Basics
Description
- Cyclic vomiting syndrome (CVS) is an idiopathic disorder characterized by recurrent, stereotypical episodes of vomiting with intervening periods of normal health.
- Essential clinical features of CVS are 3 or more discrete episodes of vomiting; intervals of completely normal health between episodes; stereotypical episodes with regard to timing of onset, symptoms, and duration; as well as the absence of an identifiable organic cause for vomiting.
Epidemiology
- CVS commonly starts in early childhood.
- Prevalence of 1.9-2.3% has been reported.
- The syndrome is more common in Caucasians.
Commonly Associated Conditions
- 2/3 of CVS patients have symptoms of IBS.
- 11% of CVS patients have migraine headaches and a third of patients later develop migraine headaches.
Diagnosis
- A consensus statement by the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) expert task force suggests the diagnosis can be made if the following criteria are met:
- A minimum of 3 attacks during a 6-month period or at least 5 attacks in any interval
- Episodic attacks of intense nausea and vomiting lasting 1 hour to 10 days and occurring at least 1 week apart
- Stereotypical pattern and symptoms in the individual patient
- Vomiting during attacks occurs at least 4 times/h for at least 1 hour.
- Return to baseline health between episodes
- Not attributed to another disorder
- If the above criteria is met, the diagnosis should be considered most likely to be CVS and the workup should consist of the following tests only:
- Electrolytes, glucose, BUN, and creatinine
- A UGI series to evaluate for malrotation
- Red flags that CVS is not the correct diagnosis include the following:
- Episode of vomiting is characterized by the presence of the following:
- Bilious emesis
- Severe abdominal pain or tenderness
- Hematemesis
- If episodes are triggered by intercurrent illness, fasting, or high-protein meal, the following labs should be obtained at the beginning of the attack prior to IV fluid:
- Glucose, electrolytes for anion gap, urine ketones serum lactate, ammonia and amino acids, urine organic acids. Optional metabolic labs include plasma carnitine and acylcarnitine.
- If episodes occur in the context of an abnormal neurologic exam including severe altered mental status, papilledema, abnormal eye movements, motor asymmetry, and gait abnormality, consultation with a neurologist is indicated and a brain MRI should be obtained.
- Consider at any given time:
- US of abdomen and pelvis
- UGI series
- Amylase and lipase
- Esophagogastroduodenoscopy
- During an attack, obtain LFTs, lipase ± amylase.
History
- Children with CVS experience a stereotypical pattern of vomiting characterized by a consistent time of onset, duration, and associated symptoms.
- Vomiting frequency is high, with median of 6 bouts of emesis per hour, often bilious and associated with severe nausea.
- The intense vomiting results in dehydration and need for IV hydration.
- Accompanying symptoms include nausea, retching, headache, abdominal pain, pallor, listlessness, anorexia, and photophobia.
- Physical and psychological stresses are common triggers.
- CVS episodes are most likely to start in the early morning hours.
Physical Exam
Physical exam is often consistent with dehydration, and young children may appear listless.
Diagnostic Tests & Interpretation
The consideration of established criteria is important when diagnosing CVS, as is a thorough workup to rule out other etiologies that may explain the symptoms. These tests may include blood, urine, and imaging studies depending on the history and physical exam of the individual child.
Lab
- Basic metabolic panel: Na+, K+, Cl-, HCO3, glucose, BUN, and creatinine
- Liver and pancreas: ALT, GGT, lipase ± amylase
- Other: urine ketones, lactate, ammonia, serum amino acids, urine organic acids, plasma carnitine, and acylcarnitine
Imaging
- UGI series
- A UGI should be performed in all patients who present with bilious emesis and who are suspected to have CVS.
- Abdominal US
- Helpful in evaluation of the hepatobiliary and urinary systems
- Brain MRI
- Should be obtained when episodes of emesis are associated with progressive or acute, as well as diffuse or focal, neurologic symptoms or signs
- MRI, rather than CT or skull x-ray is the preferred modality for visualization of the posterior fossa.
Diagnostic Procedures/Other
Esophagogastroduodenoscopy
- May be indicated if hematemesis occurs following multiple episodes of emesis in a patient with CVS
- Most likely etiologies of hematemesis in a child with CVS are mild esophagitis, Mallory-Weiss tear, or prolapse gastropathy.
- Endoscopy may also be indicated if patients have persistent symptoms between episodes suggestive of peptic/bacterial, allergic, inflammatory or celiac disease, or hematemesis of large quantity that may require endoscopic hemostasis.
Differential Diagnosis
- Malrotation
- UPJ obstruction
- Rumination syndrome
- Gastroparesis
- Pseudoobstruction
- CNS lesion
- Increased intracranial pressure
- Infectious illness
- Pancreatitis
- Mitochondrial disorder
- Cannabinoid hyperemesis syndrome
Treatment
- The treatment strategy should be tailored to an individual taking into account the following:
- The frequency and severity of attacks as well as how badly it impacts the patient
- Potential side effects of the treatment have to also be taken into consideration.
- Treatment of children with CVS can be as follows:
- Prophylactic or preventive measures
- Abortive and supportive interventions
General Measures
There are a number of lifestyle changes that can be implemented that may prevent recurrence of CVS attacks without resorting to daily medications. Targeted lifestyle changes that can be effective are best found by reviewing a detailed vomiting diary to identify triggers for episodes. Generally speaking, the following are effective measures:
- Reassurance and education of patients and their families about CVS to decrease stress
- Avoidance of triggers and precipitating factors, including prolonged fasting, poor sleep hygiene, chocolate, cheese, monosodium glutamate, antigenic foods, and excessive exercise
- If episodes are induced by fasting, the child should have supplemental carbohydrate by having snacks between meals, before exertion, or at bedtime.
- Considering CVS to be in the migraine spectrum, migraine headache lifestyle interventions by doing regular aerobic exercise, regular meal times, and regulated consumption of caffeine
Medication
- Children >5 years of age
- Amitriptyline, a tricyclic antidepressant (TCA), has been shown to be very effective.
- It is recommended to initially prescribe a dose of 0.25-0.5 mg/kg PO at bed time.
- Doses should be increased by 5-10 mg weekly to a maximum dose of 1-1.5 mg/kg if symptoms continue to occur.
- Patients should be evaluated prior to starting amitriptyline with an EKG for QTc abnormality and 10 days after achieving peak dose.
- Side effects of this drug consist of arrhythmia (prolongation of the QT interval), sedation, behavioral changes, and constipation.
- Nortriptyline is another TCA that can be used as an alternative.
- Propranolol, a β-blocker, is considered a 2nd-line therapy.
- This should be dosed at 0.25-1 mg/kg/day PO, with a typical maximum dose of 10 mg b.i.d. or t.i.d.
- Heart rate should be monitored and maintained ≥60 bpm.
- Side effects include lethargy and reduced exercise intolerance.
- Propranolol is contraindicated in children with asthma, diabetes, heart disease, and depression. Propranolol must be tapered for 1-2 weeks when it is discontinued.
- Children 5 years of age or younger can be treated by the following:
- Cyproheptadine, which is an antihistamine, is first choice.
- Dosed at 0.25-0.5 mg/kg/day PO divided b.i.d. or t.i.d., the β-blocker propranolol can be used as a second choice as discussed above.
- Nutritional supplements including the following:
- L-carnitine 50-100 mg/kg/day PO divided b.i.d. or t.i.d. (Side effects reported include diarrhea and fishy body odor.)
- Coenzyme Q10 10 mg/kg/day PO divided b.i.d. or t.i.d. (max 100 mg t.i.d.)
- Other medications and supplements that have been used in treating CVS in a prophylactic measure include the following and are generally only prescribed by neurologists: phenobarbital or alternative anticonvulsants; topiramate, valproic acid, gabapentin, levetiracetam.
- A plan that combines lifestyle changes and medications with careful attention to dosing, side effects, and specialist referrals should be put in place and clearly communicated with the patients and parents.
Additional Therapies
When children with CVS have an acute episode, they will require both supportive and abortive interventions.
- Decreasing stimulation by situating the patient in a quiet and dark area
- Providing fluid replacements with electrolytes and calories along with antiemetics and analgesics
- Identifying possible metabolic decompensation by paying attention to the following:
- Anion gap, lactic acidosis, and hyperglycemia
- Using fluids with higher dextrose concentration such as 10% may also be very helpful.
- Abortive intervention
- Sumatriptan, an antimigraine drug, can be given at the time of onset at a dose of 20 mg intranasally.
- Possible side effects: neck pain or burning and coronary vasospasm
- A contraindication for its use is comorbidity with basilar artery migraines.
- Supportive care
- Fluids: D10 1/2 NS with or without KCl at 1 1/2 times maintenance
- Peripheral parenteral nutrition may be necessary if the patient had no enteral intake for 3-5 days.
- Antiemetic
- Ondansetron at a dose of 0.15 mg/kg/dose (max dose: 16 mg) IV given every 4-6 hours
- Sedatives
- Diphenhydramine 1-1.25 mg/kg/dose (max dose: 50 mg) IV every 6 hours
- Lorazepam 0.05-0.1 mg/kg/dose (max dose: 2 mg) IV every 6 hours
- Analgesics
- Ketorolac 0.4-1 mg/kg IV every 6 hours with a max dose of 30 mg and total daily max of 120 mg. Do not exceed 3-5 days of continuous use.
- It is also important to treat any abdominal pain, diarrhea, hypertension, and complications that may result from the persistent emesis such as dehydration, weight loss, hematemesis, metabolic acidosis, and syndrome of inappropriate antidiuretic syndrome (SIADH).
- Once the episode of emesis is over, the child can be fed ad libitum.
Follow-up Recommendations
Referral to either pediatric gastroenterologists or neurologists with special interest in CVS should be made.
Additional Reading
- Boles RG. High degree of efficacy in the treatment of cyclic vomiting syndrome with combined co-enzyme Q10, L-carnitine and amitriptyline, a case series. BMC Neurol. 2011;11:102. [View Abstract]
- Fleisher DR, Matar M. The cyclic vomiting syndrome: a report of 71 cases and literature review. J Pediatr Gastroenterol Nutr. 1993;17(4):361-369. [View Abstract]
- Li BU, Lefevre F, Chelimsky GG, et al. North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition consensus statement on the diagnosis and management of cyclic vomiting syndrome. J Pediatr Gastroenterol Nutr. 2008;47(3):379-393. [View Abstract]
- Li BU, Murray RD, Heitlinger LA, et al. Heterogeneity of diagnoses presenting as cyclic vomiting. Pediatrics. 1998;102(3, Pt 1):583-587. [View Abstract]
- Robinson TL, Cheng FK, Domingo CA, et al. Spicing up the differential for cyclical vomiting. Am J Gastroenterol. 2013;108(8):1371. [View Abstract]
Patient Teaching
Patients and parents should be directed to visit the following:
- The Cyclic Vomiting Syndrome Association Web site: http://www.cvsaonline.org
- International Foundation for Functional Gastrointestinal Disorders (IFFGD) Web site: http://www.aboutkidsgi.org/site/about-gi-health-in-kids/functional-gi-and-motility-disorders/cyclic-vomiting-syndrome
Codes
ICD09
- 536.2 Persistent vomiting
ICD10
- G43.A0 Cyclical vomiting, not intractable
- G43.A1 Cyclical vomiting, intractable
SNOMED
- 18773000 cyclical vomiting syndrome (disorder)
FAQ
- Q: How should I evaluate a child with presumed CVS who presents with progressive or focal neurologic findings?
- A: The child should be evaluated for increased intracranial pressure, as well as a metabolic disorder.
- Q: How can one distinguish true encephalopathy from CVS-associated listlessness in child presenting to the ED?
- A: The child with CVS will respond to commands appropriately and is oriented despite the desire to remain low key due to the severe nausea. In contrast, a child with metabolic encephalopathy is most likely to be confused, disoriented, and difficult to arouse.