Fibromyalgia syndrome—am I an autoimmune condition?

Abstract:

Assessments of serum-autoantibodies in fibromyalgia syndrome (FMS) date back to the 1980s and have yielded inconsistent results. Based on a new passive transfer paradigm, since 2021 causative involvement of immunoglobulin G–mediated autoimmunity in severe FMS has been demonstrated in several studies, which have included UK, Swedish, and Canadian patients. These findings open the path to the development of novel diagnostic and immune-therapeutic approaches.

Autoantibody targets and downstream mechanisms and the molecular processes that translate infection-, toxicity-, or stress-triggers into the FMS immune response in genetically or otherwise vulnerable individuals require study. These results in FMS also suggest that other chronic pain conditions or nonpainful symptom-based disorders may similarly be caused by noninflammatory minimally destructive autoantibody-mediated autoimmunity, thus offering hope for large groups of patients.

Source: Goebel A. Fibromyalgia syndrome-am I an autoimmune condition? Pain Rep. 2025 Jul 2;10(4):e1270. doi: 10.1097/PR9.0000000000001270. PMID: 40612406; PMCID: PMC12226001. https://pmc.ncbi.nlm.nih.gov/articles/PMC12226001/ (Full text)

Inflammation, Autoimmunity, and Infection in Fibromyalgia: A Narrative Review

Abstract:

Fibromyalgia (FM) is a chronic disease characterized by widespread musculoskeletal pain of unknown etiology. The condition is commonly associated with other symptoms, including fatigue, sleep disturbances, cognitive impairment, and depression. For this reason, FM is also referred to as FM syndrome. The nature of the pain is defined as nociplastic according to the latest international classification and is characterized by altered nervous sensitization both centrally and peripherally. Psychosocial conditions have traditionally been considered critical in the genesis of FM. However, recent studies in animal models and humans have provided new evidence in favor of an inflammatory and/or autoimmune pathogenesis.

In support of this hypothesis are epidemiological data of an increased female prevalence, similar to that of autoimmune diseases, and the frequent association with immune-mediated inflammatory disorders. In addition, the observation of an increased incidence of this condition during long COVID revived the hypothesis of an infectious pathogenesis. This narrative review will, therefore, discuss the evidence supporting the immune-mediated pathogenesis of FM in light of the most current data available in the literature.

Source: Paroli M, Gioia C, Accapezzato D, Caccavale R. Inflammation, Autoimmunity, and Infection in Fibromyalgia: A Narrative Review. Int J Mol Sci. 2024 May 29;25(11):5922. doi: 10.3390/ijms25115922. PMID: 38892110; PMCID: PMC11172859. https://pmc.ncbi.nlm.nih.gov/articles/PMC11172859/ (Full text)

Is fibromyalgia an autoimmune disorder?

Highlights:

  • Certain aspects of FM are still controversial, including pathophysiology, which remain a subject of debate
  • FM shares many clinical features, sometimes designing overlapping diseases, with other conditions, including, chronic fatigue syndrome (CFS), sick building syndrome (SBS), post-COVID syndrome, and many others
  • Anti-GPCR (anti- G protein-coupled receptor antibodies), autoantibodies directed against the autonomic nervous system receptors, have been detected in the serum of patients with FM, and their titers correlated with clinical symptoms
  • Fibromyalgia belongs to nociplastic pain which means that the central nervous system is the driving force behind this pain mechanism, and the key phenotypic features include widespread pain, fatigue, and sleep, memory, and mood disturbances

Abstract:

Fibromyalgia (FM) is a multifactorial syndrome which includes not only widespread pain and stiffness, now recognized as major symptoms, but also numerous other somatic, emotional, and neuropsychic manifestation. The lack of specific validated biological and instrumental biomarkers has made FM a condition of unexplained medical significance, and its pathophysiology remains controversial and subject to debate. The current hypothesis regarding the pathogenesis of FM proposes that its development is influenced by various mechanism, including genetic predisposition, stressful life events, inflammatory processes, and cognitive-emotional factors. However, despite the extensive research conducted to date, the available data do not provide a clear understanding of the pathogenesis of FM.
In this article, we report the opposing viewpoints of two leading experts who debate the question of whether FM is an autoimmune disease, based on scientific data regarding this condition. Both perspectives are discussed and the latest evidence on the pathophysiology of FM is reported to provide a comprehensive understanding of this complex syndrome.
Source: Clauw D, Sarzi-Puttini P, Pellegrino G, Shoenfeld Y. Is fibromyalgia an autoimmune disorder? Autoimmun Rev. 2024 Jan;23(1):103424. doi: 10.1016/j.autrev.2023.103424. Epub 2023 Aug 25. PMID: 37634681. https://www.sciencedirect.com/science/article/pii/S1568997223001581 (Full text)

Patient experiences of remote consulting with chronic fatigue syndrome/myalgic encephalomyelitis and fibromyalgia: a qualitative study

Abstract:

Background: Remote and digital consulting in primary care has rapidly expanded since March 2020. It is important to understand patient experiences, particularly for those living with complex long-term conditions, to identify how care can best be delivered, including within the remote space.

Aim: To explore the experiences of people living with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and fibromyalgia when consulting remotely in primary care.

Design & setting: Semi-structured interviews with patients living with CFS/ME and fibromyalgia in general practice in England.

Method: Semi-structured interviews were carried out with 13 participants. The interviews were transcribed and analysed thematically according to a Foucauldian theoretical framework.

Results: All participants highlighted needing to feel believed by clinicians. Many reported difficulties with telephone and online consulting owing to the lack of physical communication. Positive outcomes were reported when there was a good relationship with a clinician. Continuity in care and recognising the complexity of these conditions were also considered important.

Conclusion: This study allowed people living with CFS/ME and fibromyalgia to describe their experiences when consulting remotely. Participants highlighted needing to feel listened to and felt they benefited from an ongoing relationship with a clinician although this was difficult to achieve when consulting remotely. Some advantages of remote consulting were reported, particularly when symptoms were troublesome. Flexible access systems, with a range of consultation modalities or preferred clinician(s) availability, could improve healthcare encounters, particularly given the increased use of remote consulting in primary care.

Source: Leach H, Eccles A, Chew-Graham CA, Atherton H. Patient experiences of remote consulting with chronic fatigue syndrome/myalgic encephalomyelitis and fibromyalgia: a qualitative study. BJGP Open. 2025 Apr 24;9(1):BJGPO.2024.0079. doi: 10.3399/BJGPO.2024.0079. PMID: 39191480; PMCID: PMC12137999. https://pmc.ncbi.nlm.nih.gov/articles/PMC12137999/ (Full text)

The pivotal role of central sensitization in long COVID, fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Introduction: Long COVID is a condition characterized by persistent unexplained symptoms following COVID-19 infection. These symptoms are not related to another disease or organ damage and are similar to those in fibromyalgia and myslgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

Areas covered: The similar clinical and pathophysiological features and management of long COVID, fibromyalgia and ME/CFS are explored from the unifying framework of central sensitivity syndromes. The article is based on a literature search utilizing PubMed for content published between 2021 and 1 May 2025, using search terms: long COVID, long COVID syndrome, post-COVID-19, post-acute SARS-CoV-2, fibromyalgia, ME/CFS, post-exertional malaise and central sensitization.

Expert opinion: Once long COVID is redefined to exclude patients with well-defined organ disease, it fits best as a model of central sensitization. Long COVID is a single syndrome, rather than many distinct diseases. Optimal management of long COVID and similar central sensitivity

Source: Goldenberg DL. The pivotal role of central sensitization in long COVID, fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome. Expert Rev Neurother. 2025 Jun 13:1-17. doi: 10.1080/14737175.2025.2516097. Epub ahead of print. PMID: 40512228. https://www.tandfonline.com/doi/full/10.1080/14737175.2025.2516097

Ignored, dismissed, and minimized: Understanding the harmful consequences of invalidation in health care-A systematic meta-synthesis of qualitative research

Abstract:

The upsurge in the prevalence of contested, ambiguous, and difficult-to-diagnose illnesses presents challenges for clinicians who too often respond by invalidating patients’ symptoms. Although numerous qualitative studies have reported the effects of invalidation on patients’ psychological and behavioral outcomes, this body of research has not been systematically reviewed. Informed by Linehan’s (1993) conceptualization of invalidation, this systematic review elucidated the negative consequences, of symptom invalidation, or the dismissal or minimization of a person’s experiences with illness.

We reviewed 151 qualitative reports representing 11,307 individuals with Ehlers-Danlos syndrome, endometriosis, fibromyalgia syndrome, Gulf War syndrome, irritable bowel syndrome, long COVID, multiple chemical sensitivity, myalgic encephalomyelitis/chronic fatigue syndrome, postural orthostatic tachycardia syndrome, systemic lupus erythematosus, and vulvodynia.

Consistent with Linehan’s theorizing, thematic analysis identified four broad classes of consequences: induced emotional states and beliefs (e.g., shame, suicidality), induced health care emotional states and beliefs (e.g., health care-related anxiety and trauma), induced health care behavior (e.g., health care system avoidance), and diagnostic delay.

Informed by these findings, we developed a novel conceptual model explaining how symptom invalidation leads to these consequences and thereby undermines health outcomes. Future work should explore the proposed conceptual model and identify theoretically informed interventions and policies aimed at preventing symptom invalidation to improve psychological, behavioral, and health outcomes. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Source: Bontempo AC, Bontempo JM, Duberstein PR. Ignored, dismissed, and minimized: Understanding the harmful consequences of invalidation in health care-A systematic meta-synthesis of qualitative research. Psychol Bull. 2025 Apr;151(4):399-427. doi: 10.1037/bul0000473. PMID: 40310228. https://psycnet.apa.org/fulltext/2026-10154-001.html (Full text)

Impact of the COVID-19 Pandemic and the 2021 National Institute for Health and Care Excellence Guidelines on Public Perspectives Toward Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Thematic and Sentiment Analysis on Twitter (Rebranded as X)

Abstract:

Background: Myalgic encephalomyelitis (ME), also referred to as chronic fatigue syndrome (CFS), is a complex illness that typically presents with disabling fatigue and cognitive and functional impairment. The etiology and management of ME/CFS remain contentious and patients often describe their experiences through social media.

Objective: We explored public discourse on Twitter (rebranded as X) to understand the concerns and priorities of individuals living with ME/CFS, with a focus on (1) the COVID-19 pandemic and (2) publication of the 2021 UK National Institute for Health and Care Excellence (NICE) guidelines on the diagnosis and management of ME/CFS.

Methods: We used the Twitter application programming interface to collect tweets related to ME/CFS posted between January 1, 2010, and January 30, 2024. Tweets were sorted into 3 chronological periods (pre-COVID-19 pandemic, post-COVID-19 pandemic, and post-UK 2021 NICE Guidelines publication). A Robustly Optimized Bidirectional Embedding Representations from Transformers Pretraining Approach (RoBERTa) language processing model was used to categorize the sentiment of tweets as positive, negative, or neutral. We identified tweets that mentioned COVID-19, the UK NICE guidelines, and key themes identified through latent Dirichlet allocation (ie, fibromyalgia, research, and treatment). We sampled 1000 random tweets from each theme to identify subthemes and representative quotes.

Results: We retrieved 906,404 tweets, of which 427,824 (47.2%) were neutral, 369,371 (40.75%) were negative, and 109,209 (12.05%) were positive. Over time, both the proportion of negative and positive tweets increased, and the proportion of neutral tweets decreased (P<.001 for all changes). Tweets mentioning fibromyalgia acknowledged similarities with ME/CFS, stigmatization associated with both disorders, and lack of effective treatments. Treatment-related tweets often described frustration with ME/CFS labeled as mental illness, dismissal of concerns by health care providers, and the need to seek out “good physicians” who viewed ME/CFS as a physical disorder. Tweets on research typically praised studies of biomarkers and biomedical therapies, called for greater investment in biomedical research, and expressed frustration with studies suggesting a biopsychosocial etiology for ME/CFS or supporting management with psychotherapy or graduated activity. Tweets about the UK NICE guidelines expressed frustration with the 2007 version that recommended cognitive behavioral therapy and graded exercise therapy, and a prolonged campaign by advocacy organizations to influence subsequent versions. Tweets showed high acceptance of the 2021 UK NICE guidelines, which were seen to validate ME/CFS as a biomedical disease and recommended against graded exercise therapy. Tweets about COVID-19 often noted overlaps between post-COVID-19 condition and ME/CFS, including claims of a common biological pathway, and advised there was no cure for either condition.

Conclusions: Our findings suggest research is needed to inform how best to support patients’ engagement with evidence-based care. Furthermore, while patient involvement with ME/CFS research is critical, unmanaged intellectual conflicts of interest may threaten the trustworthiness of research efforts.

Source: Khakban I, Jain S, Gallab J, Dharmaraj B, Zhou F, Lokker C, Abdelkader W, Zeraatkar D, Busse JW. Impact of the COVID-19 Pandemic and the 2021 National Institute for Health and Care Excellence Guidelines on Public Perspectives Toward Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Thematic and Sentiment Analysis on Twitter (Rebranded as X). J Med Internet Res. 2025 May 21;27:e65087. doi: 10.2196/65087. PMID: 40397934. https://www.jmir.org/2025/1/e65087 (Full text)

The gut microbiota promotes pain in fibromyalgia

Highlights:

• Transplanting gut microbiota from women with fibromyalgia into mice induces pain
• It also induces immune activation, metabolomic changes, and reduced skin innervation
• Gut microbiota promotes pain through several mechanisms
Summary:

Fibromyalgia is a prevalent syndrome characterized by widespread pain in the absence of evident tissue injury or pathology, making it one of the most mysterious chronic pain conditions. The composition of the gut microbiota in individuals with fibromyalgia differs from that of healthy controls, but its functional role in the syndrome is unknown. Here, we show that fecal microbiota transplantation from fibromyalgia patients, but not from healthy controls, into germ-free mice induces pain and numerous molecular phenotypes that parallel known changes in fibromyalgia patients, including immune activation and metabolomic profile alterations. Replacing the fibromyalgia microbiota with a healthy microbiota substantially alleviated pain in mice. An open-label trial in women with fibromyalgia (Registry MOH_2021-11-04_010374) showed that transplantation of a healthy microbiota is associated with reduced pain and improved quality of life. We conclude that altered gut microbiota has a role in fibromyalgia pain, highlighting it as a promising target for therapeutic interventions.
Source: Cai W, Haddad M, Haddad R, Kesten I, Hoffman T, Laan R, Westfall S, Defaye M, Abdullah NS, Wong C, Brown N, Tansley S, Lister KC, Hooshmandi M, Wang F, Lorenzo LE, Hovhannisyan V, Ho-Tieng D, Kumar V, Sharif B, Thurairajah B, Fan J, Sahar T, Clayton C, Wu N, Zhang J, Bar-Yoseph H, Pitashny M, Krock E, Mogil JS, Prager-Khoutorsky M, Séguéla P, Altier C, King IL, De Koninck Y, Brereton NJB, Gonzalez E, Shir Y, Minerbi A, Khoutorsky A. The gut microbiota promotes pain in fibromyalgia. Neuron. 2025 Apr 18:S0896-6273(25)00252-1. doi: 10.1016/j.neuron.2025.03.032. Epub ahead of print. PMID: 40280127. https://www.cell.com/neuron/fulltext/S0896-6273(25)00252-1 (Full text)

HERV activation segregates ME/CFS from fibromyalgia while defining a novel nosologic entity

Abstract:

Research of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia (FM), two acquired chronic illnesses affecting mainly females, has failed to ascertain their frequent co-appearance and etiology. Despite prior detection of human endogenous retrovirus (HERV) activation in these diseases, the potential biomarker value of HERV expression profiles for their diagnosis, and the relationship of HERV expression profiles with patient immune systems and symptoms had remained unexplored.

By using HERV-V3 high-density microarrays (including over 350k HERV elements and more than 1500 immune-related genes) to interrogate the transcriptomes of peripheral blood mononuclear cells from female patients diagnosed with ME/CFS, FM, or both, and matched healthy controls (n = 43), this study fills this gap of knowledge. Hierarchical clustering of HERV expression profiles strikingly allowed perfect participant assignment into four distinct groups: ME/CFS, FM, co-diagnosed, or healthy, pointing at a potent biomarker value of HERV expression profiles to differentiate between these hard-to-diagnose chronic syndromes.

Differentially expressed HERV-immune-gene modules revealed unique profiles for each of the four study groups and highlighting decreased γδ T cells, and increased plasma and resting CD4 memory T cells, correlating with patient symptom severity in ME/CFS. Moreover, activation of HERV sequences coincided with enrichment of binding sequences targeted by transcription factors which recruit SETDB1 and TRIM28, two known epigenetic silencers of HERV, in ME/CFS, offering a mechanistic explanation for the findings.

Unexpectedly, HERV expression profiles appeared minimally affected in co-diagnosed patients denoting a new nosological entity with low epigenetic impact, a seemingly relevant aspect for the diagnosis and treatment of this prevalent group of patients.

Source: Giménez-Orenga K, Martín-Martínez E, Nathanson L, Oltra E. HERV activation segregates ME/CFS from fibromyalgia while defining a novel nosologic entity. Elife. 2025 May 8;14:RP104441. doi: 10.7554/eLife.104441. PMID: 40338225. https://elifesciences.org/articles/104441 (Full text)

Dysregulation of lipid metabolism, energy production, and oxidative stress in myalgic encephalomyelitis/chronic fatigue syndrome, Gulf War Syndrome and fibromyalgia

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), Gulf War Syndrome (GWS), and Fibromyalgia (FM) are complex, chronic illnesses with overlapping clinical features. Symptoms that are reported across these conditions include post-exertional malaise (PEM), fatigue, and pain, yet the etiology of these illnesses remains largely unknown. Diagnosis is challenging in patients with these conditions as definitive biomarkers are lacking; patients are required to meet clinical criteria and often undergo lengthy testing to exclude other conditions, a process that is often prolonged, costly, and burdensome for patients.

The identification of reliable validated biomarkers could facilitate earlier and more accurate diagnosis and drive the development of targeted pharmacological therapies that might address the underlying pathophysiology of these diseases. Major driving forces for biomarker identification are the advancing fields of metabolomics and proteomics that allow for comprehensive characterization of metabolites and proteins in biological specimens. Recent technological developments in these areas enable high-throughput analysis of thousands of metabolites and proteins from a variety of biological samples and model systems, that provides a powerful approach to unraveling the metabolic phenotypes associated with these complex diseases.

Emerging evidence suggests that ME/CFS, GWS, and FM are all characterized by disturbances in metabolic pathways, particularly those related to energy production, lipid metabolism, and oxidative stress. Altered levels of key metabolites in these pathways have been reported in studies highlighting potential common biochemical abnormalities. The precise mechanisms driving altered metabolic pathways in ME/CFS, GWS, and FM remain to be elucidated; however, the elevated oxidative stress observed across these illnesses may contribute to symptoms and offer a potential target for therapeutic intervention.

Investigating the mechanisms, and their role in the disease process, could provide insights into disease pathogenesis and reveal novel treatment targets. As such, comprehensive metabolomic and proteomic analyses are crucial for advancing the understanding of these conditions in-order to identify both common, and unique, metabolic alterations that could serve as diagnostic markers or therapeutic targets.

Source: Davis L, Higgs M, Snaith A, Lodge TA, Strong J, Espejo-Oltra JA, Kujawski S, Zalewski P, Pretorius E, Hoerger M, Morten KJ. Dysregulation of lipid metabolism, energy production, and oxidative stress in myalgic encephalomyelitis/chronic fatigue syndrome, Gulf War Syndrome and fibromyalgia. Front Neurosci. 2025 Mar 10;19:1498981. doi: 10.3389/fnins.2025.1498981. PMID: 40129725; PMCID: PMC11931034. https://pmc.ncbi.nlm.nih.gov/articles/PMC11931034/ (Full text)