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Autoimmune Autonomic Dysfunction Syndromes: Potential Involvement and Pathophysiology Related to Complex Regional Pain Syndrome, Fibromyalgia, Chronic Fatigue Syndrome, Silicone Breast Implant-Related Symptoms and Post-COVID Syndrome.

Mahroum, Naim, Shoenfeld, Yehuda·Pathophysiology : the official journal of the International Society for Pathophysiology·2022

This article suggests that several chronic conditions—including ME/CFS, fibromyalgia, long COVID, and complex regional pain syndrome—may share a common cause: the immune system mistakenly producing antibodies that attack the autonomic nervous system (the part of your body that controls automatic functions like heart rate and blood pressure). The authors propose calling these conditions "autoimmune autonomic dysfunction syndromes" to highlight this shared mechanism and potentially help doctors diagnose and treat them more effectively.

E3 PreliminaryCohortPEM unclearCase-Control

Orthostatic intolerance as a potential contributor to prolonged fatigue and inconsistent performance in elite swimmers.

Petracek, Lindsay S, Eastin, Ella F, Rowe, Ian R et al.·BMC sports science, medicine & rehabilitation·2022

This study looked at five elite swimmers who experienced severe fatigue and couldn't perform at their usual level. The researchers tested whether orthostatic intolerance—a condition where the body struggles to maintain proper blood pressure when standing—might explain their symptoms. When the swimmers were tested with standing or tilt table tests, they all felt fatigued and other symptoms appeared. After receiving treatment with extra salt and fluids, all five swimmers felt significantly better and returned to normal performance.

E3 PreliminaryMechanismPEM not requiredObservational

Changes in the Allostatic Response to Whole-Body Cryotherapy and Static-Stretching Exercises in Chronic Fatigue Syndrome Patients vs. Healthy Individuals.

Kujawski, Sławomir, Bach, Anna M, Słomko, Joanna et al.·Journal of clinical medicine·2021

This study compared how the bodies of ME/CFS patients and healthy people respond to cold therapy combined with stretching exercises. Researchers measured fatigue, thinking ability, heart function, and nervous system activity before and after 10 sessions of treatment. They found that ME/CFS patients showed more disrupted connections between these body systems compared to healthy controls, suggesting their bodies struggle more to maintain balance under stress.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryMechanismPEM not requiredMechanistic

Homeostatic disturbance of thermoregulatory functions in rats with chronic fatigue.

Li, Danxi, Hu, Di, Shigeta, Mika et al.·Neuroscience research·2021

Many ME/CFS patients report feeling feverish or chilled even when their body temperature is normal. This study used rats with chronic fatigue to understand what goes wrong with the body's temperature control system. Researchers found that in early fatigue, the body tried to raise its temperature to cope, but over time this system broke down and stopped working properly, which may explain why fatigue becomes long-lasting.

E3 PreliminaryMechanismPEM not required

Deconditioning does not explain orthostatic intolerance in ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome).

van Campen, C Linda M C, Rowe, Peter C, Visser, Frans C·Journal of translational medicine·2021

This study examined whether being physically deconditioned (out of shape) causes the dizziness and fainting symptoms that many ME/CFS patients experience when standing up. Researchers tested 199 ME/CFS patients and 22 healthy people using exercise tests and a tilt table test that measures blood flow to the brain. The results showed that ME/CFS patients had significant problems with blood flow to their brain when tilted upright, but this problem occurred regardless of how deconditioned they were.

E3 PreliminaryMechanismPEM unclearCross-Sectional

Orthostatic stress testing in myalgic encephalomyelitis/chronic fatigue syndrome patients with or without concomitant fibromyalgia: effects on pressure pain thresholds and temporal summation.

van Campen, C Linda M C, Rowe, Peter C, Verheugt, Freek W A et al.·Clinical and experimental rheumatology·2021

This study tested how standing up quickly (which can trigger ME/CFS symptoms) affects pain sensitivity in ME/CFS patients. Researchers measured how much pressure patients could tolerate on their finger and shoulder before and after a tilt test. They found that ME/CFS patients became more pain-sensitive after the tilt test, meaning their bodies responded to pain more strongly than healthy people, and this effect was even more pronounced in those who also had fibromyalgia.

Autonomic Nervous SystemImmune System

Mitochondria and immunity in chronic fatigue syndrome.

Anderson, G, Maes, M·Progress in neuro-psychopharmacology & biological psychiatry·2020

This review examines how problems with energy-producing structures in cells (mitochondria) and immune system dysfunction may contribute to ME/CFS. The authors propose that two key areas—the gut and immune cells—work together with the body's natural sleep-wake cycle to drive the condition. They also explore how factors like viral infections, gut bacteria, and hormones may play interconnected roles in ME/CFS symptoms.

E3 PreliminaryCohortPEM unclearCross-Sectional

Cerebral Blood Flow Is Reduced in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients During Mild Orthostatic Stress Testing: An Exploratory Study at 20 Degrees of Head-Up Tilt Testing.

van Campen, C Linda M C, Rowe, Peter C, Visser, Frans C·Healthcare (Basel, Switzerland)·2020

This study looked at blood flow to the brain in 19 people with severe ME/CFS who have difficulty standing up (orthostatic intolerance). When patients tilted their heads up at a mild 20-degree angle for 15 minutes, blood flow to their brains dropped by an average of 27%. All 19 patients showed this abnormal reduction in brain blood flow, suggesting this shorter, gentler test could help diagnose the condition even in the most severely ill patients who cannot tolerate longer or more intense tests.

E3 PreliminaryMechanismPEM unclear

A Unifying Hypothesis of the Pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Recognitions from the finding of autoantibodies against ß2-adrenergic receptors.

Wirth, Klaus, Scheibenbogen, Carmen·Autoimmunity reviews·2020

Researchers found that some ME/CFS patients have antibodies (immune proteins) that attack receptors that normally help blood vessels relax and improve blood flow. When these receptors don't work properly, blood vessels may constrict and reduce oxygen delivery to muscles and the brain. This could explain why ME/CFS patients experience fatigue, pain, and cognitive problems.

The Interplay between Oxidative Stress, Exercise, and Pain in Health and Disease: Potential Role of Autonomic Regulation and Epigenetic Mechanisms.

Hendrix, Jolien, Nijs, Jo, Ickmans, Kelly et al.·Antioxidants (Basel, Switzerland)·2020

This review examines how physical activity, pain, and a harmful process called oxidative stress (cellular damage from unstable molecules) interact in both healthy people and those with chronic pain conditions. The authors found that the relationships between these three factors are complicated and depend on the type of exercise and which person is being studied. They suggest that the nervous system's automatic functions and changes in how genes are expressed may help explain why these connections work differently in different people.

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Brain Responses in CFS and TMD to Autonomic Challenges: An Exploratory fMRI Study.

Vuong, Q C, Allison, J R, Finkelmeyer, A et al.·JDR clinical and translational research·2020

This study looked at how the brains of people with ME/CFS respond during a specific breathing test (the Valsalva maneuver) that activates the autonomic nervous system—the part of your nervous system that controls automatic body functions like heart rate and breathing. Researchers compared brain scans of people with ME/CFS who also had jaw pain (temporomandibular disorder) to those with ME/CFS alone and healthy controls. They found that people with both conditions showed stronger brain activity in areas related to pain and fatigue, suggesting that problems with autonomic nervous system control may contribute to both conditions.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Clinical neurophysiology of postural tachycardia syndrome.

Cutsforth-Gregory, Jeremy K, Sandroni, Paola·Handbook of clinical neurology·2019

Postural tachycardia syndrome (POTS) is a condition where your heart rate jumps dramatically when you stand up, causing dizziness, lightheadedness, or other symptoms of not enough blood reaching your brain. It happens five times more often in women than men and can have several different causes, including problems with nerve signals, low blood volume, or deconditioning. Treatment focuses on helping patients stand longer and stay active, using approaches like drinking more fluids, wearing compression socks, and sometimes taking medications.

E3 PreliminaryCohortPEM not requiredCase-Control

Postural orthostatic tachycardia syndrome (POTS): a common but unfamiliar syndrome.

van der Zalm, T, Alsma, J, van de Poll, S W E et al.·The Netherlands journal of medicine·2019

POTS is a condition where standing up quickly causes your heart to beat much faster than normal, and you may feel dizzy, tired, or unwell. This paper describes two different patients with POTS to show how differently the condition can appear from person to person. The authors explain that POTS can overlap with chronic fatigue syndrome and suggest that simple treatments like drinking more water and salt, along with exercise, often help before considering medications.

HPV vaccination syndrome: A clinical mirage, or a new tragic fibromyalgia model.

Martínez-Lavín, Manuel·Reumatologia clinica·2018

Some people have reported developing chronic pain and autonomic symptoms (problems with heart rate, blood pressure, and sweating) after receiving the HPV vaccine. This article reviews whether this connection is real and suggests that if it exists, these cases might share similarities with fibromyalgia—a condition involving widespread pain and nervous system dysfunction. The authors propose that understanding fibromyalgia's mechanisms could help diagnose and treat patients who develop symptoms after HPV vaccination.

E3 PreliminaryReviewPEM not requiredReview-Narrative

Managing fatigue in postural tachycardia syndrome (PoTS): The Newcastle approach.

Strassheim, Victoria, Welford, Jenny, Ballantine, Rob et al.·Autonomic neuroscience : basic & clinical·2018

This review examines fatigue in people with PoTS (postural tachycardia syndrome), a condition where heart rate increases abnormally when standing. The authors explain why fatigue happens in PoTS, how it overlaps with ME/CFS, and describe practical approaches doctors can use to help manage it by treating the individual causes of fatigue in each patient.

E3 PreliminaryMechanismPEM unclearObservational

Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome - a pilot study.

Petrides, George, Zalewski, Pawel, McCulloch, David et al.·Fatigue : biomedicine, health & behavior·2017

This study looked at how the nervous system controls the heart in people with ME/CFS, focusing on a specific part called the sympathetic nervous system. Researchers used specialized imaging to examine nerve connections in the heart and compared them to problems with autonomic function (the automatic nervous system that controls heart rate and blood pressure). The findings suggest that differences in heart nerve connections may be related to why some ME/CFS patients experience autonomic symptoms like dizziness and heart rate changes.

E3 PreliminaryCohortPEM not requiredCase-Control

Sympathetic neural hyperalgesia edema syndrome as a cause of autoimmune hearing loss.

Check, J H·Clinical and experimental obstetrics & gynecology·2017

This case study describes one woman with ME/CFS, pelvic pain, and diarrhea who was given the stimulant medication dextroamphetamine to help with fertility. Unexpectedly, not only did her ME/CFS symptoms improve, but her hearing loss—which had not responded to months of steroid treatment—also significantly improved, as confirmed by hearing tests.

Fibromyalgia syndrome pathology and environmental influences on afflictions with medically unexplained symptoms.

Albrecht, Phillip J, Rice, Frank L·Reviews on environmental health·2016

This review examines fibromyalgia syndrome (FMS) as a model for understanding conditions with symptoms that are difficult to explain medically. The authors discuss how nerve endings in the skin and stress hormones (particularly estrogen) may play a role in causing widespread pain and fatigue. They propose that environmental stress and past trauma can trigger changes in how the nervous system works, leading to increased pain sensitivity.

E3 PreliminaryCohortPEM not requiredCross-Sectional

HPV vaccination syndrome. A questionnaire-based study.

Martínez-Lavín, Manuel, Martínez-Martínez, Laura-Aline, Reyes-Loyola, Paola·Clinical rheumatology·2015

This study looked at people who developed long-lasting pain, fatigue, and heart/blood pressure problems shortly after receiving the HPV vaccine. Researchers used three validated questionnaires to assess 45 people from 13 countries. Most reported muscle pain, tiredness, and dizziness, and after an average of 4 years, 93% still had severe symptoms preventing them from working or going to school.

TMD and chronic pain: a current view.

Furquim, Bruno D'Aurea, Flamengui, Lívia Maria Sales Pinto, Conti, Paulo César Rodrigues·Dental press journal of orthodontics·2015

This review examines how temporomandibular disorders (jaw joint and muscle problems) develop and persist. The authors found that chronic muscle pain in the jaw works similarly to other widespread pain conditions like fibromyalgia and ME/CFS—through a process called central sensitization where the nervous system becomes overly sensitive to pain signals. They explain that genetics and nervous system function influence whether symptoms improve or worsen.