Cyclic vomiting syndrome: a brain-gut disorder

Cyclic vomiting syndrome: From pathophysiology to treatment

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent and unpredictable episodes of intense vomiting, interspersed with periods of apparent wellbeing. This disorder, which primarily affects children and adolescents but can persist into adulthood, has recently been the subject of extensive study and analysis in the medical literature. The aim of the present review is to examine the most important aspects of the epidemiology, pathophysiology, subtypes, diagnostic criteria, and current management of CVS. Even though the exact etiology remains unknown, genetic factors (polymorphisms), nervous system alterations and autonomic dysregulation, and environmental factors (use and abuse of cannabinoids) are postulated as possible triggers. CVS has significant diagnostic challenges, given that there is no specific test for confirming its presence. Thorough evaluation of symptoms and the ruling out of other possible causes of recurrent vomiting are required. Management of CVS typically involves a multidisciplinary approach. Pharmacologic options are explored, such as antiemetics and preventive medications, as well as behavioral and psychologic support therapies. Treatment personalization is essential, adapting it to the individual needs of each patient. Despite advances in the understanding of CVS, it remains a significant clinical challenge. This disorder impacts the quality of life of those affected and their families, underscoring the ongoing need for research and the development of more effective treatment strategies.

Treatment Options for Cyclic Vomiting Syndrome: A Real-World, Single-Center Experience with Systematic Literature Review and Meta-Analysis

The optimal therapeutic management of cyclic vomiting syndrome (CVS) remains elusive. The objective of this study was to document our clinical experience in the Pediatric Department of San Marco Hospital and to survey the literature on pediatric CVS treatment, aiming to update the guidance on the most effective treatment strategies for this not-so-uncommon condition. Data from 70 patients with CVS, admitted to our Pediatric Department between September 2011 and December 2021, were aggregated and included in the study. A systematic review of the literature was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool and the A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2) method. Treatment responses, as observed both in the literature and in our own experience, are variable. In our cohort, topiramate demonstrated superiority over other pharmacological treatments, exhibiting an efficacy of 85% in the patients treated. A universally accepted treatment protocol for pediatric CVS has yet to be established. The efficacy of first-line treatments is generally suboptimal, suggesting that topiramate might serve as a safe and effective primary therapeutic option for pediatric CVS.

Diagnosis and Management of Cyclic Vomiting Syndrome: A Critical Review

Cyclic vomiting syndrome (CVS) is a chronic disorder of gut-brain interaction characterized by recurrent disabling episodes of nausea, vomiting, and abdominal pain. CVS affects both children and adults with a prevalence of approximately 2% in the United States. CVS is more common in female individuals and affects all races. The pathophysiology of CVS is unknown and a combination of genetic, environmental, autonomic, and neurohormonal factors is believed to play a role. CVS is also closely associated with migraine headaches and likely have a shared pathophysiology. The diagnosis of CVS is based on the Rome criteria, and minimal recommended testing includes an upper endoscopy and imaging studies of the abdomen. CVS is frequently associated with anxiety, depression, and autonomic dysfunction. Patients with CVS commonly use cannabis therapeutically for symptom relief. By contrast, cannabinoid hyperemesis syndrome is believed to be a subset of CVS with chronic heavy cannabis use leading to hyperemesis. Due to the recalcitrant nature of the illness, patients often visit the emergency department and are hospitalized for acute CVS flares. Guidelines on the management of CVS recommend a biopsychosocial approach. Prophylactic therapy consists of tricyclic antidepressants (amitriptyline), antiepileptics (topiramate), and aprepitant in refractory patients. Abortive therapy consists of triptans, antiemetics (ondansetron), and sedation. Treatment of comorbid conditions is extremely important to improve overall patient outcomes. CVS has a significant negative impact on patients, families, and the healthcare system, and future research to understand its pathophysiology and develop targeted therapies is needed.

Relapse Rate of Clinical Symptoms After Stopping Treatment in Children with Cyclic Vomiting Syndrome

Background: Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder. It is characterized by recurrent episodes of vomiting typically separated by periods of symptom-free or baseline health. The present study aimed at evaluating the effectiveness of propranolol and the relapse rate of clinical symptoms after stopping treatment in children suffering from CVS. Methods: Records of 504 patients below the age of 18 years with CVS who were treated with propranolol from March 2008 to March 2018 were reviewed. The duration of follow-up was 10 years. Results: The average age of CVS affliction was 4.3 years and the average age at the diagnosis was 5.8 years. All subjects were treated with propranolol (for an average of 10 months). 92% of treated subjects were cured, causing a dramatic decrease in the rate of vomiting (P < 0.001). Only an average of 10.5% of the studied subjects (53 people) showed a relapse of symptoms after stopping the treatment. The results of a 10-year follow-up period of the patients showed that 24 had abdominal migraine and 6 had migraine headaches, all of whom lacked the symptoms of disease relapse (prognostic evaluation). Conclusion: The findings of this investigation show that the duration of treating CVS with propranolol could be shortened to 10 months with a low percent of symptoms relapse and this shortening may be effective in preventing the undesirable side effects of the drug. The presence of abdominal migraine and migraine headaches in patients after treatment accomplishment and the lack of disease relapse can be prognostic measures for this disease, which require intensive attention.

Current understanding of the etiology of cyclic vomiting syndrome and therapeutic strategies in its management

INTRODUCTION

Cyclic vomiting syndrome is a chronic debilitating disorder of the gut-brain interaction and is characterized by recurrent episodes of nausea and vomiting.Recent studies indicate that it is common and affects 2% of the US population. Unfortunately, there is significant heterogeneity in the management of these patients in the medical community. This review article aims to bridge this gap and will review the epidemiology and etiology with a focus on management of CVS.

AREAS COVERED

This article reviews the epidemiology, and pathophysiology of CVS and impact on patients. It also discusses management based on recent guidelines based on which is intended for the busy clinician. A literature search was done using PubMed and key words "cyclic vomiting", "management", "etiology", and pathophysiology were used to identify articles of importance.

EXPERT OPINION

CVS is a complex, poorly understood disorder of gut-brain interaction (DGBI) and has a significant negative impact on patients, families and the healthcare system. Recent guidelines recommend a multidisciplinary approach to management using prophylactic therapy in moderate-severe CVS and abortive medication for acute flares. However more research is needed to better understand the pathophysiology and develop targeted therapies for CVS.

CURRENT PERSPECTIVES ON MITOCHONDRIAL DYSFUNCTION IN MIGRAINE

Mitochondria is an autonomous organelle that plays a crucial role in the metabolic aspects of a cell. Cortical Spreading Depression (CSD) and fluctuations in the cerebral blood flow have for long been mechanisms underlying migraine. It is a neurovascular disorder with a unilateral manifestation of disturbing, throbbing and pulsating head pain. Migraine affects 2.6 and 21.7% of the general population and is the major cause of partial disability in the age group 15-49. Higher mutation rates, imbalance in concentration of physiologically relevant molecules, oxidative stress biomarkers have been the main themes of discussion in determining the role of mitochondrial disability in migraine. The correlation of migraine with other disorders like hemiplegic migraine, MELAS, TTH, CVS, ischemic stroke and hypertension has helped in the assessment of the physiological and morphogenetic basis of migraine. Here, we have reviewed the different nuances of mitochondrial dysfunction and migraine. The different mtDNA polymorphisms that can affect the generation and transmission of nerve impulse has been highlighted and supported with research findings. In addition to this, the genetic basis of migraine pathogenesis as a consequence of mutations in nuclear DNA that can in turn affect the synthesis of defective mitochondrial proteins is discussed along with a brief overview of epigenetic profile. This review gives an overview of the pathophysiology of migraine and explores mitochondrial dysfunction as a potential underlying mechanism. Also, therapeutic supplements for managing migraine have been discussed at different junctures in this paper.

Faecal Microbiota in Infants and Young Children with Functional Gastrointestinal Disorders: A Systematic Review

Functional gastrointestinal disorders (FGIDs) refer to gastrointestinal tract issues that lack clear structural or biochemical causes. Their pathophysiology is still unclear, but gut microbiota alterations are thought to play an important role. This systematic review aimed to provide a comprehensive overview of the faecal microbiota of infants and young children with FGIDs compared to healthy controls. A systematic search and screening of the literature resulted in the inclusion of thirteen full texts. Most papers reported on infantile colic, only one studied functional constipation. Despite methodological limitations, data show alterations in microbial diversity, stability, and colonisation patterns in colicky infants compared to healthy controls. Several studies (eight) reported increases in species of (pathogenic) Proteobacteria, and some studies (six) reported a decrease in (beneficial) bacteria such as Lactobacilli and Bifidobacteria. In addition, accumulation of related metabolites, as well as low-grade inflammation, might play a role in the pathophysiology of infantile colic. Infants and toddlers with functional constipation had significantly lower levels of Lactobacilli in their stools compared to controls. Microbial dysbiosis and related changes in metabolites may be inherent to FGIDs. There is a need for more standardised methods within research of faecal microbiota in FGIDs to obtain a more comprehensive picture and understanding of infant and childhood FGIDs.

Association of Mitochondrial DNA Polymorphisms With Pediatric-Onset Cyclic Vomiting Syndrome

BACKGROUND

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder characterized by recurrent stereotypic episodes of vomiting. The pathophysiology of CVS remains obscure. Previous studies have supported the hypotheses of mitochondrial dysfunction. However, data on association studies between mitochondrial DNA (mtDNA) polymorphisms and pediatric-onset CVS are limited and inconsistent. The aims of this study were to describe clinical characteristics, evaluate association of mtDNA polymorphisms 16519T and 3010A with pediatric-onset CVS and identify new mtDNA candidate variants.

METHODS

This study involved Thai patients diagnosed with CVS according to the Rome III or IV criteria before the age of 15 years. Patients' demographic data, clinical characteristics, previous investigations and treatment outcomes were obtained. Blood samples were collected for next-generation (whole exome) sequencing, followed by analysis of chromosome M (mitochondrial. Variants were filtered according to clinical significance using ClinVar and MITOMAP. mtDNA polymorphisms in 148 normal Thai individuals were used as controls.

RESULTS

Forty-eight children were enrolled in the clinical study, and 30 participated in the genetic analysis. The median age at onset and median age at diagnosis was 3.0 (1.5-5.6) and 6.3 (3.0-8.6) years, respectively. Maternal history of migraine was positive in 16.7%. About 45.7% (21 of 46) of the patients achieved complete clinical remission, with the mean symptom duration of 5.9 ± 3.3 years. The prevalence of mtDNA variants 16519T and 3010A among the patient group and Thai general population (control) were as follows: 40.0% (12/30) vs. 27.7% (P = 0.18) and 6.7% (2/30) vs. 0.7% (P = 0.07), respectively. Five known pathogenic variants were identified in 6 patients, including mtDNA 8528C in one patient who also had infantile hypertrophic cardiomyopathy. Six likely pathogenic variants were found but without statistical significance. We identified 11 variants with significant prevalence in the patient group. Though, these variants were classified as variants of unknown significance (VUS), several of them were located in mt functional regions and therefore they deserve further investigations as new candidates for association with pediatric CVS.

CONCLUSION

There were no associations of mtDNA polymorphisms 16519T and 3010A with CVS in our pediatric cohort. Five pathogenic variants and 11 VUS were found associated with pediatric-onset CVS.

Adult Abdominal Migraine Improved by OnabotulinumtoxinA Injections

Abdominal migraine is often regarded as a childhood disorder and less commonly described in adults. However, gastrointestinal symptoms are known to occur to adult migraine patients, and recognition of adult abdominal migraine may facilitate treatment of the recurrent abdominal symptoms and avoidance of unproductive and sometimes invasive therapies. Here, I describe a patient with chronic migraine headaches and recurrent abdominal pain both of which showed sustained improvement after treatment with onabotulinumtoxinA injections.

Nausea-Induced Conditioned Gaping Reactions in Rats Produced by High-Dose Synthetic Cannabinoid, JWH-018

Introduction: Cannabinoid hyperemesis syndrome is becoming a more prominently reported side effect of cannabis containing high-dose Δ⁹-tetrahydrocannabinol (THC) and designer cannabinoid drugs such as "Spice." One active ingredient that has been found in "Spice" is 1-pentyl-3-(1-naphthoyl)indole (JWH-018), a synthetic full agonist of the cannabinoid 1 (CB₁) receptor. In this study, we evaluated the potential of different doses of JWH-018 to produce conditioned gaping in rats, an index of nausea. Materials and Methods: Rats received 3 daily conditioning trials in which saccharin was paired with JWH-018 (0.0, 0.1, 1, and 3 mg/kg, intraperitoneal [i.p.]). Then the potential of pretreatment with the CB₁ antagonist, rimonabant (SR), to prevent JWH-018-induced conditioned gaping was determined. To begin to understand the potential mechanism underlying JWH-018-induced nausea, serum collected from trunk blood was subjected to a corticosterone (CORT) analysis in rats receiving three daily injections with vehicle (VEH) or JWH-018 (3 mg/kg). Results: At doses of 1 and 3 mg/kg (i.p.), JWH-018 produced nausea-like conditioned gaping reactions. The conditioned gaping produced by 3 mg/kg JWH-018 was reversed by pretreatment with rimonabant, which did not modify gaping on its own. Treatment with JWH-018 elevated serum CORT levels compared to vehicle-treated rats. Conclusions: As we have previously reported with high-dose THC, JWH-018 produced conditioned gaping in rats, reflective of a nausea effect mediated by its action on CB₁ receptors and accompanied by elevated CORT, reflective of hypothalamic-pituitary-adrenal (HPA) activation.

Cyclic Vomiting Syndrome: A Case Report and Mini Literature Review

A 27-year-old man presented to the emergency department with nausea, vomiting, and abdominal pain. He had been having similar episodes for the last seven years, and all of the previous workups had been unremarkable. After excluding all organic causes of his presentation, the patient was diagnosed with cyclic vomiting syndrome (CVS) and managed accordingly. He has shown remarkable improvement and no further attack has been reported for almost five months since the diagnosis was made. This case report highlights the diagnostic challenge represented by CVS. Also, it summarizes the main aspects of management to achieve and maintain the remission of the condition.

Cannabinoid Hyperemesis Syndrome: A Review of Potential Mechanisms

Introduction: Cannabinoids have long been known for their ability to treat nausea and vomiting. Recent reports, however, have highlighted the paradoxical proemetic effects of cannabinoids. Cannabinoid hyperemesis syndrome (CHS) is characterized by cyclical episodes of nausea and vomiting, accompanied by abdominal pain following prolonged, high-dose cannabis use, which is alleviated by hot baths and showers. Little is known about the cause of this syndrome. Discussion: Cannabinoids produce a biphasic effect on nausea and vomiting, with low doses having an antiemetic effect and high doses producing emesis. Presentation and treatment of CHS are similar to cyclical vomiting syndrome as well as chemotherapy-related anticipatory nausea and vomiting, suggesting that these phenomena may share mechanisms. The prevalence of CHS is not known because of the symptomatic overlap with other disorders and the lack of knowledge of the syndrome by the public and physicians. Treatment with typical antiemetic drugs is ineffective for CHS, but anxiolytic and sedative drugs, along with hot showers, seem to be consistently effective at reducing symptoms. The only known way to permanently end CHS, however, is abstinence from cannabinoids. Case studies and limited pre-clinical data on CHS indicate that prolonged high doses of the main psychotropic compound in cannabis, Δ9-tetrahydrocannabinol (THC), result in changes to the endocannabinoid system by acting on the cannabinoid 1 (CB1) receptor. These endocannabinoid system changes can dysregulate stress and anxiety responses, thermoregulation, the transient receptor potential vanilloid system, and several neurotransmitters systems, and are thus potential candidates for mediating the pathophysiology of CHS. Conclusions: Excessive cannabinoid administration disrupts the normal functioning of the endocannabinoid system, which may cause CHS. More clinical and pre-clinical research is needed to fully understand the underlying pathophysiology of this disorder and the negative consequences of prolonged high-dose cannabis use.

Cyclic vomiting syndrome: an overview for clinicians

Introduction: Cyclic vomiting syndrome (CVS) is an under recognized entity causing significant impact on patient's lifestyle. CVS is characterized by recurrent episodes of abdominal pain, nausea, and vomiting leading to many emergency department presentations prior to diagnosis. Patients often have lengthy delays in starting appropriate therapy leading to significant physical and financial hardship. Most cases of cyclic vomiting syndrome are reversible by managing risk factors and starting on appropriate treatment.Areas covered: This review covers the diagnostic criteria, pathophysiology, risk factors, and treatment for CVS and provides a valuable resource for clinicians to review and help with managing this challenging syndrome. The latest literature regarding the diagnosis and management of CVS is summarized.Expert Opinion: The direction for future research in CVS and insights to managing CVS are summarized. The role of pain that can be frequently controlled by tricyclic antidepressants and lorazepam suggests a central nervous system (CNS) origin. A standardized treatment regimen for CVS must be implemented as patients do respond to current therapies but there is often a significant delay in initiation of treatment. Reviewed recent data looking at MRI brain changes in patients with CVS that may lead to a better understanding of the pathophysiology of this disease.

Acute Management of Pediatric Cyclic Vomiting Syndrome: A Systematic Review

OBJECTIVES

To synthesize quantitative and qualitative data on pharmacologic interventions of pediatric cyclic vomiting syndrome and their effectiveness in disease management in the acute care setting.

STUDY DESIGN

Using keywords, 799 studies published up from December 1954 to February 2018 were extracted from MEDLINE via Pubmed, Embase via OVID, CINAHL via EBSCO, and Cochrane Controlled Trials Registry. Studies were evaluated for inclusion and exclusion by 2 independent reviewers using predetermined inclusion and exclusion criteria.

RESULTS

The search yielded 84 studies for full review, of which 54 were included in the systematic review. Studies were subsequently separated into 1 group of 6 case series studies containing quantitative data on sumatriptan, ondansetron, phenothiazines, prokinetic agents, carbohydrate, isometheptene, and aprepitant; 1 one group consisting only of qualitative studies containing expert recommendations.

CONCLUSIONS

Ondansetron has the most quantitative and qualitative evidence to support its inclusion in pediatric emergency department protocols as a rescue therapy. Sumatriptan and aprepitant are potential candidates for inclusion as abortive therapies. Qualitative data from retrospective studies and case reports are not applicable to a larger patient population. This report informs a need for controlled, prospective cohort studies and randomized, controlled trials to optimize current management protocols and to develop new medical interventions.

Catamenial cyclic vomiting syndrome responding to oestrogen therapy: an adolescent case report

Cyclic vomiting syndrome (CVS) is defined by episodes of vomiting lasting from a few hours to several days, alternating with periods of no symptoms. Various symptoms can be associated with vomiting such as nausea, migraine or abdominal pain. Common triggers of CVS include infection, psychological stress and menstruation. CVS's diagnosis requires exclusion of alternative diseases particularly neurological and gastrointestinal. CVS shares many common features with catamenial migraine including treatment. We herein report a case of CVS in a 16 years old girl characterized by stereotypical vomiting attacks occurring in every menstrual period. Recurrent vomiting episodes began 2 years before admission. Given the negativity of paraclinical exams and the absence of response to different therapeutic approaches as well as the similarity with catamenial migraine, we treated our patient with permenstrual percutaneous oestrogen for six months. The evolution was marked by the disappearance of symptoms within the first month and the absence of their recurrence after treatment cessation during a follow-up of 6 years.

Guidelines on management of cyclic vomiting syndrome in adults by the American Neurogastroenterology and Motility Society and the Cyclic Vomiting Syndrome Association

The increasing recognition of cyclic vomiting syndrome (CVS) in adults prompted the development of these evidence-based guidelines on the management of CVS in adults, which was sponsored by the American Neurogastroenterology and Motility Society (ANMS) and the Cyclic Vomiting Syndrome Association (CVSA). GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework was used and a professional librarian performed the literature search. The expert committee included the President of the CVSA who brought a patient perspective into the deliberations. The committee makes recommendations for the prophylaxis of CVS, treatment of acute attacks, diagnosis, and overall management of CVS. The committee strongly  recommends that adults with moderate-to-severe CVS receive a tricyclic antidepressant (TCA), such as amitriptyline, as a first-line prophylactic medication and receive topiramate or aprepitant as alternate prophylactic medications. Zonisamide or levetiracetam and mitochondrial supplements (Coenzyme Q10, L-carnitine, and riboflavin) are conditionally recommended as alternate prophylactic medications, either alone or concurrently with other prophylactic medications. For acute attacks, the committee conditionally recommends using serotonin antagonists, such as ondansetron, and/or triptans, such as sumatriptan or aprepitant to abort symptoms. Emergency department treatment is best achieved with the use of an individualized treatment protocol and shared with the care team (example provided). The committee recommended screening and treatment for comorbid conditions such as anxiety, depression, migraine headache, autonomic dysfunction, sleep disorders, and substance use with referral to appropriate allied health services as indicated. Techniques like meditation, relaxation, and biofeedback may be offered as complementary therapy to improve overall well-being and patient care outcomes.

The efficacy and duration of treatment with propranolol in children with cyclic vomiting syndrome in southern Iran

INTRODUCTION

Cyclic vomiting syndrome is a functional disorder characterised by repeated episodes of nausea and vomiting with symptom-free intervals between the attacks. Cyclic vomiting syndrome is a migraine equivalent; therefore, anti-migraine medications are effective for cyclic vomiting syndrome prophylaxis, but duration of treatment is not clear.

AIM

To determine the efficacy and duration of drug therapy in cyclic vomiting syndrome.

MATERIAL AND METHODS

This study was conducted on 206 cases of cyclic vomiting syndrome, who were treated with propranolol as prophylaxis. After they were symptom-free for at least 9 months, propranolol was tapered and discontinued and then they were followed for at least 6 months after drug withdrawal for evaluation of recurrence.

RESULTS

The study subjects included 127 boys and 79 girls. The mean age of symptom onset was 3.4 years (range: 3 months to 14.5 years) and the mean age at the time of diagnosis was 5.7 years (range: 8.4 months to 18 years). Among the 206 patients in whom propranolol was discontinued, only 16 (7.8%) subjects developed recurrence of symptoms in the 6-month follow-up period.

CONCLUSIONS

There is no need to continue prophylaxis of cyclic vomiting syndrome for a long time. It is also possible to make the duration of drug therapy shorter, which is useful for the convenience of the patients and prevention of drug side effects.

[Cyclic vomiting syndrome in children]

Cyclic vomiting syndrome (CVS) is a misrecognized and probably underdiagnosed disease that can affect up to 1.9% of the pediatric population and can occupy 15% of these children's time. It is characterized by acute attacks of vomiting, occurring with such a strict frequency that some parents can predict the date of their child's next attack. The pathophysiology of CVS is unclear, although the literature recognizes a common origin with migraine headaches, which has the same acute and prophylactic treatment. CVS is now included in the larger group of diseases called "episodic symptoms related to migraine" previously known as "childhood periodic syndromes." To distinguish between real CVS and other differential diagnoses can challenge the clinician. Additional investigations must be considered in accordance with the clinical presentation. Appropriate management of CVS should lead to an improvement in quality of life and school attendance.

Cyclical Vomiting Syndrome: Psychiatrist's View Point

Cyclical vomiting syndrome (CVS) is an idiopathic functional disorder characterized by recurrent episodes of nausea and vomiting separated by symptom-free intervals. Even though initially described in children, it is seen in all age groups. Exact etiology is not known. Various physical, infectious, and psychosocial stressors have been implicated for CVS. High incidence of psychiatric comorbidities such as panic attacks, anxiety disorder, and depression is seen in CVS. Most children outgrow CVS with time though some may transition to migraine or continue to have CVS as adults. Frequent misdiagnosis, delay in diagnosis, or inadequate treatment often lead to years of recurrent vomiting. This case report highlights the importance of the management of CVS by a multidisciplinary team including a psychiatrist in addressing the various physical and psychological factors effectively and that would result in faster and prolonged recovery.

Gastric Electrical Stimulation Is an Option for Patients with Refractory Cyclic Vomiting Syndrome

Background/Aims

Cyclic vomiting syndrome (CVS) is a disabling migraine variant manifesting as severe episodes of nausea and vomiting and often refractory to many therapies. Gastric electrical stimulation (GES), which can reduce nausea and vomiting in gastroparesis, may provide symptomatic relief for drug-refractory CVS. This study assessed the utility GES in reducing the symptoms of CVS and improving the quality of life.

Methods

A one-year, non-randomized, clinical study was conducted. Eleven consecutive patients with drug refractory, cyclic vomiting syndrome based on Rome III criteria and North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN), underwent treatment with temporary GES (Temp GES) and permanent GES (Perm GES). Post-treatment follow up was done up to one year after permanent gastric electrical stimulation therapy.

Results

Total symptom score decreased by 68% and 40% after temporary and permanent GES therapies, respectively. Hospital admission events significantly decreased to 1.50 (± 1.00) events from 9.14 (± 7.21) annual admissions prior to treatment with permanent GES. Vomiting episodes fell by 83% post Temp GES and 69% after Perm GES treatments. Mucosal electrogram values also changed after temporary stimulation.

Conclusions

In a small group of drug-refractory CVS patients, treatments with temporary and permanent GES significantly reduced the severity of gastrointestinal symptoms and frequency of hospital admissions.

The Cyclic Vomiting Syndrome Threshold: A Framework for Understanding Pathogenesis and Predicting Successful Treatments

Cyclic vomiting syndrome (CVS) is an uncommon, idiopathic disorder defined by recurrent, sudden-onset attacks of repetitive retching and vomiting that are separated by symptom-free intervals. CVS was long regarded as a disorder primarily experienced by children but is now known to present de novo in adulthood. Adult CVS has garnered more research attention over the past 20 years, and these efforts have identified some acute and prophylactic treatments for this disorder. However, CVS still lacks a unifying disease model, and this has hindered the development of new therapies. Here adult CVS is reframed as a neurogenic disorder, driven by various endophenotypic factors that shape patterns of activity within the neural circuits required for disease expression. The concept of the "CVS threshold" is put forth in parallel with exploring the remarkable similarity of adult CVS with features of chronic migraine, epilepsy, and panic disorder. Because of such shared neural mechanisms and overlapping endophenotypes, many therapies that have been developed for these other disorders could also be useful in managing CVS. This review seeks to achieve three primary aims: (1) to develop a comprehensive, explanatory framework for adult CVS pathogenesis, (2) to use this framework for identifying potentially novel therapies for CVS, and (3) to describe future research directions that are needed to move the field forward.

Cyclic Vomiting Syndrome in Infants and Children: A Clinical Follow-Up Study

BACKGROUND

Cyclic vomiting syndrome is characterized by recurrent vomiting that is associated with increased adrenocorticotropic hormone and antidiuretic hormone levels during cyclic vomiting syndrome attacks. However, both prognosis and treatment remain unclear. We therefore evaluated the clinical features, prognosis, and effectiveness of the prophylaxis of cyclic vomiting syndrome as well as the relationship between symptoms and adrenocorticotropic hormone/antidiuretic hormone levels.

METHODS

We included 31 patients with cyclic vomiting syndrome who were admitted to Teikyo University between 1996 and 2008. All patients were diagnosed with cyclic vomiting syndrome based on the criteria of the second edition of the International Headache Classification. The patients (25 of 31) were followed until 2013.

RESULTS

The median overall duration of the disorder was 66 (3-179) months. Follow-up was completed for 25 patients with cyclic vomiting syndrome, of whom 44% (n = 11) developed migraine. Valproic acid, valproic acid with phenobarbital, phenobarbital, and amitriptyline were effective in nine, four, three, and one patients, respectively. Abnormally high adrenocorticotropic hormone (n = 17) and antidiuretic hormone (n = 18) levels were found among the 25 patients for whom follow-up data were available. The following correlations were significant: attack duration and adrenocorticotropic hormone levels (correlation coefficient: 0.5153, P = 0.0084) and attack duration and antidiuretic hormone levels (correlation coefficient: 0.5666, P = 0.0031). Antidiuretic hormone levels in patients with bilious vomiting were higher than in those without bilious vomiting (P = 0.048).

CONCLUSIONS

Most patients with cyclic vomiting syndrome recovered completely and benefited from prophylactic therapy, although half of them developed migraines.

Definitions and Outcome Measures in Pediatric Functional Upper Gastrointestinal Tract Disorders: A Systematic Review

OBJECTIVES

Functional disorders of the upper gastrointestinal tract are frequently diagnosed in children. Four different clinical entities are addressed by the Rome III committee: functional dyspepsia (FD), cyclic vomiting syndrome (CVS), adolescent rumination syndrome (ARS), and aerophagia. Management of these disorders is often difficult leading to a wide variety in therapeutic interventions. We hypothesize that definitions and outcome measures in these studies are heterogeneous as well. Our aim is to systematically assess how these disorders and outcomes are defined in therapeutic randomized controlled trials (RCTs).

STUDY DESIGN

CENTRAL, Embase, and MEDLINE/PubMed were searched from inception to February 25, 2015. Search terms were FD, CVS, ARS, and aerophagia. Therapeutic RCTs, or systematic reviews of RCTs, in English language including subjects ages 4 to 18 years (0-18 years for CVS) were evaluated. Quality was assessed using the Delphi list.

RESULTS

A total of 1398 articles were found of which 8 articles were included. Seven concerned FD and 1 concerned CVS. In all of the studies, Rome criteria or similar definitions were used; all the studies however used different outcome measures. Seventy-five percent of the trials were of good methodological quality. Only 57% used validated pain scales.

CONCLUSIONS

Different outcome measures are used in therapeutic trials on functional disorders of the upper gastrointestinal tract. There is a clear paucity of trials evaluating different treatment regimens regarding CVS, ARS, and aerophagia. Uniform definitions, outcome measures, and validated instruments are needed to make a comparison between intervention studies possible.

The Episodic Syndromes That Maybe Associated with Migraines

The "childhood periodic syndromes" have been renamed "the episodic syndromes that maybe associated with migraines". These syndromes were initially considered precursors of migraines that only occurred in childhood; however recent literature suggests that the episodic syndromes can occur in adults with known migraine and does not necessarily present as a precursor. This review article discusses the recent literature regarding the episodic syndromes and potential treatments. These disorders are seen by multiple subspecialists, therefore it is important to recognize and use the same definitions, criteria and nomenclature. A collaborative and multidisciplinary approach is critical to characterize, manage and potentially improve outcomes.

Riboflavin in cyclic vomiting syndrome: efficacy in three children

Cyclic vomiting syndrome is an episodic disorder considered to be a migraine variant. Riboflavin is efficient in the prophylactic treatment of migraines in adults. We describe the effectiveness and tolerance of riboflavin treatment in three children with cyclic vomiting syndrome. All of them fulfilled the diagnosis criteria for cyclic vomiting syndrome. They received prophylactic monotherapy with riboflavin for at least 12 months. Excellent response and tolerability was observed.

CONCLUSION

Based on clinical observation in three cases, riboflavin may be an effective and safe prophylactic treatment for children with cyclic vomiting syndrome.

WHAT IS KNOWN

CVS is one of the "childhood periodic syndromes" classified as a migraine subtype by the International Headache Society. Riboflavin is currently used as a prophylactic treatment in patients with migraine.

WHAT IS NEW

Riboflavin may be an effective and safe prophylactic treatment for children with CVS. Increasing doses of riboflavin and long periods of prophylaxis may be needed in some children..

Cyclic Vomiting Syndrome

Cyclic vomiting syndrome (CVS) consists of recurrent paroxysms of severe nausea and vomiting separated by symptom-free periods. A 12-year-old boy presented with recurrent vomiting over a period of 3 years. Episodes occurred over a period of 6 months, and the patient remained normal for next 6 months. About 8 such episodes occurred in the last 6 months. Physical and neurological examinations were normal. All routine investigations were normal. He was started on cognitive behavioral therapy and cyproheptadine and improved gradually. CVS is considered a functional brain-gut disorder and is characterized by recurrent, sudden, stereotypical, disabling, discrete episodes of intense nausea and vomiting that can last a few hours to days interspersed with varying weeks of symptom-free intervals. Integrated treatment combining pharmacological, psychotherapeutic, psycho-educational and lifestyle aspects as well as family therapy provides the best chances of successful treatment.

Anxiety Measures Predict Health-Related Quality of Life in Children and Adolescents with Cyclic Vomiting Syndrome

OBJECTIVE

To evaluate the relationship between anxiety and health-related quality of life (HRQoL) in children and adolescents with cyclic vomiting syndrome (CVS).

STUDY DESIGN

Forty children aged 8-18 years diagnosed with CVS and 40 parents completed the Screen for Child Anxiety Related Emotional Disorders (SCARED) and the child and parent forms of the Pediatric Quality of Life Generic Core Scale, a measure of HRQoL.

RESULTS

Eleven of the 40 children (27%) by self-report and 6 of 40 (15%) by parent-proxy report met the clinical cutoff for an anxiety disorder on the SCARED. Parent and child SCARED ratings were moderately correlated (intraclass correlation coefficient 0.68; P < .001). Child-rated HRQoL (mean ± SD, 74.3 ± 15.2) and parent-rated HRQoL (mean, 72.1 ± 14.6) were lower than healthy norms (P < .001). Disease severity (mean duration of CVS episodes, 3 ± 2.4 days), annual frequency of CVS episodes (mean, 8.2 ± 15.3), chronicity of CVS (mean, 5.8 ± 3.4 years), and delay in diagnosis (mean, 2.4 ± 1.9 years) were not associated with child-reported HRQoL; however, child SCARED scores accounted for approximately 50% of the variance in child-reported HRQoL (adjusted R(2) = 0.49; df = 1, 38; P < .001).

CONCLUSION

Children and adolescents with CVS appear to be at increased risk for anxiety. Anxiety symptoms are a stronger predictor of HRQoL than disease characteristics in children and adolescents with CVS. Assessment and treatment of anxiety in children and adolescents with CVS may have a positive impact on HRQoL.

Pediatric migraine and episodic syndromes that may be associated with migraine

Importance

Migraine is a common disorder and a frequent cause of medical consultation in children. Many childhood episodic syndromes have been described as common precursors of migraine.

Objective

To review current knowledge on migraine and childhood episodic syndromes, and to discuss future directions for research and clinical practice.

Findings

For most children it is difficult to describe a headache and fully verbalize symptoms such as photophobia and phonophobia that must be inferred from behaviour. Classical migraine features are rare before the age of 6 years, but some migraine-related syndromes have been described. Benign paroxysmal torticollis of infancy, benign paroxysmal vertigo of childhood, cyclic vomiting syndrome and abdominal migraine are currently classified as childhood episodic syndromes, and therefore common precursors of migraine. A strong association between infantile colic and migraine has recently been reported. There are similarities between children with episodic syndromes and children with migraine, regarding social and demographic factors, precipitating and relieving factors, and accompanying gastrointestinal, neurologic, and vasomotor features. The real pathophysiological mechanisms of migraine are not fully understood. Current data obtained through molecular and functional studies provide a complex model in which vascular and neurologic events cooperate in the pathogenesis of migraine attacks. Genetic factors causing disturbances in neuronal ion channels, make a migraineur more sensitive to multiple trigger factors that activate the nociception cascade. The expanding knowledge on migraine genetics and pathophysiology may be applicable to childhood episodic syndromes. Migraine preventive strategies are particularly important in children, and could be beneficial in childhood episodic syndromes. Nonspecific analgesics like ibuprofen and acetaminophen are widely used in pediatrics to control pain and have been found to be effective also in the treatment of acute migraine attacks. Triptans are the specific fist-line drugs for acute migraine treatment.

Conclusions and relevance

Migraine phenotype differs somewhat in the developing brain, and childhood episodic syndromes may arise before typical migraine headache. Diagnosing pediatric migraine may be difficult because of children’s language and cognitive abilities. The risk of underestimating migraine in pediatric age is high. An adequate diagnosis is important to maintain a good quality of life and to avoid inappropriate therapy.

Efficacy of the neurokinin-1 receptor antagonist aprepitant in children with cyclical vomiting syndrome

BACKGROUND

Aprepitant (Emend, Merck Sharp & Dohme Ltd, Haarlem, the Netherlands), a neurokinin-1 receptor antagonist, prevents vomiting in a range of conditions. No data are available on its use in children with cyclical vomiting syndrome (CVS).

AIM

We investigated the efficacy of aprepitant as prophylactic treatment or acute intervention in CVS children refractory to conventional therapies.

METHODS

Forty-one children (median age: 8 years) fulfilling NASPGHAN criteria treated acutely (RegA) or prophylactically (RegP) with aprepitant were retrospectively reviewed. Primary outcome was the clinical response (decrease in frequency and intensity of CVS episodes). Secondary outcomes were: number of CVS episodes/year, number of hospital admissions/year, CVS episode duration, number of vomits/h, symptom-free interval length (days), and school attendance percentage. The follow-up period was 18-60 months.

RESULTS

Sixteen children received RegP and 25 RegA. One child on RegP stopped treatment due to severe migraine. At 12-months on intention-to-treat analysis, 13 children on RegP (81%) achieved either complete (3/16, 19%) or partial (10/16, 62%) clinical response. On RegA, 19 children (76%) had either complete (3/25, 12%) or partial (16/25, 64%) response (P = 0.8 vs. RegP). In both RegP and RegA, there was a significant decrease in CVS episodes/year, hospital admission number/year, CVS episode length, number of vomits/h, as well as an increase in symptom-free interval duration and school attendance percentage. Side effects were reported only in RegP (5/16, 31%) including hiccough (3/16, 19%), asthenia/fatigue (2/16, 12.5%), increased appetite (2/16, 12.5%), mild headache (1/16, 6%) and severe migraine (1/16, 6%).

CONCLUSION

Aprepitant appears effective for both acute and prophylactic management of paediatric cyclical vomiting syndrome refractory to conventional therapies.

Approach to the diagnosis and treatment of cyclic vomiting syndrome: a large single-center experience with 106 patients

BACKGROUND

Cyclic vomiting syndrome is characterized by repeated, stereotypical vomiting episodes. The diagnosis is made by exclusion of other organic diseases, which can lead to extensive testing. It has been suggested that these patients can have mitochondrial dysfunction. The aim of the study was to examine the evaluation of our cyclic vomiting patients and to determine whether they had associated, undiagnosed metabolic abnormalities.

METHODS

This retrospective study included 106 patients aged <21 years at diagnosis. Information regarding medical history, laboratory, and imaging studies were collected. Metabolic studies in plasma and urine were obtained when patients were well and when patients were in a vomiting cycle, including plasma amino acids, acylcarnitines, and urine organic acids.

RESULTS

The mean age at diagnosis was 8.9 ± 5.0 years. Neuroimaging revealed previously unknown intracranial abnormalities in <10% of patients, none of whom explained the vomiting signs. Abdominal ultrasounds revealed abnormalities in 15% of patients during an acute episode and 7% of patients when well. Sixty-one patients had an upper gastrointestinal series, all of which were normal. A total of 92% of patients had laboratory testing with 38% indicating abnormalities possibly suggesting mitochondrial dysfunction.

CONCLUSIONS

This large, single-center study further evaluated the need for more focused evaluation in patients with suspected cyclic vomiting syndrome. Thirty-eight percent of our patients had abnormalities in blood and/or urine suggesting mitochondrial dysfunction, which requires more detailed investigation in the future.

Migraine-related symptoms in childhood

Periodic disorders of childhood often represent precursors of migraine. As we advance our knowledge of migraine and its complicated phenotypic presentation in childhood, we have noted the similarities in overlapping symptoms of children presenting with childhood periodic syndromes. There is often a positive family history of migraine in children that present with periodic syndromes. There is a known transformation of periodic syndromes from childhood into adult migraine with and without aura phenotype. There has been an evolution of our understanding of what was initially referred to as periodic symptoms of childhood and more recently been called childhood periodic syndromes and is now evolving into the terminology of episodic symptoms that are associated with migraine. International classification of headache disorders has been instrumental in the evolution of the classification of headache and children adults. The most recent classification utilizes and replaces the periodic symptom terminology with episodic symptoms that will no longer be limited to just childhood. This article will address the evolution of our understanding of the diagnostic criteria, pathophysiology and management of the episodic syndromes that may be associated with migraine.

Health-related quality of life in children and adolescents with cyclic vomiting syndrome: a comparison with published data on youth with irritable bowel syndrome and organic gastrointestinal disorders

OBJECTIVE

To evaluate health-related quality of life (HRQoL) in children with cyclic vomiting syndrome (CVS) and to compare child self-reports with those of their parents and with published reports of children with irritable bowel syndrome (IBS), children with organic gastrointestinal disorders, and a healthy control group.

STUDY DESIGN

Sixty-eight children aged 5-18 years with CVS confirmed in a gastroenterology clinic completed the Pediatric Quality of Life Inventory (PedsQL). Eighty-two parents completed the parent-proxy PedsQL for children aged 2-18 years. These results were compared with published data for children with IBS, organic gastrointestinal disorders, and a healthy control group using ANOVA. Intraclass correlation was used to evaluate concordance between child and parent reports of HRQoL.

RESULTS

HRQoL reported on the PedsQL by children with CVS was lower than that reported by children with IBS (P < .01) and healthy controls (P < .001), but did not differ from that reported by children with organic gastrointestinal disorders. Children with CVS also had lower HRQoL compared with healthy controls by parent-proxy report on the PedsQL (P < .001). Correlations between HRQoL reports by parents and children were moderate to good (intraclass correlation coefficients, 0.504-0.805; P < .01). Duration of CVS episodes, delay in CVS diagnosis, and number of school days missed due to CVS were associated with lower parent-rated HRQoL (P = .01).

CONCLUSION

Children with CVS reported lower HRQoL compared with those with IBS, and both parents and children reported lower HRQoL compared with healthy controls. Parent and child ratings of HRQoL converged. Improved recognition of CVS and school support might help mitigate the impact of CVS on HRQoL.

Autonomic epileptic seizures, autonomic effects of seizures, and SUDEP

Many generalized tonic-clonic seizures are accompanied by profound autonomic changes. However, autonomic seizures and autonomic status epilepticus can also be seen with specific electroclinical syndromes (Panayiotopoulos syndrome), etiologies, and localizations. Such autonomic symptoms may impact cardiorespiratory function. While it is likely that several factors contribute to SUDEP, further study of both ictal respiratory and cardiac changes and underlying neuroanatomical mechanisms involved in autonomic seizure semiology are likely to provide important data to improve our understanding of the pathophysiology of this devastating condition. This paper will review the association between autonomic symptoms and epileptic seizures and will highlight the work of three young investigators. Drs. Lisa Bateman and Brian Moseley will review their work on cardiorespiratory effects of recorded seizures and how this assists in our understanding of SUDEP. Dr. John Millichap will review autonomic seizures and autonomic dysfunctions related to childhood epilepsy and will discuss the importance of expanded research efforts in this field.

Cyclic vomiting syndrome developed after stroke

Cyclic vomiting syndrome is characterized by recurrent episodes of stereotyped vomiting separated by regular symptom-free periods. We describe a case of cyclic vomiting syndrome developed after stroke, which has not been reported to date. A 69-year-old woman experienced recurrent vomiting following left cerebral infarct. The patient's vomiting pattern was consistent with cyclic vomiting syndrome, and the diagnosis of cyclic vomiting syndrome was established by exclusion of other known disorders which could have resulted in vomiting. She was treated with imipramine hydrochloride and her symptom was well controlled.

Resolution of cyclic vomiting after appendectomy in a girl

Cyclic vomiting syndrome is a disorder characterized by recurrent, discrete, stereotypical episodes of nausea and vomiting. Although chronic or recurrent appendicitis may be a cause of recurrent abdominal pain, it rarely meets the diagnostic criteria for cyclic vomiting syndrome. Furthermore, mast cell counts are histologically high in chronic appendicitis. We report a 10-year-old Japanese girl with a cyclic pattern of vomiting that met the stringent diagnostic criteria for cyclic vomiting syndrome, and which was resolved after appendectomy. Histopathologic examination of the resected appendix showed not only acute mucosal inflammation but also chronic inflammatory changes. Because we speculated that recurrent or chronic appendicitis may have been related to the patient's vomiting bouts, we also immunohistochemically investigated the density of mast cells in the specimen. We found that the mast cell density was markedly high in the lamina propria of the appendix. In our patient, a type I hypersensitivity reaction with release of mediators by mast cells could have been the initial factor triggering the recurrent appendicitis, and this stressor could have initiated the vomiting cascade. In conclusion, chronic or recurrent appendicitis could be one of the causes of cyclic vomiting, and must be considered in the differential diagnosis of cyclic vomiting syndrome.

Review article: cyclic vomiting syndrome in adults--rediscovering and redefining an old entity

BACKGROUND

Cyclic vomiting syndrome is a disorder characterised by recurrent episodes of severe nausea and vomiting separated by symptom-free periods.

AIMS

To review the history, epidemiology, clinical aspects, pathophysiology, diagnosis and treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field.

METHODS

We conducted a PubMed search using such keywords as cyclic vomiting syndrome; nausea; vomiting; pathophysiology; diagnosis; treatment; trigger factors; gastric emptying test; autonomic nerve function test; gastrointestinal hormones; outcome and natural history and combined this information with the knowledge and extensive clinical research and publications from the authors.

RESULTS

Available data show that in adult cyclic vomiting syndrome, severe epigastric and sometimes diffuse abdominal pain accompanies most cycles of nausea and vomiting interspersed with periods of symptomatic remission. Psychological disorders, specifically anxiety and depression are common, and gastric emptying is actually rapid in approximately 60% of patients and normal in the remainder. There is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 15% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to co-existing psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use.

CONCLUSIONS

Cyclic vomiting syndrome in adults is an entity that is being increasingly recognised, but the need to educate Internists, Gastroenterologists and Emergency Department staff remains an ongoing challenge.

Nausea and vomiting

Nausea and vomiting are symptoms resulting from a triggered emetic reflex. Many endogenous and exogenous triggering factors can activate the emetic reflex, making understanding difficult and therapy challenging. The key to managing most cases of nausea and vomiting lies in a good history and a detailed physical examination. Most episodes of acute vomiting (lasting < 48 hours) have an evident triggering factor (eg, infection, viral illness, or food poisoning) and can be managed by removing the triggering agent and via supportive therapy. Chronic and unexplained nausea and vomiting can be a challenge. The cause is often obscure and requires special investigation. Functional gastroduodenal disorders such as cyclic vomiting syndrome, functional vomiting, and chronic idiopathic nausea should be considered if investigations are unrevealing. Knowledge regarding various emetic pathways and the specific neurotransmitters involved helps to target therapy. Histamine-1 receptor antagonists and muscarinic antagonists are suitable candidates for motion sickness and labyrinthine disorders. Phenothiazines, 5-hydroxytryptamine-3 receptor antagonists, corticosteroids, and benzodiazepines have a role in postchemotherapy and postoperative nausea and vomiting. Cannabinoid and neurokinin-1 receptor antagonists are best reserved for refractory cases of nausea and vomiting. Motilin agonists and metoclopramide are useful for treating impaired gastric motility disorders.

Breaking the cycle: cognitive behavioral therapy and biofeedback training in a case of cyclic vomiting syndrome

The present article presents a case of cognitive behavioral therapy (CBT) along with heart rate variability (HRV) biofeedback training for the treatment of a medication unresponsive 13-year-old boy with cyclic vomiting syndrome (CVS). CVS is characterized by recurring stereotypic episodes of vomiting, interspersed with asymptomatic periods. Triggers for vomiting include anticipatory anxiety related to school examinations, family conflicts, and birthday parties as well as infectious diseases, and certain foods. Current treatment design addressed two pivotal etiological factors: autonomic dysregulation and anticipatory anxiety. Treatment outcome suggests that vomiting episodes may be successfully prevented by aiding the patient to identify and manage precipitant psychological stressors, to regulate HRV patterns, and gain a renewed sense of bodily control and self-efficacy. Further research is suggested using a controlled study with pre- and post-behavioral and stress measures to evaluate the effectiveness of CBT and biofeedback training compared to pharmacotherapy and placebo.

Posterior reversible encephalopathy syndrome in a child with cyclical vomiting and hypertension: a case report

Introduction

Posterior reversible encephalopathy syndrome is characterized by headache, nausea and vomiting, seizures and visual disturbances. It has certain characteristic radiological features, which allow diagnosis in the appropriate clinical setting and enable appropriate clinical therapy to be instituted.

Case presentation

A 10-year-old Caucasian girl who was hospitalized due to recurrent vomiting was diagnosed as having posterior reversible encephalopathy syndrome after an initial diagnosis of cyclical vomiting and hypertension was made.

Conclusion

Posterior reversible encephalopathy syndrome is a rare disorder in children. Early recognition of characteristic radiological features is key to the diagnosis as clinical symptoms may be non-specific or mimic other neurological illnesses. To the best of our knowledge this is the first case to report an association between posterior reversible encephalopathy syndrome, cyclical vomiting and hypertension. Furthermore, in this case, the resolution of the abnormalities found on magnetic resonance imaging over time did not appear to equate with clinical recovery.

Autonomic nerve function in adults with cyclic vomiting syndrome: a prospective study

BACKGROUND

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder that is characterized by recurrent episodes of intense vomiting. There are several postulated mechanisms involved in its pathogenesis and one potential explanation for this disorder may be linked to autonomic dysfunction. The aim of our study was to evaluate autonomic nerve function in patients with CVS prospectively.

METHODS

We tested the sympathetic nervous system through postural changes in heart rate (HR) and blood pressure and the thermoregulatory sweat test. The parasympathetic nervous system was tested through the HR response to deep breathing (R-R variability on EKG).

KEY RESULTS

A total of 20 patients who met Rome III criteria for CVS, 14 (70%) women and 6 (30%) men, and 20 controls were enrolled in the study. A total of 17 (85%) CVS subjects and 2 (10%) controls had abnormalities on thermoregulatory sweat testing (P < 0.001). A total of 7 (35%) patients and one control subject had evidence of postural tachycardia (P = 0.04) with an increase in HR > 30 on standing. Of the subjects, 18 (90%) had either abnormal sudomotor function or postural tachycardia or both. The HR response to deep breathing was normal in 19 (95%) subjects with CVS and 18 (95%) controls.

CONCLUSIONS & INFERENCES

The results of this study suggest that the majority of subjects (90%) with CVS have impairment of the sympathetic nervous system with postural tachycardia and/or sudomotor dysfunction while parasympathetic nerve function appears to be intact. These findings of dysautonomia in CVS have implications in both the diagnosis and treatment of these patients.

Spectrum of gastric emptying patterns in adult patients with cyclic vomiting syndrome

BACKGROUND

Cyclic vomiting syndrome (CVS) in adults is a disorder characterized by recurrent and stereotypic episodes of severe nausea, vomiting and abdominal pain separated by symptom-free intervals. Both rapid and delayed gastric emptying (GE) have been observed but the reports involved small numbers of CVS patients.

METHODS

We performed a retrospective study of 92 adult patients who met Rome Ш diagnostic criteria for CVS between 2003 and 2009 at the Kansas University Medical Center. Gastric emptying was measured by a standardized scintigraphic method involving a low fat (2%) isotope labeled egg white meal of 250 Kcal, with anterior and posterior gastric imaging in the standing position obtained at 0, 1, 2, 4 h after meal ingestion. Rapid GE was defined as <50% isotope retention at 1st h and/or <30% at 2nd h and delayed GE as >10% at 4 h.

KEY RESULTS

Ninety two patients were analyzed: 47 males and 45 females mean of age 37 ± 12 years (range: 20-68 years). There were 27 patients with a personal history of migraine headache, 30 with history of marijuana use, 12 had diabetes mellitus (DM) and 10 had irritable bowel syndrome (IBS) as an accompanying diagnosis. Fifty four patients (59%) met criteria for rapid GE, 25 (27%) had normal GE and 13 (14%) had slow GE. Eighty percent of patients with co-existing IBS symptoms were identified as rapid. The subset with delayed emptying was often associated with narcotics use, DM and marijuana use (P < 0.05).

CONCLUSIONS & INFERENCES

(i) In adult CVS patients, GE is generally either rapid or normal. (ii) Cyclic vomiting syndrome is an important new etiology to explain the finding of rapid GE on a radionuclide test. (iii) The small subset of CVS patients (14%) whose GE was slow were explained by the role of narcotics and/or marijuana.