Altered immunity in migraine: a comprehensive scoping review

BACKGROUND

The pathogenesis of migraine remains unclear; however, a large body of evidence supports the hypothesis that immunological mechanisms play a key role. Therefore, we aimed to review current studies on altered immunity in individuals with migraine during and outside attacks.

METHODS

We searched the PubMed database to investigate immunological changes in patients with migraine. We then added other relevant articles on altered immunity in migraine to our search.

RESULTS

Database screening identified 1,102 articles, of which 41 were selected. We added another 104 relevant articles. We found studies reporting elevated interictal levels of some proinflammatory cytokines, including IL-6 and TNF-α. Anti-inflammatory cytokines showed various findings, such as increased TGF-β and decreased IL-10. Other changes in humoral immunity included increased levels of chemokines, adhesion molecules, and matrix metalloproteinases; activation of the complement system; and increased IgM and IgA. Changes in cellular immunity included an increase in T helper cells, decreased cytotoxic T cells, decreased regulatory T cells, and an increase in a subset of natural killer cells. A significant comorbidity of autoimmune and allergic diseases with migraine was observed.

CONCLUSIONS

Our review summarizes the findings regarding altered humoral and cellular immunological findings in human migraine. We highlight the possible involvement of immunological mechanisms in the pathogenesis of migraine. However, further studies are needed to expand our knowledge of the exact role of immunological mechanisms in migraine pathogenesis.

Autoimmunity in Syndromes of Orthostatic Intolerance: An Updated Review

Orthostatic intolerance is a broad term that represents a spectrum of dysautonomic disorders, including postural orthostatic tachycardia syndrome (POTS) and orthostatic hypotension (OH), as manifestations of severe autonomic failure. While the etiology of orthostatic intolerance has not yet fully been uncovered, it has been associated with multiple underlying pathological processes, including peripheral neuropathy, altered renin-aldosterone levels, hypovolemia, and autoimmune processes. Studies have implicated adrenergic, cholinergic, and angiotensin II type I autoantibodies in the pathogenesis of orthostatic intolerance. Several case series have demonstrated that immunomodulation therapy resulted in favorable outcomes, improving autonomic symptoms in POTS and OH. In this review, we highlight the contemporary literature detailing the association of autoimmunity with POTS and OH.

A review of cytokine-based pathophysiology of Long COVID symptoms

The Long COVID/Post Acute Sequelae of COVID-19 (PASC) group includes patients with initial mild-to-moderate symptoms during the acute phase of the illness, in whom recovery is prolonged, or new symptoms are developed over months. Here, we propose a description of the pathophysiology of the Long COVID presentation based on inflammatory cytokine cascades and the p38 MAP kinase signaling pathways that regulate cytokine production. In this model, the SARS-CoV-2 viral infection is hypothesized to trigger a dysregulated peripheral immune system activation with subsequent cytokine release. Chronic low-grade inflammation leads to dysregulated brain microglia with an exaggerated release of central cytokines, producing neuroinflammation. Immunothrombosis linked to chronic inflammation with microclot formation leads to decreased tissue perfusion and ischemia. Intermittent fatigue, Post Exertional Malaise (PEM), CNS symptoms with "brain fog," arthralgias, paresthesias, dysautonomia, and GI and ophthalmic problems can consequently arise as result of the elevated peripheral and central cytokines. There are abundant similarities between symptoms in Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). DNA polymorphisms and viral-induced epigenetic changes to cytokine gene expression may lead to chronic inflammation in Long COVID patients, predisposing some to develop autoimmunity, which may be the gateway to ME/CFS.

POTS and Pregnancy: A Review of Literature and Recommendations for Evaluation and Treatment

Postural Orthostatic Tachycardia Syndrome (POTS) is a disorder of the autonomic nervous system most commonly affecting women of reproductive age. Studies on POTS and pregnancy are limited, and there is a lack of clinical guidelines regarding assessment and management of pregnant women with POTS. The purpose of this review is to summarize data from the available studies on the topic of pregnancy in POTS and common comorbid conditions and to provide the clinical recommendations regarding evaluation and treatment of POTS in pregnant women, based on the available studies and clinical experience. We conclude that pregnancy appears to be safe for women with POTS and is best managed by a multi-disciplinary team with knowledge of POTS and its various comorbidities. Importantly, large, prospective studies are needed to better delineate the course and outcomes of pregnancy, as well as possible pregnancy-related complications in women with POTS. Clinicians should be aware of the clinical presentation, diagnostic criteria, and treatment options in pregnant women with POTS to optimize outcomes and improve medical care during pregnancy and post-partum period.

Postural tachycardia syndrome (POTS) and antiphospholipid syndrome (APS): What do we know so far?

As part of the non-criteria clinical manifestations, postural orthostatic tachycardia syndrome (POTS), a multisystem autonomic dysfunction, can co-exist with antiphospholipid syndrome (APS). Several pieces of evidence hint on the autoimmune basis of POTS, and its possible association with several autoimmune diseases, including APS. Indeed, the evidence exists in the etiologies, symptomatology, and treatment options. Although infections, viral ones in particular, stress, and pregnancy are etiologies to both POTS and APS, the exact pathophysiological connection is still to be studied taking into consideration the activity of cytokines in both diseases. Nevertheless, certain immunomodulatory treatments used for the catastrophic or obstetrical forms of APS, such as intravenous immunoglobulins (IVIG) and steroids, have been also used for the treatment of POTS resistant to classical treatments. Therefore, our review aims to highlight the association between POTS and APS, shedding light on the common etiologies explaining the pathophysiology of the two disorders, the diagnostic approach to POTS as a possible clinical criterion of APS, and the treatment of APS in the context of treating POTS.

Covid-19-Induced Dysautonomia: A Menace of Sympathetic Storm

Among the plethora of debilitating neurological disorders of COVID-19 syndrome in survivors, the scope of SARS-CoV-2-induced dysautonomia (DNS) is yet to be understood, though the implications are enormous. Herein, we present an inclusive mini-review of SARS-CoV-2-induced DNS and its associated complications. Although, the direct link between Covid-19 and DSN is still speculative, the hypothetical links are thought to be either a direct neuronal injury of the autonomic pathway or a para/post-infectious immune-induced mechanism. SARS-CoV-2 infection-induced stress may activate the sympathetic nervous system (SNS) leading to neuro-hormonal stimulation and activation of pro-inflammatory cytokines with further development of sympathetic storm. Sympathetic over-activation in Covid-19 is correlated with increase in capillary pulmonary leakage, alveolar damage, and development of acute respiratory distress syndrome. Furthermore, SARS-CoV-2 can spread through pulmonary mechanoreceptors and chemoreceptors to medullary respiratory center in a retrograde manner resulting in sudden respiratory failure. Taken together, DSN in Covid-19 is developed due to sympathetic storm and inhibition of Parasympathetic nervous system-mediated anti-inflammatory effect with development of cytokine storm. Therefore, sympathetic and cytokine storms together with activation of Renin-Angiotensin-System are the chief final pathway involved in the development of DSN in Covid-19.

Headache and immunological/autoimmune disorders: a comprehensive review of available epidemiological evidence with insights on potential underlying mechanisms

Several lines of evidence support a role of the immune system in headache pathogenesis, with particular regard to migraine. Firstly, alterations in cytokine profile and in lymphocyte subsets have been reported in headache patients. Secondly, several genetic and environmental pathogenic factors seem to be frequently shared by headache and immunological/autoimmune diseases. Accordingly, immunological alterations in primary headaches, in particular in migraine, have been suggested to predispose some patients to the development of immunological and autoimmune diseases. On the other hand, pathogenic mechanisms underlying autoimmune disorders, in some cases, seem to favour the onset of headache. Therefore, an association between headache and immunological/autoimmune disorders has been thoroughly investigated in the last years. The knowledge of this possible association may have relevant implications in the clinical practice when deciding diagnostic and therapeutic approaches. The present review summarizes findings to date regarding the plausible relationship between headache and immunological/autoimmune disorders, starting from a description of immunological alteration of primary headaches, and moving onward to the evidence supporting a potential link between headache and each specific autoimmune/immunological disease.

Post COVID-19 Syndrome in Patients with Asymptomatic/Mild Form

Post COVID-19 Syndrome (PCS) is a complex of various symptoms developing a month or more after the acute phase of the disease. The cases of PCS development among patients with asymptomatic/mild forms are frequently reported; however, the pathogenesis of PCS in this group of patients is still not completely clear. The publications about COVID-19 which were published in online databases from December 2019 to September 2021 are analyzed in this review. According to the analysis, PCS develops on average in 30-60% of patients, mainly among women. Fatigue, shortness of breath, cough, and anosmia were reported as the most common symptoms. The possible association between the described PCS symptoms and brain damage was revealed. We assume the possibility of an alternative course of COVID-19, which develops in genetically predisposed individuals with a stronger immune response, in which it predominantly affects the cells of the nervous system, possibly with the presence of an autoimmune component, which might have similarity with chronic fatigue syndrome or autoimmune disautonomia. Thus, the gender (female) and the presence of anosmia during an asymptomatic or mild course of the disease can be predictive factors for the development of PCS, which can be caused by autoimmune damage to neurons, glia, and cerebral vessels.

POTS and Antiphospholipid Syndrome: An Unlikely Association

Antiphospholipid syndrome is a rare complication of postural orthostatic tachycardia syndrome. Clinically, the presentation has overlapping symptoms of both diseases, with lightheadedness or syncope when moving from a supine to a standing position as well as blood clots, headache, or pregnancy complications in women. This case presentation involves a 39-year-old patient identified as female who has been diagnosed with POTS and elevated anticardiolipin antibodies.

Cardiovascular Disease in Antiphospholipid Syndrome

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Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by venous, arterial or microvascular thrombosis or obstetric events in the presence of persistently positive antiphospholipid antibodies and constitutes a major cause of cardiovascular events in young people. Τhis review highlights the pathophysiology of cardiovascular complications in patients with APS and possible treatment options.

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Patients with APS have endothelial dysfunction, accelerated endothelial proliferation and intimal hyperplasia, atherogenesis, platelet activation, inflammatory products secretion and coagulation-fibrinolytic dysregulation. Cardiovascular complications include accelerated atherosclerosis, acute coronary syndrome, Libman-Sacks endocarditis, cardiomyopathy and venous, arterial or intracardiac thrombi. Moreover, pulmonary hypertension and peripheral microvascular dysfunction are common findings.

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Management of these patients is not well documented. The role of primary thrombosis prevention remains controversial in individuals with positive antiphospholipid antibodies. Treatment of traditional cardiovascular risk factors according to current guidelines for the prevention of cardiovascular disease in the general population is recommended for primary prevention of APS. Anticoagulation therapy with unfractionated or low-molecular-weight heparin overlapped with a vitamin K antagonist remains the mainstay of the treatment for APS patients with venous thrombosis, whereas direct oral anticoagulants are not yet recommended. Data are scarce regarding the secondary arterial thrombosis prevention and it is not clear whether dual or triple antithrombotic therapy is necessary. To date, it is recommended to follow current guidelines for the management of acute coronary syndrome in the general population. New treatment targets are promising options for patients with catastrophic APS.

Deep capillary retinal ischemia and high-titer prothrombin-associated antiphospholipid antibodies: A case series of three patients

Purpose

Acute macular neuroretinopathy has been shown to be due to ischemia of the deep capillary retinal plexus and most cases occur in young women; we hypothesized that there may be an association with antiphospholipid antibodies.

Observations

We identified three patients who were diagnosed with deep capillary retinal ischemia after presenting with sudden onset of focal paracentral scotoma who tested persistently positive for antiphospholipid antibodies. All patients had high-titer prothrombin-associated antibodies and two of the three also had low-titer anticardiolipin antibodies. In all patients, the diagnosis was missed at the initial presentation. All patients experienced involvement of both eyes over time with permanent visual deficits and all were female with an average age at symptom onset of 34 years. All patients were using exogenous estrogen and had additional but previously undiagnosed symptoms or signs that may be seen in the antiphospholipid syndrome. One patient was ANA positive with a titer of 1:320, but none had lupus-specific antibodies or clinical features of lupus.

Conclusions and Importance

The persistent presence of high-titer prothrombin-associated antiphospholipid antibodies in three women with deep capillary retinal ischemia suggests this may be an important association. Prothrombin-associated antibodies (anti-prothrombin IgG and anti-phosphatidylserine-prothrombin IgG and IgM) as well as the traditional antiphospholipid antibodies (anticardiolipin IgG, IgM and IgA; anti-beta 2 glycoprotein I IgG, IgM and IgA; and the lupus anticoagulant) should be included in the diagnostic work-up of patients diagnosed with deep capillary retinal ischemia. Because of the broader health and treatment implications of high-titer antiphospholipid antibodies, further investigation into this suspected association is warranted.

Fibromyalgia and small fiber neuropathy: the plot thickens!

Several groups of investigators have described the presence of small fiber neuropathy in fibromyalgia patients. This writing discusses how this new finding could renovate fibromyalgia concept, diagnosis, and treatment. Predominant rheumatology thinking proposes fibromyalgia as a "centralized pain syndrome." An alternative hypothesis views fibromyalgia as a stress-related dysautonomia with neuropathic pain features. Dorsal root ganglia may be the key autonomic-nociceptive short-circuit sites. The recent recognition of small fiber neuropathy in a large subgroup of fibromyalgia patients reinforces the dysautonomia-neuropathic hypothesis and validates fibromyalgia pain. These new findings support fibromyalgia as a primarily neurological entity, nevertheless, rheumatologist will likely remain the best equipped specialist to diagnose fibromyalgia and differentiate it from other multi-symptomatic rheumatic syndromes. Skin biopsy and corneal confocal microscopy will probably become useful fibromyalgia diagnostic tests. Dorsal root ganglia sodium channel blockers are potential fibromyalgia analgesic medications. Subgroups of young girls with "autoimmune neuropathic fibromyalgia" may respond to immunoglobulin therapy. Multimodal intervention directed to regain autonomic nervous system resilience will likely remain the cornerstone for fibromyalgia therapy.

Evaluation of postural tachycardia syndrome (POTS)

The diagnostic evaluation of a patient with suspected postural tachycardia syndrome (POTS) requires a thoughtful diagnostic approach utilizing a careful clinical history and examination, laboratory, and autonomic testing. This article outlines the importance of a thorough history in identifying mechanism of symptom onset, clinical features, associated clinical conditions or disorders, and factors that may result in symptom exacerbation. The clinical examination involves an assessment of pupillary responses, an evaluation for sudomotor and vasomotor signs, and an assessment for joint hypermobility. Laboratory testing helps to exclude mimics of autonomic dysfunction, recognize conditions that may exacerbate symptoms, and to identify conditions that may cause or be associated with autonomic nervous system disease. The purpose of autonomic testing is to confirm a POTS diagnosis, exclude other causes of orthostatic intolerance, and may provide for characterization of POTS into neuropathic and hyperadrenergic subtypes. Other diagnostic studies, such as epidermal skin punch biopsy, exercise testing, radiographic studies, sleep studies, gastrointestinal motility studies, and urodynamic studies should be considered when clinically appropriate.

Autonomic neuropathy-in its many guises-as the initial manifestation of the antiphospholipid syndrome

Autonomic disorders have previously been described in association with the antiphospholipid syndrome. The present study aimed to determine the clinical phenotype of patients in whom autonomic dysfunction was the initial manifestation of the antiphospholipid syndrome and to evaluate for autonomic neuropathy in these patients. This was a retrospective study of 22 patients evaluated at the University of Colorado who were found to have a disorder of the autonomic nervous system as the initial manifestation of antiphospholipid syndrome. All patients had persistent antiphospholipid antibody positivity and all patients who underwent skin biopsy were found to have reduced sweat gland nerve fiber density suggestive of an autonomic neuropathy. All patients underwent an extensive evaluation to rule out other causes for their autonomic dysfunction. Patients presented with multiple different autonomic disorders, including postural tachycardia syndrome, gastrointestinal dysmotility, and complex regional pain syndrome. Despite most having low-titer IgM antiphospholipid antibodies, 13 of the 22 patients (59%) suffered one or more thrombotic event, but pregnancy morbidity was minimal. Prothrombin-associated antibodies were helpful in confirming the diagnosis of antiphospholipid syndrome. We conclude that autonomic neuropathy may occur in association with antiphospholipid antibodies and may be the initial manifestation of the syndrome. Increased awareness of this association is important, because it is associated with a significant thrombotic risk and a high degree of disability. In addition, anecdotal experience has suggested that antithrombotic therapy and intravenous immunoglobulin therapy may result in significant clinical improvement in these patients.

Postural tachycardia syndrome: current perspectives

Postural tachycardia syndrome (POTS) is the combination of an exaggerated heart rate response to standing, in association with symptoms of lightheadedness or pre-syncope that improve when recumbent. The condition is often associated with fatigue and brain fog, resulting in significant disruptions at a critical time of diagnosis in adolescence and young adulthood. The heterogeneity of the underlying pathophysiology and the variable response to therapeutic interventions make management of this condition challenging for both patients and physicians alike. Here, we aim to review the factors and mechanisms that may contribute to the symptoms and signs of POTS and to present our perspectives on the clinical approach toward the diagnosis and management of this complex syndrome.

Coexistence of antiphospholipid antibodies and cephalalgia

Background

The occurrence of antiphospholipid antibodies (aPLs) and headache comorbidity in the presence or absence of underlying autoimmune diseases remains unclear.

Aim

The aim of this review was to summarize the relationship between headache and aPLs based on evidences from cohort studies and case reports, in addition to examining the treatment strategies that resolved headache in aPLs-positive individuals.

Methods

A comprehensive literature search was conducted through PubMed, ISI Web of Science and Google Scholar. A total of 559 articles were screened and the appropriate articles were selected based on quality and level of evidence.

Results

Cohort studies (n = 27) from Europe, North America and Asia demonstrated comorbidity of aPLs and headache in antiphospholipid syndrome, systemic lupus erythematosus (SLE) and neuropsychiatric SLE patients. Significantly higher association between migraine and aPLs was observed (n = 170/779; p < 0.0001) in individuals without any underlying diseases. Our analysis of shortlisted case reports (n = 17) showed that a higher frequency of anticardiolipin antibodies were present in subjects with different autoimmune disorders (70.6%). Corticosteroids were highly effective in resolving headache in aPLs-positive individuals.

Conclusion

Higher frequency of comorbidity between aPLs and headache was observed in healthy individuals and patient cases. Therefore, experimental studies are warranted to evaluate the aPLs-induced pathogenic mechanism of headache.

Intravenous Hydration for Management of Medication-Resistant Orthostatic Intolerance in the Adolescent and Young Adult

Orthostatic intolerance (OI) is common in teenagers (T) and young adults (A). Despite treatment with oral fluids, medication, and exercise, a significant number have symptoms from multiple organ systems and suffer low quality of life (QOL). Previous studies showed that acute intravenous (IV) hydration (IH) could help restore orthostatic tolerance; however, no data are available about the intermediate-term effects of IH. We therefore studied the efficacy of IH to improve QOL and manage medication-refractory OI patients. Our study population consisted of 39 patients (mean age = 16.1 ± 3.3) years; thirty-two were female. Average number of medications failed = 3.1. Average QOL score on self-reported OI questionnaire was 4.2 (normal QOL = 10). IV hydration consisted of normal saline (1-2 l/day, 3-7 days/week). 1) Orthostatic testing revealed Postural Orthostatic Tachycardia (24), Neurally Mediated Hypotension (14) or OI (1). 2) Average orthostatic change in heart rate was 48 ± 18 bpm. 3) IH was performed via intermittent IV access (10), PICC line (22), and Port (7). 4) Duration of IH varied from 1 week to 3.8 years (mean = 29 ± 47 weeks). 5) Overall, 79 % (n = 31) demonstrated clinically improved self-reported QOL. 6) Six patients who discontinued IH requested to restart treatment. (7) Complications consisted of upper extremity deep vein thrombosis (n = 3) and infection (n = 4). IH is an effective therapy to improve QOL in T&A with medication-resistant OI. Most patients continued to report improved QOL once IH was discontinued. IH should be considered a therapeutic option in medication-resistant OI patients with low QOL.

Autoimmune markers and autoimmune disorders in patients with postural tachycardia syndrome (POTS)

OBJECTIVE

In recent years, there have been a number of studies suggesting that POTS may have an autoimmune etiology. This study examined whether the prevalence of antinuclear antibodies (ANA), other markers of autoimmunity and co-morbid autoimmune disorders is higher in patients with POTS than in the general population.

METHODS AND RESULTS

Medical records of 100 consecutive patients with POTS evaluated at our clinic were reviewed. In this cohort (90% females, mean age 32, range 13-54 years), 25% had positive ANA, 7% had at least one positive aPL antibody and 31% had markers of autoimmunity. When compared to the general population, patients with POTS had a higher prevalence of ANA (25% vs. 16%, OR 1.8, CI 1.1-2.8, p < 0.05), aPL antibody (7% vs. 1%, OR 7.5, CI 3.4-16.1, p < 0.001) and co-morbid autoimmune disorders (20% vs. highest estimated 9.4%, OR 2.4, CI 1.5-3.9, p < 0.001). The most prevalent autoimmune disorder was Hashimoto's thyroiditis (11% vs. up to 2%, OR 6.1, CI 3.2-11.3, p < 0.001), followed by RA (4% vs. up to 1%, OR 4.1, CI 1.5-11.2, p < 0.01) and SLE (2% vs. up to 0.12%, OR 17, CI 4.1-69.7, p < 0.001). The prevalence of CVID was very high (2% vs. 0.004%, OR 510.2, CI 92.4-2817.8, p < 0.001), while celiac disease showed a nonsignificant trend toward increased prevalence.

CONCLUSION

Patients with POTS have a higher prevalence of autoimmune markers and co-morbid autoimmune disorders than the general population. One in four patients have positive ANA, almost one in three have some type of autoimmune marker, one in five have a co-morbid autoimmune disorder, and one in nine have Hashimoto's thyroiditis.

Orthostatic intolerance and postural tachycardia syndrome as suspected adverse effects of vaccination against human papilloma virus

BACKGROUND

Infections with human papilloma virus (HPV) can result in cervical, oropharyngeal, anal, and penile cancer and vaccination programs have been launched in many countries as a preventive measure. We report the characteristics of a number of patients with a syndrome of orthostatic intolerance, headache, fatigue, cognitive dysfunction, and neuropathic pain starting in close relation to HPV vaccination.

METHODS

Patients were referred for orthostatic intolerance following HPV vaccination. Symptoms of autonomic dysfunction were quantified by standardised questionnaire. The diagnosis of postural orthostatic tachycardia syndrome (POTS) rested on finding a sustained heart rate increment of >30 min(-1) (>40 min(-1) in adolescents) or to levels >120 min(-1) during orthostatic challenge.

RESULTS

35 women aged 23.3 ± 7.1 years participated. Twenty-five had a high level of physical activity before vaccination and irregular periods were reported by all patients not on treatment with oral contraception. Serum bilirubin was below the lower detection limit in 17 patients. Twenty-one of the referred patients fulfilled the criteria for a diagnosis of POTS (60%, 95%CI 43-77%). All patients had orthostatic intolerance, 94% nausea, 82% chronic headache, 82% fatigue, 77% cognitive dysfunction, 72% segmental dystonia, 68% neuropathic pain.

CONCLUSIONS

In a population referred for symptoms of orthostatic intolerance and other symptoms consistent with autonomic dysfunction that began in close temporal association with a quadrivalent HPV vaccination, we identified a 60% prevalence of POTS. Further work is urgently needed to elucidate the potential for a causal link between the vaccine and circulatory abnormalities and to establish targeted treatment options for the affected patients.