che, Xiaoyu, Brydges, Christopher R, Yu, Yuanzhi et al.·International journal of molecular sciences·2022

Researchers found that people with ME/CFS have abnormal levels of certain fats and chemicals in their blood compared to healthy people. Specifically, they had lower levels of protective fats called plasmalogens and phospholipids, but higher levels of compounds called dicarboxylic acids. These chemical differences were so distinctive that a computer program could identify ME/CFS patients from their blood work with reasonable accuracy.

E2 ModerateCohortPEM unclearCase-Control

Revisiting IgG Antibody Reactivity to Epstein-Barr Virus in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Its Potential Application to Disease Diagnosis.

Sepúlveda, Nuno, Malato, João, Sotzny, Franziska et al.·Frontiers in medicine·2022

This study looked at antibody responses to Epstein-Barr virus (EBV), a common virus linked to ME/CFS onset in some patients. Researchers analyzed blood samples from 92 ME/CFS patients and 50 healthy people, testing reactions to over 3,000 EBV proteins. They found that in patients whose ME/CFS started after a suspected EBV infection, two specific viral proteins triggered stronger antibody responses than in healthy controls. These antibody patterns could correctly identify about 83% of infected patients and 72% of healthy people, suggesting they might become useful diagnostic markers.

Comparative Analysis of Extracellular Vesicles in Patients with Severe and Mild Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Bonilla, Hector, Hampton, Dylan, Marques de Menezes, Erika G et al.·Frontiers in immunology·2022

Researchers looked for tiny particles called extracellular vesicles in the blood of people with ME/CFS to see if they could help diagnose or understand the disease. They found that people with severe ME/CFS had higher levels of certain vesicles that come from B cells (immune cells) and platelets (blood clotting cells) compared to healthy people. While these differences were promising, they weren't strong enough to confirm they're reliable markers yet.

No difference in serum levels of B-cell activating receptor and antibodies against cytolethal distending toxin B and flagellin in post-infectious irritable bowel syndrome and chronic fatigue syndrome after Giardia infection.

Hanevik, Kurt, Saghaug, Christina, Aaland, Maren et al.·JGH open : an open access journal of gastroenterology and hepatology·2022

This study looked for three potential biological markers (BAFF, anti-CdtB, and anti-flagellin antibodies) in the blood of people who developed ME/CFS and/or IBS after a Giardia infection. Researchers compared these markers in patients to healthy controls but found no significant differences between the groups. The findings suggest these three markers are not useful for diagnosing ME/CFS or IBS.

E2 ModerateCohortPEM not requiredObservational

HERV-W ENV antigenemia and correlation of increased anti-SARS-CoV-2 immunoglobulin levels with post-COVID-19 symptoms.

Giménez-Orenga, Karen, Pierquin, Justine, Brunel, Joanna et al.·Frontiers in immunology·2022

This study found that a dormant virus-like element called HERV-W, which exists naturally in our DNA, may reactivate and remain active long after COVID-19 infection has cleared in people with long COVID. The researchers also discovered that people with higher levels of certain immune proteins (antibodies) against SARS-CoV-2, especially IgE antibodies, tended to have worse physical function. These findings suggest that HERV-W activation and lingering antibody responses might help explain why some people develop long-lasting COVID symptoms.

Autoimmune gene expression profiling of fingerstick whole blood in Chronic Fatigue Syndrome.

Wang, Zheng, Waldman, Michelle F, Basavanhally, Tara J et al.·Journal of translational medicine·2022

Researchers tested blood samples from 166 ME/CFS patients and 83 healthy people to look for immune system clues that might explain the disease. They found that six specific genes related to immune function were more active in patients with severe, bedridden ME/CFS compared to those with milder disease. The study suggests these genes could potentially be used as biomarkers to identify how severe someone's ME/CFS is and might point toward new treatments.

Post-COVID-19 Syndrome: Retinal Microcirculation as a Potential Marker for Chronic Fatigue.

Schlick, Sarah, Lucio, Marianna, Wallukat, Gerd et al.·International journal of molecular sciences·2022

Researchers studied whether tiny blood vessels in the eye could be a measurable sign of fatigue in people with long COVID. Using a special imaging technique to look at blood vessels in the retina (back of the eye), they found that people with long COVID—especially women—had reduced blood flow in these tiny vessels compared to healthy people. Those with long COVID who reported severe fatigue had even lower blood vessel density than those with milder fatigue, suggesting the eye scan might objectively confirm what patients report feeling.

E2 ModerateCohortPEM requiredProtocol

Multimodal MRI of myalgic encephalomyelitis/chronic fatigue syndrome: A cross-sectional neuroimaging study toward its neuropathophysiology and diagnosis.

Shan, Zack Y, Mohamed, Abdalla Z, Andersen, Thu et al.·Frontiers in neurology·2022

This study used advanced brain imaging to investigate whether ME/CFS is caused by a problem with how the brain's blood vessels respond to neural activity. Researchers scanned the brains of 288 people—including those with ME/CFS, chronic fatigue, fibromyalgia, and healthy controls—while they performed tasks and held their breath, measuring blood flow and brain chemicals. The goal was to find distinctive brain patterns that could objectively diagnose ME/CFS and understand what goes wrong in this disease.

Biomarkers in the diagnostic algorithm of myalgic encephalomyelitis/chronic fatigue syndrome.

Gravelsina, Sabine, Vilmane, Anda, Svirskis, Simons et al.·Frontiers in immunology·2022

This study looked for biological markers (measurable signs in the blood) that could help doctors diagnose ME/CFS more easily. Researchers tested 134 ME/CFS patients and 33 healthy people for a virus called HHV-6 and specific antibodies that attack nerve receptors. They found that ME/CFS patients had higher levels of certain antibodies compared to healthy controls, and patients with more virus in their blood tended to have more severe symptoms.

Analysis of Gender Differences in HRV of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Using Mobile-Health Technology.

Capdevila, Lluis, Castro-Marrero, Jesús, Alegre, José et al.·Sensors (Basel, Switzerland)·2021

Researchers used a smartphone app connected to a heart monitor to measure heart rate variability (how much the time between heartbeats varies) in ME/CFS patients and healthy people. They found that women with ME/CFS showed different heart patterns than healthy women, but men with ME/CFS did not show the same clear difference. This suggests that ME/CFS may affect the heart's nervous system control differently in men versus women.

Are Circulating Fibroblast Growth Factor 21 and N-Terminal Prohormone of Brain Natriuretic Peptide Promising Novel Biomarkers in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome?

Domingo, Joan Carles, Cordobilla, Begoña, Ferrer, Roser et al.·Antioxidants & redox signaling·2021

This study looked for new blood markers that could help identify ME/CFS by measuring two proteins called FGF21 and NT-proBNP in patients and healthy people. The researchers found that ME/CFS patients had significantly higher levels of both proteins and showed signs of increased inflammation and oxidative stress (cellular damage). These findings suggest these proteins might be useful tools for diagnosing ME/CFS or developing new treatments.