Cyclic Vomiting Syndrome in Children

Recent advances in understanding the neurobiology of pediatric functional neurological disorder

INTRODUCTION

Functional neurological disorder (FND) is a neuropsychiatric disorder that manifests in a broad array of functional motor, sensory, or cognitive symptoms, which arise from complex interactions between brain, mind, body, and context. Children with FND make up 10%-20% of presentations to neurology services in children's hospitals and up to 20% of adolescents admitted to hospital for the management of intractable seizures.

AREAS COVERED

The current review focuses on the neurobiology of pediatric FND. The authors present an overview of the small but growing body of research pertaining to the biological, emotion-processing, cognitive, mental health, physical health, and social system levels.

EXPERT OPINION

Emerging research suggests that pediatric FND is underpinned by aberrant changes within and between neuron-glial (brain) networks, with a variety of factors - on multiple system levels - contributing to brain network changes. In pediatric practice, adverse childhood experiences (ACEs) are commonly reported, and activation or dysregulation of stress-system components is a frequent finding. Our growing understanding of the neurobiology of pediatric FND has yielded important flow-on effects for assessing and diagnosing FND, for developing targeted treatment interventions, and for improving the treatment outcomes of children and adolescents with FND.

Good response to rectal diazepam in refractory cases of cyclic vomiting: A case-series and review of the literature

Key Clinical Message

Although increasing in number, cases of CVS are being frequently misdiagnosed and many are refractory to the available treatments. This paper draws attention to a timely consideration of this disorder upon suspicion and proposes rectal diazepam and cinnarizine as highly effective treatments in refractory cases of CVS.

Abstract

Cyclic vomiting syndrome (CVS) is a set of recurrent episodic attacks of nausea and vomiting. This is a migraine-related disorder that mostly affects children. Several medications have been recommended for abortive and prophylactic treatment. Unfortunately, in some cases, the treatment is not completely effective and affects the quality of life of the sufferer. In this paper, we report on two cases of children experiencing refractory CVS attacks who were not responsive to recommended medications for acute phase and prophylaxis. This account highlights the efficacy of rectal diazepam for the acute phase of CVS and cinnarizine, an anti-migraine and anti-histamine agent, for prophylaxis of further attacks.

Sudden onset headaches in paediatric emergency departments: diagnosis and management

Headache is one of the most common pain syndromes in the paediatric population. Headaches are classified as primary (migraine, tension-type headaches, trigeminal autonomic cephalalgia and other primary headaches) or secondary (e.g. post-traumatic). Non-febrile, non-traumatic headaches represent 1% of all paediatric emergency departments (PED) visits. Many patients present with an acute, moderate to severe pain, sometimes with a sudden onset. Sudden onset headache can be the main symptom of life-threatening neurological conditions as well as a sign of primary headaches such as thunderclap or stabbing headaches. This review aims to describe the presentation of sudden primary headaches in children, in order to help the physician to provide effective management in the emergency setting.

Association of Anxiety and Gastrointestinal Comorbidities in Repeat Hospital Admissions in Pediatric Cyclic Vomiting Syndrome

INTRODUCTION

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder with recurrent episodes of intense nausea and vomiting and thus may require frequent hospitalizations. There is paucity of data exploring the association of psychiatric and gastrointestinal comorbidities in repeat hospitalizations among pediatric patients with CVS.

METHODS

We analyzed the Pediatric Health Information System database and included all patients up to 18 years of age with a diagnosis of CVS between 2016 and 2020. We excluded patients with chronic conditions, which mimic CVS. The primary outcome variable was 90-day admission rate, which was defined as a visit to emergency department or admission to observation/inpatient unit with a primary diagnosis of CVS within 90 days after an index CVS hospitalization.

RESULTS

We evaluated a total of 2,604 hospitalizations represented by 1,370 unique individuals. The overall 90-day admission rate was 28.5%, which steadily decreased from 35.7% in 2016 to 23% in 2019 ( P < 0.001). Patients in the repeat hospitalization cohort were slightly older and more often men. Patients with repeat admissions had an increased proportion of anxiety and other gastrointestinal disorders. Multivariable logistic regression showed that anxiety, gastroesophageal reflux disease, functional dyspepsia, and abdominal migraine were associated with increased odds of repeat admissions.

DISCUSSION

Ninety-day admission rates in pediatric CVS are decreasing overall, although still contributing to significant healthcare expenditure. Anxiety and gastrointestinal comorbidities were associated with increased risk of repeat admissions. Further prospective studies are needed to better understand the complex interactions of these comorbidities and their management affecting the natural course of CVS.

Whole exome/genome sequencing in cyclic vomiting syndrome reveals multiple candidate genes, suggesting a model of elevated intracellular cations and mitochondrial dysfunction

Objective

To utilize whole exome or genome sequencing and the scientific literature for identifying candidate genes for cyclic vomiting syndrome (CVS), an idiopathic migraine variant with paroxysmal nausea and vomiting.

Methods

A retrospective chart review of 80 unrelated participants, ascertained by a quaternary care CVS specialist, was conducted. Genes associated with paroxysmal symptoms were identified querying the literature for genes associated with dominant cases of intermittent vomiting or both discomfort and disability; among which the raw genetic sequence was reviewed. "Qualifying" variants were defined as coding, rare, and conserved. Additionally, "Key Qualifying" variants were Pathogenic/Likely Pathogenic, or "Clinical" based upon the presence of a corresponding diagnosis. Candidate association to CVS was based on a point system.

Results

Thirty-five paroxysmal genes were identified per the literature review. Among these, 12 genes were scored as "Highly likely" (SCN4A, CACNA1A, CACNA1S, RYR2, TRAP1, MEFV) or "Likely" (SCN9A, TNFRSF1A, POLG, SCN10A, POGZ, TRPA1) CVS related. Nine additional genes (OTC, ATP1A3, ATP1A2, GFAP, SLC2A1, TUBB3, PPM1D, CHAMP1, HMBS) had sufficient evidence in the literature but not from our study participants. Candidate status for mitochondrial DNA was confirmed by the literature and our study data. Among the above-listed 22 CVS candidate genes, a Key Qualifying variant was identified in 31/80 (34%), and any Qualifying variant was present in 61/80 (76%) of participants. These findings were highly statistically significant (p < 0.0001, p = 0.004, respectively) compared to an alternative hypothesis/control group regarding brain neurotransmitter receptor genes. Additional, post-analyses, less-intensive review of all genes (exome) outside our paroxysmal genes identified 13 additional genes as "Possibly" CVS related.

Conclusion

All 22 CVS candidate genes are associated with either cation transport or energy metabolism (14 directly, 8 indirectly). Our findings suggest a cellular model in which aberrant ion gradients lead to mitochondrial dysfunction, or vice versa, in a pathogenic vicious cycle of cellular hyperexcitability. Among the non-paroxysmal genes identified, 5 are known causes of peripheral neuropathy. Our model is consistent with multiple current hypotheses of CVS.

[Clinical and gastroscopic features of children with cyclic vomiting syndrome: an analysis of 63 cases]

OBJECTIVES

To study the clinical and gastroscopic features of children with cyclic vomiting syndrome.

METHODS

A retrospective analysis was performed on the medical data of 63 children with cyclic vomiting syndrome who were hospitalized and followed up in Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University from August 2019 to March 2022.

RESULTS

Among the 63 children, there were 30 boys and 33 girls, with a mean age of 6.11 years, a mean course of disease of 2.57 years, and a mean vomiting period of 4.04 days. The most common accompanying symptom was listlessness or somnolence (55/63, 87%), followed by anorexia (45/63, 71%), abdominal pain or abdominal discomfort (40/63, 63%), constipation (19/63, 30%), salivation (12/63, 19%), nausea (11/63, 17%), headache (11/63, 17%), fever (6/63, 10%), and rash (1/63, 2%). All 63 children underwent gastroscopy, among whom 3 had no marked abnormalities, 22 (35%) had chronic superficial gastritis or chronic non-atrophic gastritis alone, and 38 (60%) had other abnormal changes aside from chronic gastritis (16 children with reflux esophagitis, 12 with bile reflux gastritis, 13 with duodenitis, 10 with erosive gastritis, and 5 with gastric or duodenal ulcer). Among the 63 children, 42 underwent pathological examinations of gastric mucosa, among whom 5 had no marked abnormalities, 34 had mild chronic gastritis, 2 had moderate chronic gastritis, and 1 had severe chronic gastritis. Among the 63 children, 15 received 24-hour dynamic esophageal pH monitoring during the interictal period, among whom 9 children were found to have pathological acid reflux.

CONCLUSIONS

In addition to recurrent vomiting, most children with cyclic vomiting syndrome also have the symptoms such as somnolence or listlessness, anorexia, and abdominal pain. The main manifestation on gastroscopy is chronic gastritis, and most children may also have reflux esophagitis, bile reflux gastritis, and erosive gastritis. Mild chronic gastritis is the main pathological change of gastric mucosa.

Cyclic vomiting syndrome in children: a nationwide survey of current practice on behalf of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP)

Background

Cyclic Vomiting Syndrome (CVS) is a rare functional gastrointestinal disorder, which has a considerable burden on quality of life of both children and their family. Aim of the study was to evaluate the diagnostic modalities and therapeutic approach to CVS among Italian tertiary care centers and the differences according to subspecialties, as well as to explore whether potential predictive factors associated with either a poor outcome or a response to a specific treatment.

Methods

Cross-sectional multicenter web-based survey involving members of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP).

Results

A total of 67 responses were received and analyzed. Most of the respondent units cared for less than 20 patients. More than half of the patients were referred after 3 to 5 episodes, and a quarter after 5 attacks. We report different diagnostic approaches among Italian clinicians, which was particularly evident when comparing gastroenterologists and neurologists. Moreover, our survey demonstrated a predilection of certain drugs during emetic phase according to specific clinic, which reflects the cultural background of physicians.

Conclusion

In conclusion, our survey highlights poor consensus amongst clinicians in our country in the diagnosis and the management of children with CVS, raising the need for a national consensus guideline in order to standardize the practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13052-022-01346-y.

Adult acetonemic vomiting complicated with low body weight in a subject with Mycobacterium avium complex pulmonary disease: a case report

Pulmonary diseases often cause significant health issues and nutritional disorders. Weight loss and malnutrition are related to the severity of obstructive disorders. Therefore, patients with such conditions often experience low nutritional energy. Acetonemic vomiting is caused by acetonemic syndrome. Previously, it was believe that acetonemic vomiting was observed only in childhood. However, it was recently suggested that acetonemic vomiting can also occur in adults. It is also considered that acetonemic vomiting can occur in subjects with low body weight because stored carbohydrate levels are reduced and fats are mainly used for energy. Consequently, large amounts of acetone are produced, ultimately resulting in nausea and vomiting. In this study, we report a case of adult acetonemic vomiting complicated by low body weight in a subject with Mycobacterium avium complex pulmonary disease.

Differential Diagnosis of Cyclic Vomiting and Periodic Headaches in a Child with Ventriculoperitoneal Shunt: Case Report of Chronic Shunt Overdrainage

Fourteen months after the implantation of a ventriculoperitoneal shunt catheter, a six-year-old boy developed recurrent, severe headaches and vomiting every three weeks. The attacks were of such severity that hospitalizations for analgesic and antiemetic therapies and intravenous rehydration and electrolyte substitution were repeatedly required. The patient was asymptomatic between the attacks. After an extensive diagnostic workup-including repeated magnetic resonance imaging (MRI) and neurosurgical examinations-common differential diagnoses, including shunt overdrainage, were ruled out. The patient was transferred to a specialized pediatric pain clinic with suspected cyclic vomiting syndrome (CVS). Despite intensive and in part experimental prophylactic and abortive pharmacological treatment, there was no improvement in his symptoms. Consecutive MRI studies reinvestigating the initially excluded shunt overdrainage indicated an overdrainage syndrome. Subsequently, the symptoms disappeared after disconnecting the shunt catheter. This case report shows that even if a patient meets CVS case definitions, other differential diagnoses must be carefully reconsidered to avoid fixation error.

Clinical features and long-term outcomes in pediatric cyclic vomiting syndrome: A 9-year experience at three tertiary academic centers

BACKGROUND

Pediatric cyclic vomiting syndrome (CVS) is a little-known clinical condition, frequently diagnosed with delay. This study aims to describe the clinical presentation and management and to define possible predictive factors of the disease outcome.

METHODS

In this retrospective study, all children who were diagnosed with CVS during the period 2010-2019 in three tertiary academic centers were included. The association between clinical variables and outcomes was investigated.

KEY RESULTS

Fifty-seven children were included (male/female ratio 1.3:1; mean age at diagnosis 8.2 years). At the time of diagnosis, 63% of children had at least one episode every month. One or more prodromes were reported by 75% of patients. Family history of migraine was reported for 47% of children. Nearly, all of the children were started on prophylactic treatment. The median follow-up period was 29 months ± 15. Overall, 56% of children had resolution of vomiting. Twenty-six percent of children developed migraine. There were no differences in gender, age at onset, duration of follow-up, severity, medication, family history, or trigger factors between children who underwent resolution of vomiting and those who did not, or between children who suffered from migraine or not at follow-up. Four types of disease outcome were recognized, that is, resolution of vomiting with or without associated symptoms; persistence of vomiting with or without associated symptoms.

CONCLUSIONS AND INFERENCES

Cyclic vomiting syndrome clinical presentation has inter-individual variability. Most children recover at follow-up, but often develop further somatic symptoms. In this study, no clinical variable clearly predicted the evolution of the syndrome toward one or the other outcome.

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.

Migraine and Its Equivalents: What Do They Share? A Narrative Review on Common Pathophysiological Patterns

Migraine is the first in order of frequency of the neurological disorders, affecting both adult and paediatric populations. It is also the first cause of primary headaches in children. Migraine equivalents are periodic disorders that can be associated with migraine or considered as prognostic features of a future migraine manifestation. Despite the mechanisms underlying migraine and its equivalents are not entirely clear, several elements support the hypothesis of common pathophysiological patterns shared by these conditions. The aim of this review is thus to analyze the literature in order to highlight which currently known mechanisms may be common between migraine and its equivalents.

Cyclic vomiting syndrome in children

QUESTION

Several children in my office have recurrent vomiting events and they usually end up in the emergency department for intravenous rehydration. One of them has been suffering from those attacks approximately once per month for the past 2 years, leading to a reduction in her quality of life. What is known about cyclic vomiting syndrome and can it be prevented?

ANSWER

Cyclic vomiting syndrome includes severe episodic vomiting lasting for hours or days, separated by symptom-free intervals. This gut-brain interaction is poorly understood and is difficult to diagnose. Children suffer from relentless vomiting, lethargy, abdominal pain, anorexia, and nausea. Half of the children require intravenous rehydration. Once diagnosis is made, supportive measures to reduce suffering are recommended and include administering fluids, encouraging sleep, promoting quiet environments, and administering antiemetics or sedatives. In adults, tricyclic antidepressants such as amitriptyline, as well as topiramate as second-line therapy, have been proposed for prophylactic treatment. However, pediatric data are very limited and evidence does not support any recommended course of prophylactic therapy for children with the condition.

[Not Available]

Question

Plusieurs enfants de ma clinique ont des épisodes récurrents de vomissements, et ils se retrouvent habituellement au service d’urgence pour une réhydratation par intraveineuse. L’un d’entre eux souffre de l’une de ces attaques environ 1 fois par mois depuis les 2 dernières années, ce qui nuit à sa qualité de vie. Que sait-on du syndrome des vomissements cycliques, et peut-on le prévenir ?

Réponse

Le syndrome des vomissements cycliques désigne des vomissements épisodiques sévères qui durent des heures, voire des jours, entrecoupés d’intervalles sans symptômes. Cette interaction entre l’appareil digestif et le cerveau est mal comprise et difficile à diagnostiquer. Les enfants souffrent de vomissements incessants, de léthargie, de douleur abdominale, d’anorexie et de nausée. Chez la moitié de ces enfants, il faut une réhydratation par intraveineuse. Une fois le diagnostic posé, des mesures de soutien pour réduire la souffrance sont recommandées, y compris l’administration de liquides, la favorisation du sommeil, la promotion d’environnements calmes et l’administration d’antiémétiques ou de sédatifs. Chez les adultes, des antidépresseurs tricycliques comme l’amitriptyline, de même que le topiramate comme thérapie de deuxième intention, ont été proposés comme prophylaxie. Par ailleurs, les données pédiatriques sont très limitées, et les données probantes ne corroborent aucune thérapie prophylactique recommandée pour les enfants souffrant de cette affection.

The childhood migraine syndrome

Migraine is a complex genetic brain disorder with an intricate pathogenesis and polymorphous clinical presentations, particularly in children. In this Perspective, we describe the different phenotypes of migraine in children, including conditions that have been referred to in the International Classification of Headache Disorders as "syndromes that may be related to migraine''. Evidence is presented for the integration of abdominal migraine, cyclical vomiting syndrome, benign paroxysmal vertigo, benign paroxysmal torticollis and infantile colic into the unified diagnosis of 'childhood migraine syndrome' on the basis of clinical and epidemiological characteristics, and shared inheritance. In our opinion, such integration will guide clinicians from specialities other than neurology to consider migraine in the assessment of children with these disorders, as well as stimulate research into the genetics, pathophysiology and clinical features of all disorders within the syndrome. A diagnosis of childhood migraine syndrome would also enable patients to benefit from inclusion in clinical trials of old and new migraine treatments, thus potentially increasing the number of treatment options available.

Highly effective use of aprepitant in an adolescent girl with severe cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is a debilitating functional gastrointestinal disorder. Diagnosis is based on the Rome III criteria. There are no evidence-based guidelines for the management of paediatric CVS, although ondansetron and antimigraine medications are frequently tried. We describe a 13-year-old adolescent girl with severe CVS and numerous hospital admissions for dehydration because of cyclic vomiting. She had failed oral ondansetron therapy. Oral aprepitant (125 mg in the first, and 85 mg on the second and third days), a neurokinin 1 receptor antagonist that has been approved for preventing chemotherapy-induced vomiting or postoperative emesis, was tried in our patient at home during the first prodromal signs of an upset stomach. She had a dramatic response to it, with no further episodes of vomiting since its start. There is an urgent need for randomised clinical studies to assess the efficacy of available treatment options, including aprepitant in patients with severe CVS.

Cyclic vomiting syndrome: A narrative review and guide to management

OBJECTIVES/BACKGROUND

Cyclic vomiting syndrome (CVS) is a disabling disorder of gut-brain interaction manifested by stereotypical and severe episodes of nausea and vomiting. Prevalence data indicate that CVS affects 1-2% of children and there has been a recent dramatic rise in diagnosed adults.

METHODS

This narrative review summarizes relevant literature pertaining to pediatric and adult CVS and provides a guide to management based on extensive clinical experience.

RESULTS

More timely diagnosis is facilitated by an expert consensus diagnostic approach and limited testing. Some diagnostic tests of exclusion remain essential. These include an upper gastrointestinal (GI) contrast study to exclude intestinal malrotation and basic laboratory screening. An abdominal ultrasound is recommended to exclude renal hydronephrosis in children and biliary disease in adults. Exclusion of metabolic/genetic conditions is warranted in those with specific warning signs, presentation in infants/toddler age, and in those with refractory disease. In the absence of chronic GI symptoms, referral to a GI specialist for upper endoscopy is generally not necessary in children but recommended in adults. A large subset termed migraine-equivalent CVS display strong clinical and genetic features of migraine. A unifying pathophysiologic core concept involves neuronal hyperexcitability and aberrant central modulation of autonomic signals. This is coupled with multiple susceptibility factors including mitochondrial dysfunction/cellular energy deficits, a hyper-responsive hypothalamic-pituitary-adrenal axis and many comorbidities that increase vulnerability to triggering events. CVS episodes are frequently triggered by stressors and intercurrent illnesses. Lifestyle and non-pharmacological interventions thus play a pivotal role in successful management. Pharmacological therapies are categorized into abortive, supportive/rescue, and prophylactic treatments. The majority respond particularly well to migraine-focused treatment strategies.

CONCLUSION

Despite improved characterization and understanding, CVS remains classified as a functional disorder of brain-gut interaction that is often disjointly managed by generalists and subspecialists. Early recognition, evaluation, and management will facilitate care and improve outcomes. Further research into its natural history with common progression to migraine headaches, neuroendocrine mechanisms, and the pathophysiologic relation to migraine diathesis is much needed.