ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

21–38 of 38 studies

E2 ModeratePEM not requiredPreliminaryCase-ControlEditor reviewed

Increased d-lactic Acid intestinal bacteria in patients with chronic fatigue syndrome.

Sheedy, John R, Wettenhall, Richard E H, Scanlon, Denis et al.·In vivo (Athens, Greece)·2009

This study found that people with ME/CFS have higher levels of specific bacteria in their gut that produce a substance called D-lactic acid. These bacteria were found in much larger quantities in stool samples from ME/CFS patients compared to healthy people. The researchers suggest this excess D-lactic acid might help explain why some ME/CFS patients experience brain fog and cognitive problems.

Gut MicrobiomeEnergy Metabolism

E3 PreliminaryPEM not requiredPreliminaryMethods-PaperEditor reviewed

Profiling Antibody Reactivity to Gut Microbes in ME/CFS Patients.

Seton, Katharine A, Carding, Simon R·Methods in molecular biology (Clifton, N.J.)·2025

This study looks at how the immune system of ME/CFS patients reacts to bacteria in the gut. Many ME/CFS patients have changes in their gut bacteria and a leaky gut lining that allows bacteria and their toxic products to enter the bloodstream, potentially triggering widespread inflammation. The researchers developed methods to measure specific immune proteins (antibodies) that ME/CFS patients produce in response to these gut bacteria, compared to healthy household members.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryCross-SectionalEditor reviewed

Dysregulation of the Kynurenine Pathway, Cytokine Expression Pattern, and Proteomics Profile Link to Symptomology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Kavyani, Bahar, Ahn, Seong Beom, Missailidis, Daniel et al.·Molecular neurobiology·2024

This study found that ME/CFS patients have imbalances in a particular chemical pathway in their body (the kynurenine pathway) that appears connected to inflammation and symptom severity. The researchers discovered that higher levels of one early chemical in this pathway correlated with worse symptoms, while lower levels of later chemicals in the pathway might affect how cells produce energy. Interestingly, they also found that five of the most significantly changed proteins in ME/CFS patients are involved in gut health, suggesting the gut microbiome may play an important role in the disease.

BiomarkersGut MicrobiomeEnergy MetabolismImmune System

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

The Gut Microbiome and Symptom Burden After Kidney Transplantation: An Overview and Research Opportunities.

Lockwood, Mark B, Sung, Choa, Alvernaz, Suzanne A et al.·Biological research for nursing·2024

Kidney transplant patients often feel very tired and sick even after their new kidney works well. Scientists think the bacteria living in our digestive system might explain why this happens. Transplant medications can change these helpful bacteria, which may affect how our immune system, hormones, and brain work together. This article explores how fixing the gut bacteria might help transplant patients feel better.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryMethods-PaperEditor reviewed

KombOver: Efficient k-core and K-truss based characterization of perturbations within the human gut microbiome.

Sapoval, Nicolae, Tanevski, Marko, Treangen, Todd J·Pacific Symposium on Biocomputing. Pacific Symposium on Biocomputing·2024

This study describes a new computer tool called KombOver that analyzes bacteria in the gut more efficiently than previous methods. Researchers tested it on nearly 1,000 gut samples from people with ME/CFS and other conditions to see how microbial communities change in response to illness. The tool works much faster and requires less computing power than earlier versions, making it more practical for large research studies.

Gut Microbiome

E3 PreliminaryPEM not requiredPreliminaryMechanisticEditor reviewed

Integrated 'omics analysis for the gut microbiota response to moxibustion in a rat model of chronic fatigue syndrome.

Chaoran, L I, Yan, Yang, Chuwen, Feng et al.·Journal of traditional Chinese medicine = Chung i tsa chih ying wen pan·2023

This study tested whether moxibustion (a traditional Chinese medicine technique using heat) could help treat chronic fatigue syndrome in rats. Researchers found that moxibustion improved fatigue-like symptoms and restored balance to the gut bacteria and chemical levels that were abnormal in fatigued rats. The results suggest that moxibustion may work by fixing problems in the gut microbiome (bacteria) and the metabolites (chemical byproducts) they produce.

Gut Microbiome

E3 PreliminaryPEM not requiredPreliminaryMechanisticEditor reviewed

Investigating the Human Intestinal DNA Virome and Predicting Disease-Associated Virus-Host Interactions in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Hsieh, Shen-Yuan, Savva, George M, Telatin, Andrea et al.·International journal of molecular sciences·2023

This study looked at viruses living in the gut of people with severe ME/CFS and compared them to healthy people. The researchers found that people with ME/CFS have different types and amounts of viruses in their intestines, and they identified specific viruses that might interact with gut bacteria in ways that could be linked to the disease. This research provides a starting point for understanding whether these intestinal viruses might play a role in ME/CFS.

Gut Microbiome

E3 PreliminaryPEM not requiredPreliminaryMechanisticEditor reviewed

Astragalus polysaccharide ameliorated complex factor-induced chronic fatigue syndrome by modulating the gut microbiota and metabolites in mice.

Wei, Xintong, Xin, Jiayun, Chen, Wei et al.·Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie·2023

This study tested whether astragalus polysaccharide (APS), a compound from traditional Chinese medicine, could help with chronic fatigue syndrome in mice. The researchers found that APS improved fatigue-related symptoms by changing the bacteria in the gut, which led to more production of beneficial compounds called short-chain fatty acids that reduced inflammation and oxidative stress in the brain.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryObservationalEditor reviewed

Causal Effects between Gut Microbiome and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Two-Sample Mendelian Randomization Study.

He, Gang, Cao, Yu, Ma, Honghao et al.·Frontiers in microbiology·2023

This study used genetic analysis to investigate whether changes in gut bacteria might actually cause ME/CFS, rather than just being associated with it. Researchers found that two types of bacteria—Paraprevotella and Ruminococcaceae_UCG_014—appear to increase the risk of developing ME/CFS. These findings suggest that gut bacteria may play a role in how ME/CFS develops.

Gut MicrobiomeImmune System

E3 PreliminaryPEM not requiredPreliminaryReview-NarrativeEditor reviewed

[Mechanism of acupuncture and moxibustion in treatment of chronic fatigue syndrome from perspective of intestinal flora].

Li, Chao-Ran, Sun, Zhong-Ren, Wang, Yu-Lin et al.·Zhongguo zhen jiu = Chinese acupuncture & moxibustion·2022

This study explores how gut bacteria may contribute to chronic fatigue syndrome and suggests that acupuncture and moxibustion (traditional Chinese medicine techniques) might help by restoring healthy gut bacteria. The researchers believe that an imbalance in gut bacteria can trigger inflammation and metabolism problems in ME/CFS patients, and that these traditional treatments could reduce fatigue by improving gut health and communication between the gut and brain.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Mucosal Immunity and the Gut-Microbiota-Brain-Axis in Neuroimmune Disease.

Sterling, Kathryn G, Dodd, Griffin Kutler, Alhamdi, Shatha et al.·International journal of molecular sciences·2022

This review article examines the connection between gut bacteria, immunity, and the brain in diseases like ME/CFS. The authors explain that the bacteria in our gut can communicate with our brain through chemical signals and nerves, but this communication can be disrupted in certain illnesses. They focus on how the immune system in the gut lining controls which bacteria thrive there, and how changes in these bacterial communities might contribute to neuroimmune diseases.

NeuroinflammationGut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryMethods-PaperEditor reviewed

Establishment and evaluation of prediction model for multiple disease classification based on gut microbial data.

Bang, Sohyun, Yoo, DongAhn, Kim, Soo-Jin et al.·Scientific reports·2019

Researchers used artificial intelligence to analyze bacteria in the gut of patients with six different diseases, including ME/CFS, to see if gut bacteria patterns could help identify which disease a person has. They tested different computer learning methods and found that looking at bacteria at the genus level (a specific classification of microorganisms) worked best, and they identified certain bacterial groups that might serve as disease markers.

BiomarkersGut Microbiome

E3 PreliminaryPEM requiredPreliminaryCase-ControlEditor reviewed

A Pair of Identical Twins Discordant for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Differ in Physiological Parameters and Gut Microbiome Composition.

Giloteaux, Ludovic, Hanson, Maureen R, Keller, Betsy A·The American journal of case reports·2016

This study compared two identical twins—one with ME/CFS and one without—to understand what causes the illness. The affected twin showed reduced exercise capacity, abnormal responses to physical exertion, and differences in immune markers and gut bacteria compared to the healthy twin. These findings suggest that ME/CFS involves problems with how the body responds to exercise and changes in the gut bacteria that may trigger inflammation.

Gut MicrobiomeImmune SystemPost-Exertional Malaise

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

Fecal Microbiota Transplantation and Its Usage in Neuropsychiatric Disorders.

Evrensel, Alper, Ceylan, Mehmet Emin·Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology·2016

This review examines fecal microbiota transplantation (FMT)—a treatment where healthy gut bacteria from a donor are transferred to a patient—and its potential use in treating brain and mental health conditions. While FMT is already proven effective for certain gut infections and inflammatory bowel diseases, researchers are exploring whether it might help with conditions like ME/CFS, autism, and Parkinson's disease. Early results are promising, but much more research is needed to understand if it's safe and effective long-term.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

The Role of Toll-Like Receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A New Promising Therapeutic Approach?

Gambuzza, Maria Elsa, Salmeri, Francesca Maria, Soraci, Luca et al.·CNS & neurological disorders drug targets·2015

This review examines how certain immune system sensors called Toll-like receptors (TLRs) may contribute to ME/CFS. These receptors sit on cells in the gut and detect bacteria and other microbes, triggering inflammation that may spread to the brain and cause fatigue and other symptoms. The researchers suggest that targeting these TLRs with new medications might help reduce inflammation and improve symptoms.

NeuroinflammationGut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryReview-NarrativeEditor reviewed

The gut microbiome and the brain.

Galland, Leo·Journal of medicinal food·2014

Your gut bacteria can communicate with your brain in several ways: they produce substances that trigger your immune system, create chemicals that affect your mood and sleep, and send signals directly to your brain through a major nerve called the vagus nerve. When the balance of gut bacteria is disrupted, this communication can go wrong and may contribute to problems like chronic fatigue, brain fog, and mood changes.

NeuroinflammationGut MicrobiomeImmune System

E3 PreliminaryPEM unclearWeak / uncertainReview-NarrativeEditor reviewed

[Pathogenicity of fungi in the intestines--current status of the discussion].

Scheurlen, M·Fortschritte der Medizin·1996

Some people believe that yeast infections in the gut, particularly from a fungus called Candida, might cause chronic fatigue syndrome and other long-term illnesses by producing harmful toxins. However, experts disagree about whether this theory is actually true. This editorial explains that while the idea is interesting, there isn't enough solid scientific evidence yet to prove it works or to recommend yeast-fighting treatments based on this theory alone.

Gut MicrobiomeImmune System

E3 PreliminaryPEM unclearPreliminaryMechanisticMachine-drafted

A metagenomic approach to investigate the microbial causes of myalgic encephalomyelitis/chronic fatigue syndrome: moving beyond XMRV.

Miller, Ruth R, Gardy, Jennifer L, Tang, Patrick et al.·Fatigue : biomedicine, health & behavior·2013

This study used advanced genetic sequencing techniques to search for microorganisms (bacteria, viruses, and fungi) that might cause ME/CFS. Rather than looking for one specific virus, the researchers cast a wider net to detect any microbes present in patient samples. This approach moved beyond previous unsuccessful searches for a single virus, offering a more comprehensive way to understand whether infections play a role in ME/CFS.

Gut Microbiome

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Increased d-lactic Acid intestinal bacteria in patients with chronic fatigue syndrome.

Profiling Antibody Reactivity to Gut Microbes in ME/CFS Patients.

Dysregulation of the Kynurenine Pathway, Cytokine Expression Pattern, and Proteomics Profile Link to Symptomology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

The Gut Microbiome and Symptom Burden After Kidney Transplantation: An Overview and Research Opportunities.

KombOver: Efficient k-core and K-truss based characterization of perturbations within the human gut microbiome.

Integrated 'omics analysis for the gut microbiota response to moxibustion in a rat model of chronic fatigue syndrome.

Investigating the Human Intestinal DNA Virome and Predicting Disease-Associated Virus-Host Interactions in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Astragalus polysaccharide ameliorated complex factor-induced chronic fatigue syndrome by modulating the gut microbiota and metabolites in mice.

Causal Effects between Gut Microbiome and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Two-Sample Mendelian Randomization Study.

[Mechanism of acupuncture and moxibustion in treatment of chronic fatigue syndrome from perspective of intestinal flora].

Mucosal Immunity and the Gut-Microbiota-Brain-Axis in Neuroimmune Disease.

Establishment and evaluation of prediction model for multiple disease classification based on gut microbial data.

A Pair of Identical Twins Discordant for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Differ in Physiological Parameters and Gut Microbiome Composition.

Fecal Microbiota Transplantation and Its Usage in Neuropsychiatric Disorders.

The Role of Toll-Like Receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A New Promising Therapeutic Approach?

The gut microbiome and the brain.

[Pathogenicity of fungi in the intestines--current status of the discussion].

A metagenomic approach to investigate the microbial causes of myalgic encephalomyelitis/chronic fatigue syndrome: moving beyond XMRV.

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