Gastric electrical activity becomes abnormal in the upright position in patients with postural tachycardia syndrome

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.

Pediatric Postural Orthostatic Tachycardia Syndrome: Where We Stand

Postural orthostatic tachycardia syndrome (POTS), first described in 1992, remains an enigmatic, yet severely and variably debilitating, disorder. The pathophysiology of this syndrome is still not understood, and there remains no biomarker indicating the presence of POTS. Although research interest has increased in recent years, there are relatively fewer clinical and research studies addressing POTS in children and adolescents compared with adults. Yet, adolescence is when a large number of cases of POTS begin, even among adult patients who are subsequently studied. This article summarizes reported research in POTS, specifically in pediatric patients, including discussion of aspects of diagnostic criteria, risk factors and outcomes, neurohormonal and hemodynamic abnormalities, clinical assessment, and treatment. The goals of this review are increased recognition and acknowledgment of POTS among pediatric and adolescent providers, as well as to provide an understanding of reported abnormalities of homeostasis, such that symptomatic patients will be able to be recognized and appropriately managed, enabling them to return to their activities of daily living.

Impact of Comorbidities on the Prognosis of Pediatric Postural Tachycardia Syndrome

OBJECTIVE

To investigate the influence of comorbidities on the prognosis of pediatric postural tachycardia syndrome (POTS).

METHODS

In this retrospective cohort study, 275 children with POTS admitted to the Department of Pediatrics at Peking University First Hospital were recruited from 2016 to 2019 and followed up. The participants were divided into simple POTS (S-POTS, n=156 cases) and POTS with comorbidities (Co-POTS, n=119 cases) groups according to whether they were complicated with comorbidities. A Cox regression analysis was used to identify the prognostic risk factors for children with POTS, while Kaplan-Meier curves were applied to compare the cumulative symptom remission rate (CSRR) between the two groups. The rehospitalization of the children between the two groups was also compared to explore the influence of comorbidities.

RESULTS

Twenty-one participants (7.6%) were lost during a median follow-up of 24 months. The Cox regression model showed that comorbidities and body mass index (BMI) were associated with the CSRR of the children with POTS. The CSRR of pediatric POTS alone was 1.748 times higher than that of patients with comorbidities, and the CSRR was decreased by 5.1% for each 1 kg/m2 increase in BMI. The most common comorbidity in children with POTS in this study was allergic disorders, followed by the psychological diseases. The patients in the Co-POTS group had a lower CSRR than those in the S-POTS group (log rank P=0.0001). In addition, compared with those of the S-POTS group, the total number of rehospitalizations was high (P=0.001), and the total hospital stays were long in the Co-POTS group (P<0.001).

CONCLUSION

Complicating with comorbidities, pediatric patients with POTS had lower CSRR and more rehospitalizations than those without comorbidities. More attention should be given to comorbidities when managing pediatric POTS.

Using the PEOP Model to Understand Barriers to Functioning in Postural Orthostatic Tachycardia Syndrome

Individuals with postural orthostatic tachycardia syndrome (POTS) experience many barriers that lead to decreased functioning and quality of life. At this time, there are limited resources regarding the functional impact of POTS on occupational performance. Therefore, this narrative review demonstrates how occupational therapy practitioners can conceptualize, categorize, and systematically organize their thinking around barriers individuals with POTS experience using the Person-Environment-Occupation-Performance (PEOP) model of practice.

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.

Effects of Varying Acupuncture Manipulations at ST36 (Zusanli) on Gastric Electrical Frequency and Amplitude in Bradygastria Rabbits

Objective

To observe the effects of different manual acupuncture (MA) manipulation on gastric electrical amplitude and frequency for noradrenaline-induced bradygastria in rabbits.

Methods

A total of 60 rabbits were randomly allocated into six groups: four MA manipulation groups; reinforcing by twisting the manipulation group (FTG), reducing by twisting the manipulation group (RTG), reinforcing by lifting and thrusting the manipulation group (FLG), and reducing by lifting and thrusting the manipulation group (RLG), a control group (CG), and a model group (MG). The total treatment time length was 45 minutes. The bradygastria was induced via administration of noradrenaline via the marginal ear vein of the rabbits at 5 minutes from baseline, and the bradygastria model was established at 12 minutes from baseline. The rabbits in the four MA manipulation groups received different stimulation parameters at ST36 (Zusanli) for a duration of 3 minutes in accordance with their respective group allocation. The needles were then retained without further manipulation for a further 25 minutes. Gastric electrical amplitude and frequency were recorded using a data acquisition system (Biopac System MP150) at five different time points: baseline (for a duration of 5 minutes), after the bradygastria model was established at 12 minutes from baseline (for a duration of 5 minutes), during MA manipulation commencing at 17 minutes from baseline (for a duration of 3 minutes), 5 minutes after MA manipulation at 25 minutes from baseline (for a duration of 5 minutes), and at 20 minutes following MA manipulation at 40 minutes from baseline (for a duration of 5 minutes).

Results

After noradrenaline induction, gastric electrical frequency levels in MA and MG groups were significantly decreased compared to the CG group (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (P < 0.05). However, there were no significant changes to gastric electrical amplitude (

Conclusion

All four variations of MA manipulations have a recovery effect on the gastric electrical frequency of rabbits with bradygastria. In particular, results indicated that FTG, RTG, and FLG at ST36 may have a regular and significant recovery trend through the whole process of the acupuncture intervention.

Utility of Diagnostic Studies for Upper Gastrointestinal Symptoms in Children with Orthostatic Intolerance

OBJECTIVE

To assess the utility of gastrointestinal (GI) diagnostic studies in the evaluation of patients with orthostatic intolerance.

STUDY DESIGN

Medical records of 103 consecutive children/young adults with orthostatic intolerance and gastrointestinal symptoms were reviewed. All patients had undergone antroduodenal manometry in conjunction with the tilt table test, autonomic testing, and upper gastrointestinal endoscopy (EGD). A gastric emptying study (GES) was performed in 81 patients.

RESULTS

The median age of the cohort was 17 years (IQR, 15-19) with a female predominance (females:males, 3:1). As expected, the tilt table test was abnormal in all patients. Antroduodenal manometry was abnormal in 83 of 103 patients (81%), showing neurogenic intestinal dysmotility in 50%, rumination in 20%, and visceral hyperalgesia in 10%. The GES results were abnormal in 23 of 81 patients (28.4%), mostly (21 of 23) with delayed GES. None of the tilt table test or autonomic results were predictive of abnormal antroduodenal manometry or GES. Analysis of EGD biopsy samples revealed nonspecific esophagitis and/or gastritis in 16 of 103 patients (15%).

CONCLUSIONS

Antroduodenal manometry with the tilt table test were the most insightful investigations in adolescents and young adults with orthostatic intolerance and gastrointestinal symptoms. GES and EGD provided limited information. Gastrointestinal symptoms were related more to functional rather than mucosal or organic etiologies, suggesting a limited role of endoscopy alone in evaluating patients with orthostatic intolerance presenting with gastrointestinal symptoms.

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

Postural tachycardia syndrome (POTS) is one of the most common causes of orthostatic intolerance and is being increasingly recognized in clinical practice. Gastrointestinal (GI) symptoms are reported commonly in patients with POTS and pose a considerable management challenge, making it imperative that gastroenterologists be aware of this condition and its GI comorbidities. Although the evidence presented herein does not prove causation, it does support an association between GI symptoms, GI dysmotility, and POTS. At present, the evaluation and treatment of GI symptoms in patients with POTS remains largely empirical. General measures to treat POTS may lead to improvement in both GI and non-GI symptoms. GI symptoms refractory to these measures should prompt further diagnostic evaluation of gastrointestinal dysmotility and appropriate dietary and pharmacologic management. This review focuses its attention on the involvement of the GI tract in POTS including a discussion of GI symptoms and conditions associated with POTS, followed by an analysis of abnormalities in gut physiology described in POTS, and concluding with an overview of management and suggestions for research directions.

The gastrointestinal symptoms present in patients with postural tachycardia syndrome: A review of the literature and overview of treatment

Orthostatic intolerance, including postural tachycardia syndrome, is often associated with gastrointestinal symptoms. In the vast majority of the cases, the gastrointestinal symptoms are not secondary to the orthostatic disorder, but rather just a comorbid condition. This concept is critical, since treatment aimed at the orthostatic condition will not improve the gastrointestinal symptoms. Only when the gastrointestinal symptoms develop in the upright position and improve or resolve in the supine position, they may be related to the orthostatic stress. The most common symptoms associated with orthostatic intolerance include nausea, dyspepsia, bloating and constipation. The majority of subjects do not have gastroparesis. The chapter discusses available treatments of these conditions.

Electrogastrography, Near-infrared Spectroscopy, and Acoustics to Measure Gastrointestinal Development in Preterm Babies

OBJECTIVES

The aim of the study was to obtain objective measures indicative of gastrointestinal maturity using 3 noninvasive technologies.

METHODS

Electrogastrography (EGG), abdominal near-infrared spectroscopy (NIRS), and bowel sound/acoustics (AC) monitoring were used simultaneously to obtain physiologic measures of the gastrointestinal system of 18 preterm and 5 term neonates who were tolerating enteral feedings. Measures of EGG slow wave voltage (EGG dominant power) and AC signal amplitude (AC dominant power) were obtained after spectral density analysis. Mean abdominal regional saturations (A-rSO2) were obtained directly from NIRS. The relationship of these 3 measures with postmenstrual age (PMA) was assessed.

RESULTS

The results of the 3 methods differed depending on whether the measurements were pre- or postprandial. Postprandial EGG dominant power increases with PMA (r = 0.67, P = 0.003), both pre- and postprandial abdominal NIRS mean regional saturation increase with PMA (r = 0.73, P < 0.001 and r = 0.55, P = 0.009), and postprandial AC dominant power (at 300-500 Hz) increases with PMA (r = -0.48, P = 0.025).

CONCLUSIONS

EGG, abdominal NIRS, and AC, whenever used simultaneously, can provide objective and synergistic measures that correlate with PMA. These findings may be helpful in the assessment of feeding readiness because they reveal quantitative measures suggestive of the developmental process of the gut.

Pediatric Disorders of Orthostatic Intolerance

Orthostatic intolerance (OI), having difficulty tolerating an upright posture because of symptoms or signs that abate when returned to supine, is common in pediatrics. For example, ∼40% of people faint during their lives, half of whom faint during adolescence, and the peak age for first faint is 15 years. Because of this, we describe the most common forms of OI in pediatrics and distinguish between chronic and acute OI. These common forms of OI include initial orthostatic hypotension (which is a frequently seen benign condition in youngsters), true orthostatic hypotension (both neurogenic and nonneurogenic), vasovagal syncope, and postural tachycardia syndrome. We also describe the influences of chronic bed rest and rapid weight loss as aggravating factors and causes of OI. Presenting signs and symptoms are discussed as well as patient evaluation and testing modalities. Putative causes of OI, such as gravitational and exercise deconditioning, immune-mediated disease, mast cell activation, and central hypovolemia, are described as well as frequent comorbidities, such as joint hypermobility, anxiety, and gastrointestinal issues. The medical management of OI is considered, which includes both nonpharmacologic and pharmacologic approaches. Finally, we discuss the prognosis and long-term implications of OI and indicate future directions for research and patient management.

Postural Tachycardia Syndrome: Diagnosis and Management in Adolescents and Young Adults

Postural tachycardia syndrome (POTS) represents a common form of orthostatic intolerance that disproportionately affects young women from puberty through adulthood. Patients with POTS have day-to-day orthostatic symptoms with the hallmark feature of an excessive, sustained, and symptomatic rise in heart rate during orthostatic testing. Although considerable overlap exists, three subtypes of POTS have been described: neuropathic, hyperadrenergic, and hypovolemic forms. The wide spectrum of symptoms and comorbidities can make treatment particularly challenging. Volume expansion with fluid and salt, exercise, and education constitute a reasonable initial therapy for most patients. Several medicines are also available to treat orthostatic intolerance and the associated comorbidities. Defining the POTS subtypes clinically in each patient may help to guide medicine choices. A multidisciplinary approach to overall management of the patient with POTS is advised. This review highlights several aspects of POTS with a specific focus on adolescent and young adult patients. [Pediatr Ann. 2017;46(4):e145-e154.].

Antroduodenal Manometry Is Abnormal in Children Presenting With Orthostatic Intolerance and Gastrointestinal Symptoms

OBJECTIVES

Gastrointestinal (GI) symptoms of nausea, vomiting, and abdominal pain are common in patients with orthostatic intolerance (OI), including neurally mediated hypotension (NMH) and postural orthostatic tachycardia syndrome (POTS). Autonomic dysregulation is considered the underlying pathophysiology behind the cardiovascular symptoms of POTS. Because the autonomic nervous system also regulates GI motility, we hypothesized that patients with POTS and GI symptoms will have evidence of autonomic dysmotility of the upper GI tract.

METHODS

Thirty-five subjects with OI and GI symptoms were studied. All the subjects had a 24-hour antroduodenal manometry (ADM) study, in conjunction with pharmacologic challenge and autonomic and tilt table testing (TTT).

RESULTS

The mean subject age was 16.2 ± 2.8 years (range 10-23.8 years), and male to female ratio was 10:25. TTT was abnormal in all the 35 subjects, whereas Valsalva testing was abnormal (+40 mmHG) in 21 of 34 (62%) subjects, and corrected QT interval was ≥0.44 seconds in 19 of 35 (54%) subjects. During TTT, GI symptoms were reproduced in 31 of 35 (89%) studies. ADM was found to be abnormal at baseline, before the TTT in 5 of 35 (14%) subjects, whereas it became abnormal in 23 of 34 (68%) subjects during TTT. In addition, the expected response to the pharmacologic challenge was limited. Overall, ADM was abnormal in 26 of 35 (74%) patients either at baseline or during TTT in these subjects with OI.

CONCLUSIONS

ADM is frequently abnormal in children with OI and GI symptoms. Upper GI motility studies should be a part of the comprehensive evaluation in this population.

Functional Nausea in Children: A Review of the Literature and Need for Diagnostic Criteria

Nausea is common amongst children with functional gastrointestinal disorders and is associated with a high burden of somatic and psychosocial comorbidities in both the short and long-term. Current treatments including medications, phytotherapy, stress-reduction techniques, and gastric electrical stimulation for recalcitrant cases, are reviewed. Functional nausea merits its own diagnostic criteria as a pediatric functional gastrointestinal disorder.

A survey-based analysis of symptoms in patients with postural orthostatic tachycardia syndrome

Postural orthostatic tachycardia syndrome (POTS) is a type of dysautonomia seen most commonly in young women and children. It is defined as an increase in heart rate of 30 beats per minute (bpm) or more within 10 minutes of standing in adults, or by 40 bpm or more in children in the absence of orthostatic hypotension. In addition to typical autonomic symptoms, POTS patients report a wide range of subjective complaints in multiple organ systems, though the exact frequencies are unclear. To address the symptom frequency, we had 39 patients with POTS at our institution complete an intake form consisting of a list of 37 symptoms. The most frequently reported symptoms included palpitations, lightheadedness, and headache, although sleep disturbances, gastrointestinal complaints, sensitivity to temperature, and rash were also common.

Relationship among nausea, anxiety, and orthostatic symptoms in pediatric patients with chronic unexplained nausea

This study evaluated the relationship among nausea, anxiety, and orthostatic symptoms in pediatric patients with chronic unexplained nausea. We enrolled 48 patients (36 females) aged 15 ± 2 years. Patients completed the Nausea Profile, State-Trait Anxiety Inventory for Children and underwent 70° head upright tilt testing (HUT) to assess for orthostatic intolerance (OI) and measure heart rate variability (HRV). We found nausea to be significantly associated with trait anxiety, including total nausea score (r = 0.71, p < 0.01) and 3 subscales: somatic (r = 0.64, p < 0.01), gastrointestinal (r = 0.48, p = 0.01), and emotional (r = 0.74, p < 0.01). Nausea was positively associated with state anxiety, total nausea (r = 0.55, p < 0.01), somatic (r = 0.48, p < .01), gastrointestinal (r = .30, p < .05), and emotional (r = .64, p < .01) subscales. Within 10 min of HUT, 27 patients tested normal and 21 demonstrated OI. After 45 min of HUT, only 13 patients (27%) remained normal. Nausea reported on the Nausea Profile before HUT was associated with OI measured at 10 min of tilt (nausea total r = 0.35, p < 0.05; nausea emotional subscale r = 0.40, p < 0.01) and lower HRV at 10 min of HUT (F = 6.39, p = 0.01). We conclude that nausea is associated with both anxiety symptoms and OI. The finding of decreased HRV suggests an underlying problem in autonomic nervous system function in children and adolescents with chronic unexplained nausea.

Effect of fludrocortisone acetate on chronic unexplained nausea and abdominal pain in children with orthostatic intolerance

BACKGROUND

We hypothesized that orthostatic intolerance (OI) is associated with gastric dysrhythmias, nausea, and abdominal pain, which improves using fludrocortisone to treat OI.

METHODS

Patients (n=16, girls) with OI completed questionnaires before and after fludrocortisone treatment (age 14.8 ± 2.8 years). Ten patients underwent electrogastrograms (EGGs) before fludrocortisone.

RESULTS

All EGGs showed gastric dysrhythmias. Fludrocortisone reduced mean scores as follows: nausea, 3.1 ± 0.8 to 2.1 ± 1.1 (P=0.016); dizziness, 3.0 ± 1.0 to 2.2 ± 1.1 (P=0.0371); abdominal pain, 2.8 ± 1.3 to 1.9 ± 1.4 (P=0.0063); flushing, 2.3 ± 1.2 to 1.5 ± 1.4 (P=0.0476); and missing school, 2.2 ± 1.5 to 1.2 ± 1.5 (P=0.0078).

CONCLUSIONS

Chronic nausea and abdominal pain accompany OI and improve with OI treatment.

Interstitial Cystitis - Elucidation of Psychophysiologic and Autonomic Characteristics (the ICEPAC Study): design and methods

BACKGROUND AND PURPOSE

Interstitial cystitis/bladder pain syndrome (IC/BPS) is relatively common and associated with severe pain, yet effective treatment remains elusive. Research typically emphasized the bladder's role, but given the high presence of systemic comorbidities, the authors hypothesized a pathophysiologic nervous system role. This paper reports the methodology and approach to study the nervous system in women with IC/BPS. The study compares neurologic, urologic, gynecologic, autonomic, gastrointestinal, and psychological features of women with IC/BPS, their female relatives, women with myofascial pelvic pain (MPP), and healthy controls to elucidate the role of central and peripheral processing.

METHODS AND RESULTS

In total, 228 women (76 IC/BPS, 76 MPP, 38 family members, and 38 healthy controls) will be recruited. Subjects undergo detailed screening, structured neurologic examination of limbs and pelvis, tender point examination, autonomic testing, electrogastrography, and assessment of comorbid functional dysautonomias. Interpreters are blinded to subject classification. Psychological and stress response characteristics are examined with assessments of stress, trauma history, general psychological function, and stress response quantification. As of December 2012, data collection is completed for 25 healthy controls, 33 IC/BPS ± MPP, eight MPP, and three family members. Recruitment rate is accelerating and strategies emphasize maintaining and encouraging investigator participation in study science, internet advertising, and presentations to pelvic pain support groups.

CONCLUSION

The study represents a comprehensive, interdisciplinary approach to sampling autonomic and psychophysiologic characteristics of women with IC/BPS. Despite divergent opinions on study methodologies based on specialty experiences, the study has proven feasible to date and different perspectives have proved to be one of the greatest study strengths.

Adolescent fatigue, POTS, and recovery: a guide for clinicians

Many teenagers who struggle with chronic fatigue have symptoms suggestive of autonomic dysfunction that may include lightheadedness, headaches, palpitations, nausea, and abdominal pain. Inadequate sleep habits and psychological conditions can contribute to fatigue, as can concurrent medical conditions. One type of autonomic dysfunction, postural orthostatic tachycardia syndrome, is increasingly being identified in adolescents with its constellation of fatigue, orthostatic intolerance, and excessive postural tachycardia (more than 40 beats/min). A family-based approach to care with support from a multidisciplinary team can diagnose, treat, educate, and encourage patients. Full recovery is possible with multi-faceted treatment. The daily treatment plan should consist of increased fluid and salt intake, aerobic exercise, and regular sleep and meal schedules; some medications can be helpful. Psychological support is critical and often includes biobehavioral strategies and cognitive-behavioral therapy to help with symptom management. More intensive recovery plans can be implemented when necessary.

Gastrointestinal manifestations of pediatric autonomic disorders

Functional gastrointestinal disorders (FGIDs) are currently classified under the Rome criteria based on symptoms and absence of organic disease. Preliminary studies have shown that FGIDs are probably not restricted to the GI tract, but may represent a systemic disorder with comorbidities affecting other parts of the body, including migraine, fatigue, aches and pains, etc. The autonomic nervous system (ANS) provides the extrinsic control of GI motility, secretions, and even immune response. The role of the ANS in the development of FGIDs and comorbidities is still unclear. Limited data demonstrate orthostatic intolerance such as reflex syncope and postural tachycardia syndrome in a large subset of subjects with FGIDs. Some studies have found improvement in the GI symptoms with treatment of the orthostatic intolerance it produces. Prospective studies are needed to determine the chronology of the development of the comorbidities, the triggers that induce these syndromes, and effective treatments. This chapter aims to review current understanding of the role of the ANS in FGIDs.

FGIDs in children are associated with many nonpsychiatric comorbidities: the tip of an iceberg?

Functional gastrointestinal disorders (FGIDs) are common. The poor health-related quality of life in FGIDs is a combination of gastrointestinal symptoms and comorbid conditions. We determined by using the Ohio Dysautonomia questionnaire the medical comorbidities in 38 children with FGID. Almost all of the subjects had a comorbid disorder, with orthostatic symptoms in 89%, fainted >3×/lifetime in 17%, headaches with migrainous features in 40%, other types of chronic pain in 50%, and fatigue lasting >6 months in approximately 33%. These findings constitute a critical first step in changing the paradigm of our approach to FGID as a broader systemic disorder, not one limited to the gastrointestinal tract.

Pediatric autonomic testing: retrospective review of a large series

OBJECTIVE. To describe the reasons for referral, autonomic diagnoses, test results, and patient management in a large pediatric population referred for testing for an autonomic disorder. DESIGN. The authors reviewed autonomic testing data and medical records for patients aged 18 years and younger who underwent testing between 1993 and 2007 and who had adequate clinical data. Relevance of test results to clinical symptoms was ranked on a 3-point scale. Treatments were noted and their benefit ranked on a 5-point scale. RESULTS. Among 142 pediatric patients identified, postural tachycardia syndrome was most common (71%) while orthostatic hypotension was rare (5%). Testing provided relevant information regarding the patient's symptoms in 88% of the cases. Beta-blockers were the most commonly prescribed medication (59%); 73% improved. CONCLUSIONS. Postural tachycardia syndrome was common in this large pediatric population, whereas orthostatic hypotension was infrequent. The symptomatic improvement in the majority bears an unclear relationship to treatment. Prospective studies are needed.

Comorbidities in pediatric patients with postural orthostatic tachycardia syndrome

OBJECTIVE

To investigate the frequency of various nonorthostatic complaints in children with postural orthostatic tachycardia syndrome (POTS).

STUDY DESIGN

We used our autonomic laboratory database to identify all pediatric patients with traditionally defined POTS who had completed the Ohio Dysautonomia Survey (ODYSA). The responses of the patients to questions targeting various autonomic complaints, including syncope, gastrointestinal symptoms, sleep disturbances, headaches, urinary symptoms, chronic pain, and Raynaud-like symptoms, were collected and analyzed.

RESULTS

A total of 53 pediatric patients completed the ODYSA questionnaire. The participants reported high frequencies of sleep abnormalities, chronic pain, Raynaud-like symptoms, and gastrointestinal abnormalities, with lower rates of headaches, syncope, and urinary complaints.

CONCLUSIONS

Our findings demonstrate the occurrence of various nonorthostatic symptoms in pediatric patients with POTS. These findings suggest the need for an interdisciplinary approach to the treatment and management of POTS, as well as for further investigation into the mechanisms that lead to the concurrent presentation of both orthostatic and nonorthostatic symptoms in these patients.