Postural Tachycardia Syndrome (POTS) and the GI Tract: A Primer for the Gastroenterologist

CT-guided Percutaneous Ethanol Sympatholysis for Hyperhidrosis: How I Do It

Hyperhidrosis, excessive sweating from the eccrine sweat glands, is caused by overactivity of the sympathetic nerves. Facial, axillary, and/or palmar hyperhidrosis (excessive sweating of the face, armpits, and hands) has a reported prevalence of 1%-1.6%. This condition is initially treated conservatively using a combination of topical and pharmacologic treatments. Surgical sympathectomy or percutaneous sympatholysis are treatment options for severe hyperhidrosis (grade 3 or 4) that does not respond to conservative management. The aim of intervention is to permanently disrupt the sympathetic signal by targeting the thoracic vertebral levels T2, T3, and T4 of the paravertebral ganglia, located on the anterolateral surface of the vertebral body. This review presents the step-by-step technique for CT-guided percutaneous ethanol sympatholysis and discusses patient selection for the procedure, potential complications, and treatment outcomes. Although more than 90% of patients report complete resolution of hyperhidrosis immediately after sympatholysis, as many as 40% report symptom recurrence within 6 months. The probability of remaining hyperhidrosis-free long term (ie, more than 6 months) after CT-guided sympatholysis is 60%. Procedural risks include a 15% risk of compensatory hyperhidrosis elsewhere in the body, 8% risk of Horner syndrome (mostly self-limiting), 5% risk of pneumothorax, and 3% risk of severe intercostal neuralgia due to nontarget ethanol deposition. Despite the risks, this intervention can be life-altering for those with severe disease.

Adaptive Approaches to Exercise Rehabilitation for Postural Tachycardia Syndrome and Related Autonomic Disorders

Exercise is a well-documented, nonpharmacologic treatment for individuals with autonomic dysfunction and associated orthostatic intolerance, such as postural tachycardia syndrome and related disorders. Exercise has been shown to increase blood volume, reverse cardiovascular deconditioning, and improve quality of life. Current first-line standard of care treatment for autonomic dysfunction combines graded approaches to exercise with medications and lifestyle modifications. However, current exercise rehabilitation protocols for postural orthostatic tachycardia syndrome contain rigid timelines and progression paradigms that often threaten tolerability and adherence. In addition, they fail to account for clinical variables potentially critical to care and lack guidance for individualization, limiting accessibility to patients with co-morbidities that affect exercise appropriateness and safety. Therefore, we introduce an adaptive approach to exercise prescription for orthostatic intolerance that allows patient-specific modifications to meet functional goals for a wider spectrum of patients, thus improving adherence. The proposed approach integrates iterative physiological and symptomatic assessments to provide flexible, yet structured, exposure to aerobic exercise and strength training to improve functional capacity and tolerance of daily activities for patients with postural tachycardia syndrome and related autonomic disorders.

Gastrointestinal manifestations of long COVID

Long COVID is estimated to have affected 6.9 % of US adults, 17.8 million people in the US alone, as of early 2023. While SARS-CoV-2 is primarily considered a respiratory virus, gastrointestinal (GI) symptoms are also frequent in patients with coronavirus disease 2019 (COVID-19) and in patients with Long COVID. The risk of developing GI symptoms is increased with increasing severity of COVID-19, the presence of GI symptoms in the acute infection, and psychological distress both before and after COVID-19. Persistence of the virus in the GI tract, ensuing inflammation, and alteration of the microbiome are all likely mediators of the effects of SARS Co-V-2 virus on the gut. These factors may all increase intestinal permeability and systemic inflammation. GI inflammation and dysbiosis can change the absorption and metabolism of tryptophan, an important neurotransmitter. Long COVID GI symptoms resemble a Disorder of Gut Brain Interaction (DGBI) such as post infection Irritable Bowel Syndrome (IBS). Current standards of treatment for IBS can guide our treatment of Long COVID patients. Dysautonomia, a frequent Long COVID condition affecting the autonomic nervous system, can also affect the GI tract, and must be considered in Long COVID patients with GI symptoms. Long COVID symptoms fall within the broader category of Infection Associated Chronic Conditions (IACCs). Research into the GI symptoms of Long COVID may further our understanding of other post infection chronic GI conditions, and elucidate the roles of therapeutic options including antivirals, probiotics, neuromodulators, and treatments of dysautonomia.

Management of Postural Orthostatic Tachycardia Syndrome in Pediatric Patients: A Clinical Review

Postural orthostatic tachycardia syndrome (POTS) is a chronic illness with unknown mortality and high morbidity, often diagnosed in the adolescent years. Published literature regarding POTS primarily focuses on the adult population, and guidance on treatment in pediatrics is sparse. The purpose of this clinical review is to evaluate the current literature on the management of POTS in pediatric patients. A search was conducted using the Cochrane database, Google Scholar, and PubMed. Studies were included if they evaluated the management of POTS, primarily in pediatric patients. Case reports and series were excluded. Eight published studies met the inclusion and exclusion criteria. To date, there are no US Food and Drug Administration-approved agents for the treatment of POTS. However, select pharmacological therapies have shown positive outcomes by addressing symptom origins, such as providing heart rate control, peripheral autonomic modulation, and targeting hypovolemia. Targeted pharmacological therapies studied in children and young adults include ivabradine, metoprolol, midodrine, pyridostigmine, intravenous crystalloid fluids, and fludrocortisone. Before adding pharmacotherapeutic interventions, non-pharmacologic interventions such as patient education, avoidance of symptom-triggering environments and medications, dietary fluid and sodium supplementation, exercise, and use of compression garments should be first attempted. Although the body of evidence for the management of POTS is expanding, additional research is needed to determine safe and efficacious dosing and establish clear guidelines for POTS in the pediatric population.

An overview of Ehlers Danlos syndrome and the link between postural orthostatic tachycardia syndrome and gastrointestinal symptoms with a focus on gastroparesis

There has been an increasingly reported association between Ehlers-Danlos syndrome (EDS), postural orthostatic tachycardia syndrome (POTS) and gastrointestinal disorders. EDS is a hereditary connective tissue disorder which may manifest as a spectrum of symptoms stemming from collagen defects. The prevalence of EDS is estimated to affect 1 in 5000 individuals which underscores its clinical significance. Notably the hypermobile form (hEDS) accounts for the majority of cases. POTS is characterized by orthostatic intolerance with an increase in heart rate on standing in the absence of hypotension. This condition predominantly affects women between 15 and 45 years of age. Gastrointestinal symptoms in the form of reflux, bloating and abdominal pain significant impact this population. Gastroparesis is a chronic disorder involving symptoms of delayed gastric emptying and may be closely associated with hEDS and POTS, and may be underreported. Autonomic dysfunction associated with hEDS has been proposed as the likely mechanism underlying POTS and gastrointestinal dysfunction though a clear pathophysiological process has not been established.

Central Neuromodulators in Irritable Bowel Syndrome: Why, How, and When

Irritable bowel syndrome (IBS) is responsive to treatments using central neuromodulators. Central neuromodulators work by enhancing the synaptic transmission of 5-hydroxytryptamine, noradrenalin, and dopamine, achieving a slower regulation or desensitization of their postsynaptic receptors. Central neuromodulators act on receptors along the brain-gut axis, so they are useful in treating psychiatric comorbidities, modifying gut motility, improving central downregulation of visceral signals, and enhancing neurogenesis in patients with IBS. Choosing a central neuromodulator for treating IBS should be according to the pharmacological properties and predominant symptoms. The first-line treatment for pain management in IBS is using tricyclic antidepressants. An alternative for pain management is the serotonin and noradrenaline reuptake inhibitors. Selective serotonin reuptake inhibitors are useful when symptoms of anxiety and hypervigilance are dominant but are not helpful for treating abdominal pain. The predominant bowel habit is helpful when choosing a neuromodulator to treat IBS; selective serotonin reuptake inhibitors help constipation, not pain, but may cause diarrhea; tricyclic antidepressants help diarrhea but may cause constipation. A clinical response may occur in 6-8 weeks, but long-term treatment (usually 6-12 months) is required after the initial response to prevent relapse. Augmentation therapy may be beneficial when the therapeutic effect of the first agent is incomplete or associated with side effects. It is recommended to reduce the dose of the first agent and add a second complementary treatment. This may include an atypical antipsychotic or brain-gut behavioral treatment. When tapering central neuromodulators, the dose should be reduced slowly over 4 weeks but may take longer when discontinuation effects occur.

Gastrointestinal symptoms in patients with postural orthostatic tachycardia syndrome in relation to hemodynamic findings and immunological factors

Gastrointestinal (GI) symptoms are common in postural orthostatic tachycardia syndrome (POTS). We aimed to explore the prevalence and severity of GI symptoms in POTS, and to investigate immunological factors, hemodynamic findings, and their possible association with GI symptoms in POTS. Forty-three patients (93% female, median age 30.6 (26.0-41.0) years), previously diagnosed with POTS and 74 healthy controls (78% female, median age 35.6 (28.8-41.7) years) were included. The participants completed a questionnaire including prevalence of GI symptoms, the irritable bowel syndrome severity scoring system (IBS-SSS), and visual analog scale for IBS (VAS-IBS). All POTS patients were previously examined by tilt test (2010-2021) and the vast majority with more recent active standing test (2017-2021), which included monitoring of heart rate (HR). ΔHR was calculated as difference between supine and upright position. Continuous variables from IBS-SSS and VAS-IBS were correlated to ΔHR. A microarray containing several autoantigens commonly targeted in systemic autoimmune disorders was used to assess prevalent autoantibodies in POTS and controls. Total IgE and S-tryptase were analyzed. GI symptoms were more prevalent and severe in POTS than in controls; nausea being the most prevalent (79.1% vs 4.9%, p < 0.001) and bloating and flatulence being the most severe (median 65 (25-88) vs 0 (0-14), p < 0.001). The median total IBS-SSS was 213 (135-319) in POTS vs 13 (0-54) in controls (p < 0.001). Total IBS-SSS was associated with low psychological wellbeing (r = 0.539, p < 0.001) in POTS. ΔHRmax correlated inversely with abdominal pain (r = -0.406, p = 0.007). After adjustments for psychological wellbeing, total IBS-SSS still associated inversely with ΔHR10min (β: 4.748; 95% CI: -9.172 to -0.324; p = 0.036). Similar results were seen with active standing test. The prevalence of autoantibodies did not differ between POTS and controls (29.4% vs 33.3%, p = 0.803). There was no association between GI symptoms and autoantibody status. Total IgE and tryptase were elevated in a few cases. This study confirms the high prevalence of GI symptoms in POTS. More pronounced tachycardia upon tilt table testing seems to be inversely correlated with severity of chronic GI symptoms in POTS. This study did not support the hypothesis that POTS is associated with immunological factors.

Irritable Bowel Syndrome-Like Symptoms in Quiescent Inflammatory Bowel Disease: A Practical Approach to Diagnosis and Treatment of Organic Causes

BACKGROUND

Despite achieving remission in inflammatory bowel disease (IBD), persistent gastrointestinal symptoms are common in quiescent IBD. While irritable bowel syndrome (IBS) is commonly diagnosed in IBD, IBS-like symptoms of recurrent abdominal pain and altered bowel habits can also be attributed to a wide range of overlapping gastrointestinal (GI) etiologies and systemic disorders with GI manifestations that often do not respond to conventional IBS therapies. Delay in diagnosis of these conditions can lead to ongoing patient suffering, reduced quality of life, repetition of invasive testing, increased healthcare utilization, and potentially unnecessary empirical escalation of IBD-related treatments.

AIMS

This review provides a practical approach for the evaluation and diagnosis of IBS mimickers in IBD. We summarize the definition, pathophysiology, diagnosis and treatment of the potential etiologies causing unexplained GI symptoms.

CONCLUSION

Overlapping conditions can co-exist with IBD and explain IBS-like symptoms. The diagnostic work-up in this population should be individualized and tailored to the predominant symptom pattern, associated clinical signs and symptoms and predisposing conditions that can be obtained from a detailed history and physical examination.

Neuropsychiatric Manifestations of Mast Cell Activation Syndrome and Response to Mast-Cell-Directed Treatment: A Case Series

Mast cell activation syndrome (MCAS) is an immune disease with an estimated prevalence of 17%. Mast cell chemical mediators lead to heterogeneous multisystemic inflammatory and allergic manifestations. This syndrome is associated with various neurologic and psychiatric disorders, including headache, dysautonomia, depression, generalized anxiety disorder, and many others. Although MCAS is common, it is rarely recognized, and thus, patients can suffer for decades. The syndrome is caused by aberrant mast cell reactivity due to the mutation of the controller gene. A case series is presented herein including eight patients with significant neuropsychiatric disorders that were often refractory to standard medical therapeutics. Five patients had depression, five had generalized anxiety disorder, and four had panic disorder. Other psychiatric disorders included attention-deficit hyperactivity disorder, obsessive compulsive disorder, phobias, and bipolar disorder. All eight patients were subsequently diagnosed with mast cell activation syndrome; six had comorbid autonomic disorders, the most common being postural orthostatic tachycardia syndrome; and four had hypermobile Ehlers-Danlos syndrome. All patients experienced significant improvements regarding neuropsychiatric and multisystemic symptoms after mast-cell-directed therapy. In neuropsychiatric patients who have systemic symptoms and syndromes, it is important to consider the presence of an underlying or comorbid MCAS.

Clinical characteristics of patients with hypermobile type Ehlers-Danlos syndrome (hEDS) and generalized hypermobility spectrum disorders (G-HSD): an online survey

To examine the perspective of individuals with Hypermobile Ehlers-Danlos Syndrome (hEDS) and Generalized Hypermobility Spectrum Disorder (G-HSD), needed to help identify priorities and improve the lives of people living with these conditions. We conducted an online survey between November 2021 and January 2023. Participants were recruited through the Ehlers-Danlos Society's Research Surveys website. We obtained 483 responses and 396 were analyzed. 80% of the survey's respondents were individuals with hEDS, 90% were females, 30% were between 21 and 30, and 76% lived in North America, with 85% of the participants living in North America indicated being White or European American. Participants reported exercising from none to less than three times per week, with no physical therapy treatment. Ninety-eight percent of participants reported pain mainly at the neck (76%), lower (76%) and upper back (66%), knees (64%), shoulders (60%), and hips (60%). Approximately 80% of participants reported fatigue, joint hypermobility, joint instability, interference with daily activities, gastrointestinal problems, orthostatic hypotension, muscle weakness, and emotional distress. About 60% of respondents indicated walking issues, balance issues, and reduced joint proprioception. Nearly 40% of participants reported pelvic floor dysfunction and cardiovascular problems. Participants with hEDS and G-HSD reported pain on an average (SD) of 6.4 (± 1.3) and 5.9 (± 1.5) days in a typical week, respectively. People with hEDS and G-HSD desperately need more effective treatment options, a better diagnostic process, and education among health care providers.

Sociodemographic Factors, Nutritional Status, and Inflammatory Markers in Patients with Postural Orthostatic Tachycardia Syndrome

Objectives. Postural orthostatic tachycardia syndrome (POTS) is characterized by cardiovascular autonomic dysfunction of unknown etiology with high a prevalence of gastrointestinal symptoms. The aim of the present study was to examine sociodemographic, lifestyle, and nutritional factors as well as inflammatory markers in patients with POTS. Materials and Methods. Forty-three patients with POTS and 61 healthy controls completed questionnaires about sociodemographic factors, lifestyle habits, and gastrointestinal symptoms. Blood samples were analyzed for serum levels of cobalamins, folic acid, iron, total iron-binding capacity (TIBC), ferritin, sodium, potassium, magnesium, phosphorus, albumin, high-sensitive C-reactive protein (CRP), and 25-hydroxyvitamin D (25-OH vitamin D). Results. POTS patients were predominantly women with a lower education level and were more often working part-time, on sick leave, and living alone compared with healthy controls. They reported lower alcohol intake and physical activity levels than controls. The nutrient intake was in general similar in both groups, but POTS patients had a higher intake of different drinks and reported more gastrointestinal symptoms than controls. POTS was associated with higher CRP levels (β: 1.370; 95% CI: 0.004–2.737; $p=0.049$ ), lower albumin levels (β: -1.443; 95% CI: -2.648–(-0.238); $p=0.019$ ), and higher sodium levels (β: 1.392; 95% CI: 0.559–2.225; $p=0.001$ ). Abdominal pain ( $p=0.004$ ) and intestinal symptoms’ influence on daily life ( $p=0.025$ ) were negatively associated with albumin levels. Abdominal pain ( $p=0.011$ ), vomiting and nausea ( $p=0.003$ ), and intestinal symptoms’ influence on daily life ( $p=0.026$ ) were associated with higher sodium levels. Serum levels representing iron and vitamin metabolism were equal between groups. Conclusions. POTS is associated with poorer sociodemographic status, but malnutrition cannot explain POTS or related gastrointestinal symptoms. Higher CRP and lower albumin levels suggest low-grade inflammation as one possible etiological factor.

Mechanisms behind diffuse idiopathic peripheral neuropathy in humans - a systematic review

Introduction: Diffuse peripheral neuropathy is a well-known complication of several conditions, whereas many patients have peripheral neuropathy of unknown etiology and pathophyisology. Increased knowledge of mechanisms may provide insight into enteric neuropathy with gastrointestinal dysmotility. The aim of the present systematic review was to identify mechanisms behind diffuse idiopathic peripheral neuropathies in humans.Methods: Searches were performed in PubMed, Embase, and Web of Science. Human original and review articles, written in English, describing mechanisms behind diffuse peripheral neuropathy verified by objective examinations were intended to be studied. Articles that described animal models, well-described hereditary diseases, drug-induced neuropathy, pain syndromes, malnutrition, and local neuropathy were excluded.Results: In total, 4712 articles were identified. After scrutinizing titles and abstracts, 633 remained and were studied in full text. After the removal of articles not fulfilling inclusion or exclusion criteria, 52 were finally included in this review. The most frequently described neuropathy was diabetic neuropathy, with a wide range of mechanisms involving mitochondrial dysfunction such as oxidative stress and inflammation. Microvascular changes in diabetes and vasculitis lead to ischemia and secondary oxidative stress with inflammation. Structural changes in neurons and glial cells are observed, with abnormalities in different neurotrophic factors. Neuropathy induced by autoantibodies or immunological mechanisms is described in infectious and systemic inflammatory diseases. Several ion channels may be involved in painful neuropathy. No study identified why some patients mainly develop large fiber neuropathy and others small fiber neuropathy.Conclusion: Metabolic and immunological factors and channelopathy may be considered in diffuse idiopathic peripheral neuropathy.

CT-Guided Celiac Ganglion Block for Neurogenic Gastrointestinal Dysmotility

PURPOSE

To determine whether celiac ganglion block can serve as a diagnostic test for dysautonomia as the cause of gastrointestinal dysmotility-related symptoms.

MATERIALS AND METHODS

This was an institutional review board-approved, prospective, single-arm, registered study, from January 2020 to May 2021, and included patients aged 14-85 years with gastrointestinal symptoms of food intolerance, abdominal pain, or angina. Patients with nonneurogenic causes (ie, chronic cholecystitis, peptic ulcer disease, gastroesophageal reflux, and malabsorption syndrome) were excluded. All 15 patients underwent computed tomography-guided celiac ganglion block with 100 mg of liposomal bupivacaine. Patients filled out the dysautonomia-validated questionnaire Composite Autonomic Symptom Score 31 (COMPASS-31) before and after intervention. Differences (before vs after) were compared with the exact permutation method.

RESULTS

Fifteen women (median age, 17 years; range, 14-41 years) were included. Average COMPASS-31 score improved significantly, from baseline 11 (SD ± 2.8) to 4 (SD ± 1.9) (improvement, 7 points ± 2.8; P < .001). All patients reported significant reduction in abdominal angina. Fourteen of the 15 patients (93%) reported complete resolution, and 14 of 15 (93%) reported a significant reduction in non-postprandial abdominal pain (P < .01). Only 1 patient reported no improvement. Eight of those 14 patients (57%) reported complete resolution of abdominal pain. There was a significant improvement in functional scores (vomiting, P = .01; constipation frequency, P = .02; constipation severity, P < .01; and nausea, P < .01). The rate of minor and major adverse events was 13% and 0%, respectively, per the Society of Interventional Radiology adverse event classification.

CONCLUSIONS

Celiac ganglion block is a safe diagnostic tool for confirming dysautonomia as the underlying condition in patients with gastrointestinal dysmotility-related symptoms. It could provide early diagnosis, lead to definitive treatment (ganglionectomy) earlier, or obviate unnecessary surgery.

Review article: diagnostic and therapeutic approach to persistent abdominal pain beyond irritable bowel syndrome

BACKGROUND

Persistent abdominal pain (PAP) poses substantial challenges to patients, physicians and healthcare systems. The possible aetiologies of PAP vary widely across organ systems, which leads to extensive and repetitive diagnostic testing that often fails to provide satisfactory answers. As a result, widely recognised functional disorders of the gut-brain interaction, such as irritable bowel syndrome and functional dyspepsia, are often diagnosed in patients with PAP. However, there are a number of less well-known differential diagnoses that deserve consideration.

AIM

To provide a comprehensive update on causes of PAP that are relatively rare in occurrence.

METHODS

A literature review on the diagnosis and management of some less well-known causes of PAP.

RESULTS

Specific algorithms for the diagnostic work-up of PAP do not exist. Instead, appropriate investigations tailored to patient medical history and physical examination findings should be made on a case-by-case basis. After a definitive diagnosis has been reached, some causes of PAP can be effectively treated using established approaches. Other causes are more complex and may benefit from a multidisciplinary approach involving gastroenterologists, pain specialists, psychologists and physiotherapists. This list is inclusive but not exhaustive of all the rare or less well-known diseases potentially associated with PAP.

CONCLUSIONS

Persistent abdominal pain (PAP) is a challenging condition to diagnose and treat. Many patients undergo repeated diagnostic testing and treatment, including surgery, without achieving symptom relief. Increasing physician awareness of the various causes of PAP, especially of rare diseases that are less well known, may improve patient outcomes.

Neurological disorders and small bowel dysmotility

PURPOSE OF REVIEW

Small bowel dysmotility is common in the context of neurological disorders. Overlooking it can have an adverse impact on patient's quality of life and neurological outcomes. This review focuses on describing the mechanisms and effects of enteric dysmotility in neurological patients and providing treatment options.

RECENT FINDINGS

Small bowel dysmotility is prevalent among neurological patients. The definition and diagnosis of small bowel dysmotility is a challenge; however, up to two-thirds of neurological patients may experience associated symptoms. Small bowel dysmotility can affect the absorption of nutrients and medication, impacts on social and professional function and can result in malnutrition and its associated morbidity and mortality.

SUMMARY

Small bowel dysmotility due to a neuropathy can result from acute or chronic disorders in the central and peripheral nervous system and includes the cerebral cortex, brain stem, spinal cord, parasympathetic (vagus) and sympathetic nerves and the myenteric and submucosal plexuses of the intestine. Generalized muscle disorders can also cause an enteral myopathy. Generally, the disorders may be degenerative or inflammatory. Both enteric neuropathy and myopathy may cause symptoms of abdominal pain, nausea/vomiting, bloating, constipation or diarrhoea and can cause malnutrition. The symptoms need to be addressed in order of importance to the patient and malnutrition prevented or treated.

Regional Gastrointestinal Transit and Contractility Patterns Vary in Postural Orthostatic Tachycardia Syndrome (POTS)

BACKGROUND

Postural orthostatic tachycardia syndrome (POTS) is an autonomic disorder that affects multiple organs, including the gastrointestinal system. These patients often have multiple GI complaints with a severe impact on their quality of life. GI dysmotility patterns in POTS remains poorly understood and difficult to manage.

AIMS

The aim of this study was to investigate the diagnostic yield of wireless motility capsule in patients with gastrointestinal symptoms and POTS, with use of a symptomatic control group without POTS as a reference.

METHODS

We retrospectively reviewed the charts of patients who had both autonomic testing and wireless motility capsule between 2016 and 2020. The two groups were divided into those with POTS and those without POTS (controls) as diagnosed through autonomic testing. We compared the regional transit times and motility patterns between the two groups using the data collected from wireless motility capsule.

RESULTS

A total of 25% of POTS patients had delayed small bowel transit compared to 0% of non-POTS patients (p = 0.047). POTS patients exhibited hypo-contractility patterns within the small bowel, including decreased contractions/min (2.95 vs. 4.22, p = 0.011) and decreased motility index (101.36 vs. 182.11, p = 0.021). In multivariable linear regression analysis, migraine predicted faster small bowel transit (p = 0.007) and presence of POTS predicted slower small bowel transit (p = 0.044).

CONCLUSIONS

Motility abnormalities among POTS patients seem to affect mostly the small bowel and exhibit a general hypo-contractility pattern. Wireless motility capsule can be a helpful tool in patients with POTS and GI symptoms as it can potentially help guide treatment.

Scleroderma and the Esophagus

The gastrointestinal tract is the second largest organ system in the body and is often affected by connective tissue disorders. Scleroderma is the classic rheumatologic disease affecting the esophagus; more than 90% of patients with scleroderma have esophageal involvement. This article highlights esophageal manifestations of scleroderma, focusing on pathogenesis, clinical presentation, diagnostic considerations, and treatment options. In addition, this article briefly reviews the esophageal manifestations of other key connective tissue disorders, including mixed connective tissue disease, myositis, Sjogren syndrome, systemic lupus erythematosus, fibromyalgia, and Ehlers-Danlos syndrome.

Symptomatic use of carbidopa in autonomic disorders

Carbidopa is being explored as a novel therapy for hyperadrenergic symptoms of autonomic disorders, due to its potential to decrease peripheral catecholamine levels. This study retrospectively characterized patients in our autonomic clinic who were prescribed carbidopa for open label treatment of autonomic symptoms. 23 patients were included; approximately half had postural orthostatic tachycardia syndrome. Those with documented plasma catecholamines had elevated standing norepinephrine. Patients typically had multiple comorbidities and multiple failed therapies. 19 took carbidopa (typically 25 mg three times daily); 12 continued it for longer than 3 months. 11 patients reported better symptom control with carbidopa, most commonly tremor and gastrointestinal dysfunction. 4 patients reported side effects. In this small retrospective study, carbidopa was well tolerated in patients with dysautonomia, and half reported symptomatic benefit. Larger, placebo-controlled trials are warranted for further investigation of this therapy.

Nutritional Implications of Patients with Dysautonomia and Hypermobility Syndromes

PURPOSE OF REVIEW

Dysautonomia and hypermobility syndrome are two distinct but often overlapping clinical conditions that are recognized for their complex multiorgan system afflictions. The purpose of this review is to investigate dietary strategies to reduce symptoms and augment quality of life in this growing patient population.

RECENT FINDINGS

There is increasing evidence supporting dietary modifications to include food rich in probiotics and prebiotics, along with fiber supplements to reduce gastrointestinal symptoms. Adequate salt and fluid intake may reduce orthostatic hypotension symptoms. Dietary supplements may help with osteoarticular, musculoskeletal, and fatigue symptoms. Individualized diet strategies and supplements can reduce the multiorgan system symptoms observed in dysautonomia and hypermobility syndrome.

Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1

Postural orthostatic tachycardia syndrome (POTS) is a chronic and often disabling disorder characterized by orthostatic intolerance with excessive heart rate increase without hypotension during upright posture. Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance and gastrointestinal distress. A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence. The onset of POTS may be precipitated by immunological stressors such as a viral infection. A variety of pathophysiologies are involved in the abnormal postural tachycardia response; however, the pathophysiology of the syndrome is incompletely understood and undoubtedly multifaceted. Clinicians and researchers focused on POTS convened at the National Institutes of Health in July 2019 to discuss the current state of understanding of the pathophysiology of POTS and to identify priorities for POTS research. This article, the first of two articles summarizing the information discussed at this meeting, summarizes the current understanding of this disorder and best practices for clinical care. The evaluation of a patient with suspected POTS should seek to establish the diagnosis, identify co-morbid conditions, and exclude conditions that could cause or mimic the syndrome. Once diagnosed, management typically begins with patient education and non-pharmacologic treatment options. Various medications are often used to address specific symptoms, but there are currently no FDA-approved medications for the treatment of POTS, and evidence for many of the medications used to treat POTS is not robust.

Mast Cell Activation Syndrome: A Primer for the Gastroenterologist

Mast cell activation syndrome is thought to be a common, yet under-recognized, chronic multi-system disorder caused by inappropriate mast cell activation. Gastrointestinal symptoms are frequently reported by these patients and are often mistaken by physicians as functional gastrointestinal disorders. This syndrome can be diagnosed by the medical history and measurable biomarkers. Gastroenterologists manage diseases associated with active inflammatory cells including neutrophils, lymphocytes, macrophages, and eosinophils. The mast cell has only recently been recognized as a major player in our specialty. Gastrointestinal disorders from mast cell mediators often present with apparent irritable bowel syndrome, dyspepsia, chronic or cyclical nausea, and heartburn. Individuals with mast cell activation syndrome experience significant delays in diagnosis. The gastrointestinal symptoms are often refractory to symptom-targeted prescription medications. Beyond avoiding triggers, the best therapy is directed at modulating mast cell activation and the effects of the mediators. Many of these therapies are simple over-the-counter medications. In this article, we review mast cell function and dysfunction and the gastrointestinal symptoms, comorbid conditions, diagnosis, and management of mast cell activation syndrome. Gastroenterologists who become aware of this syndrome can dramatically improve the quality of life for their patients who previously have been labeled with a functional gastrointestinal disorder.

Assessment of Gastrointestinal Autonomic Dysfunction: Present and Future Perspectives

The autonomic nervous system delicately regulates the function of several target organs, including the gastrointestinal tract. Thus, nerve lesions or other nerve pathologies may cause autonomic dysfunction (AD). Some of the most common causes of AD are diabetes mellitus and α-synucleinopathies such as Parkinson’s disease. Widespread dysmotility throughout the gastrointestinal tract is a common finding in AD, but no commercially available method exists for direct verification of enteric dysfunction. Thus, assessing segmental enteric physiological function is recommended to aid diagnostics and guide treatment. Several established assessment methods exist, but disadvantages such as lack of standardization, exposure to radiation, advanced data interpretation, or high cost, limit their utility. Emerging methods, including high-resolution colonic manometry, 3D-transit, advanced imaging methods, analysis of gut biopsies, and microbiota, may all assist in the evaluation of gastroenteropathy related to AD. This review provides an overview of established and emerging assessment methods of physiological function within the gut and assessment methods of autonomic neuropathy outside the gut, especially in regards to clinical performance, strengths, and limitations for each method.

Cutaneous alpha-synuclein deposition in postural tachycardia patients

Objective

To report a case series of patients with neuropathic POTS and cutaneous phosphorylated alpha‐synuclein (P‐SYN) deposition on skin biopsy and compare these to neuropathic POTS patients without P‐SYN deposition.

Methods

The medical history, physical examination findings, autonomic function testing, and skin biopsy neuropathology of patients under the age of 50 with a postural tachycardia and a diagnosis of POTS were retrospectively reviewed. Included patients completed the composite autonomic severity score (COMPASS 31), the Wood Mental Fatigue Inventory, the Epworth Sleepiness scale, the REM Behavior Disorder Questionnaire, the Patient‐Reported Outcomes Measurement Information System (PROMIS‐10), and the Gastroparesis Cardinal Symptom Index.

Results

Of 296 patients seen with POTS, 22 patients with suspected neuropathic POTS had skin biopsies performed during their evaluation. Seven of 22 patients had P‐SYN present on skin biopsy, while 15 individuals did not. Those with P‐SYN on biopsy: (1) were more likely to be male; (2) had features of REM sleep behavioral disorder; (3) reported less sleepiness and cognitive impairment; and (4) noted greater symptoms of gastroparesis. On autonomic testing, the group with P‐SYN deposition was more likely to have a hypertensive response to tilt‐table testing and abnormal QSART responses.

Interpretation

Phosphorylated alpha‐synuclein deposition is present in some postural tachycardia patients with neuropathic features. Individuals with a postural tachycardia and cutaneous phosphorylated alpha‐synuclein deposition may be distinguished from other patients with neuropathic POTS.

Gastrointestinal motility disorders in neurologic disease

The extrinsic and autonomic nervous system intricately controls the major functions of the gastrointestinal tract through the enteric nervous system; these include motor, secretory, sensory, storage, and excretory functions. Disorders of the nervous system affecting gastrointestinal tract function manifest primarily as abnormalities in motor (rather than secretory) functions. Common gastrointestinal symptoms in neurologic disorders include sialorrhea, dysphagia, gastroparesis, intestinal pseudo-obstruction, constipation, diarrhea, and fecal incontinence. Diseases of the entire neural axis ranging from the cerebral hemispheres to the peripheral autonomic nerves can result in gastrointestinal motility disorders. The most common neurologic diseases affecting gastrointestinal function are stroke, parkinsonism, multiple sclerosis, and diabetic neuropathy. Diagnosis involves identification of the neurologic disease and its distribution, and documentation of segmental gut dysfunction, typically using noninvasive imaging, transit measurements, or intraluminal measurements of pressure activity and coordination of motility. Apart from treatment of the underlying neurologic disease, management focuses on restoration of normal hydration and nutrition and pharmacologic treatment of the gut neuromuscular disorder.

Rome IV Functional Gastrointestinal Disorders and Health Impairment in Subjects With Hypermobility Spectrum Disorders or Hypermobile Ehlers-Danlos Syndrome

BACKGROUND & AIMS

Individuals with hypermobility spectrum disorder or hypermobile Ehlers-Danlos Syndrome (HSD/hEDS) are increasingly encountered by gastroenterologists and pose complex clinical challenges. Uncontrolled studies have found functional gastrointestinal disorders (FGIDs) to be common in patients with HSD/hEDS. Some patients have somatic symptoms (medically unexplained symptoms) that might affect FGIDs. We performed a case-control study to determine the prevalence of and factors associated with Rome IV FGIDs in subjects with HSD/hEDS compared with age- and sex- matched population-based controls.

METHODS

An online general health survey was completed by 603 individuals with HSD/hEDS in October 2018 (cases) and 603 matched individuals from the population of the United Kingdom (controls) in 2015. The mean participant age was 39 yrs, and 96% were women. The survey included questions about Rome IV FGIDs, non-GI and non-musculoskeletal somatic symptoms (maximum number, 10), quality of life, medical history and healthcare use. The prevalence of FGIDs was compared between cases and controls, with subsequent logistic regression models - adjusting for the number of somatic symptoms - used to determine the associations for FGIDs in HSD/hEDS compared with controls.

RESULTS

Nearly all subjects (98%) with HSD/hEDS fulfilled symptom-based criteria for 1 or more Rome IV FGIDs, compared with 47% of controls (P < .0001). The gastrointestinal regions most commonly affected by FGIDs in individuals with HSD/hEDS and control subjects were the bowel (90% vs 40% of controls), gastroduodenal (70% vs 13% of controls), esophageal (56% vs 6% of controls), and anorectal (53% vs 9% of controls); P < .0001. A higher proportion of subjects with HSD/hEDS had FGIDs in 2 or more regions (84% vs 15% of controls; P < .0001). Subjects with HSD/hEDS also reported a significantly higher number of non-GI and non-musculoskeletal somatic symptoms (7.1 vs 3.3 in controls), lower quality of life, and greater healthcare use, including abdominal surgeries and medication use (for example, 84% used analgesics compared with 29% of controls). Almost 40% of subjects with HSD/hEDS reported a diagnosis of chronic fatigue syndrome and/or fibromyalgia. Following adjustments for somatic symptoms, the association for FGIDs in subjects with HSD/hEDS was reduced by as much as 4-fold and in some instances was eliminated.

CONCLUSIONS

In a large case-control study of persons with HSD/hEDS, almost all of the cases met criteria for Rome IV FGIDs, incurred considerable health impairment, and had high healthcare use. Patients with HSD/hEDS frequently have somatic symptoms that should be treated to reduce the high burden of gastrointestinal illness in this population.

Functional gastrointestinal disorders are increased in joint hypermobility-related disorders with concomitant postural orthostatic tachycardia syndrome

BACKGROUND

Individuals with hypermobility spectrum disorders/hypermobile Ehlers-Danlos syndrome (HSD/hEDS) frequently fulfill criteria for Rome IV functional gastrointestinal disorders (FGIDs). Postural orthostatic tachycardia syndrome (POTS) is also commonly reported in HSD/hEDS and may impact on co-morbidity with and severity of FGIDs, although this remains to be studied. We determined the impact of concomitant POTS and HSD/hEDS on their association with Rome IV FGIDs.

METHODS

With the help of the charity organization Ehlers-Danlos Support UK, an online cross-sectional health survey was completed by individuals with HSD/hEDS. The survey enquired for (a) self-reported doctor diagnosis of POTS, chronic fatigue syndrome, and fibromyalgia, (b) the presence and symptom frequency of Rome IV FGIDs, and (c) anxiety and depression scores.

KEY RESULTS

Of 616 subjects with HSD/hEDS, 37.5% reported a doctor diagnosis of POTS. POTS-positive individuals were significantly younger than POTS-negative subjects (37 vs 40 years, P = 0.002), more likely to report chronic fatigue syndrome (44% vs 31%, P < 0.0001), and showed a trend toward increased prevalence of fibromyalgia (44% vs 37%, P = 0.06) and higher depression score (P = 0.07). POTS-positive subjects were also more likely to fulfill criteria for Rome IV FGIDs across various organ domains and experienced both upper and lower gastrointestinal symptoms significantly more frequently. The increased associations for FGIDs and GI symptom frequency remained unchanged in HSD/hEDS subjects with POTS following adjustments for age, chronic fatigue syndrome, fibromyalgia, and depression scores.

CONCLUSIONS AND INFERENCES

The high FGID burden in HSD/hEDS is further amplified in the presence of POTS. Future studies should elucidate the mechanism by which POTS arises in HSD/hEDS and is associated with increased GI symptoms.

Mechanisms and management of gastrointestinal symptoms in postural orthostatic tachycardia syndrome

Postural orthostatic tachycardia syndrome (POTS) is a disorder of orthostatic intolerance associated with many GI manifestations that can be broadly classified into two different categories: those present all the time (non-positional) and those that occur with orthostatic position change. There are also many conditions that can co-exist with POTS such as mast cell activation syndrome and the hypermobile form of Ehlers-Danlos syndrome (hEDS) that are also oftentimes associated with GI symptoms. In the current issue of Neurogastroenterology and Motility, Tai et al. explored the relationship between functional GI disorders among hEDS patients with and without concomitant POTS and showed that the hEDS-POTS cohort was more likely to have more than one GI organ involved compared to the cohort with hEDS alone, and certain GI symptoms were also more common in the hEDS-POTS cohort. In this review article, we will briefly review the literature surrounding putative mechanisms responsible for GI symptoms in POTS with an emphasis on the contributory role of concomitant hEDS and then discuss management strategies for GI symptoms in POTS.

Postural Tachycardia Syndrome: Nutrition Implications

Postural tachycardia syndrome (POTS) is a syndrome characterized by elevated heart rate without hypotension and most commonly occurs in young females (generally <35 years of age). The prevalence of POTS is on the rise, but the etiology is still under investigation, and there appear to be multiple potential physiologic causes. The majority of these patients experience a multitude of gastrointestinal (GI) and systemic symptoms and conditions that may contribute to functional debility and poor quality of life. Although symptoms generally improve with age, they can still lead to significant issues meeting nutrition and hydration needs. This paper summarizes the understood potential pathophysiology of POTS, associated GI and nutrition issues, general treatment of POTS, and strategies to assess and meet the unique nutrition and hydration needs of these patients.

Postural orthostatic tachycardia syndrome: clinical presentation, aetiology and management

Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder characterized by an excessive heart rate increase on standing and orthostatic intolerance. POTS affects younger individuals 15-45 years old with a distinct female predominance (≈80%). The prevalence ranges between 0.2% and 1.0% in developed countries. The onset of POTS is typically precipitated by immunological stressors such as viral infection, vaccination, trauma, pregnancy, surgery or psychosocial stress. The most common complaints are dizziness, weakness, rapid heartbeat and palpitation on standing. Moreover, patients often report physical deconditioning and reduced exercise capacity as well as headache, 'brain fog', dyspnoea, gastrointestinal disorders and musculoskeletal pain. The aetiology of POTS is largely unknown and three main hypotheses include an autoimmune disorder, abnormally increased sympathetic activity and catecholamine excess, and sympathetic denervation leading to central hypovolaemia and reflex tachycardia. The golden standard for POTS diagnosis is head-up tilt test with a non-invasive beat-to-beat haemodynamic monitoring. Although long-term prognosis of POTS is poorly explored, around 50% of patients spontaneously recover within 1-3 years. After the diagnosis has been established, patient should be thoroughly educated about non-pharmacological measures alleviating the symptoms. Exercise training may be very effective and counteract deconditioning. In more symptomatic patients, different drugs directed at controlling heart rate, increasing peripheral vasoconstriction and intravascular volume can be tested. However, the overall effects of pharmacological therapy are modest and the most affected patients remain handicapped. Future efforts should focus on better understanding of POTS pathophysiology and designing randomized controlled trials for selection of more effective therapy.