OBJECTIVES

Cyclic vomiting syndrome (CVS) remains a diagnostic challenge due to its nonspecific presentation despite consensus-based diagnostic criteria. There is a need for improved, evidence-based diagnostic criteria. We hypothesized that symptoms differ quantitatively between children with CVS versus other vomiting conditions and that current diagnostic criteria are not sufficiently sensitive for diagnosing CVS.

METHODS

Observational, prospective study of children ages 3-18 years with unexplained vomiting episodes evaluated in the outpatient gastroenterology clinic, emergency department, and inpatient units at Children's Wisconsin. Parents completed symptom surveys at 0, 3, and 6 months. Diagnostic workup and treatment response were monitored by chart review. A final diagnosis (CVS vs. non-CVS) was assigned for group comparisons and receiver operating characteristics (ROC) analysis of diagnostic cutoffs.

RESULTS

Of 108 subjects enrolled, 46 CVS and 54 non-CVS patients were analyzed. The groups reported overall different episode frequencies with more CVS versus non-CVS (81% vs. 55%) having ≥4 episodes/preceding 12 months (p = 0.013). CVS patients also had longer vomiting episodes (p = 0.03). To distinguish CVS from non-CVS, ROC analyses demonstrated the highest sensitivity for a frequency of 4-10 episodes/12 months (p = 0.002) and a duration threshold of >2 h (p < 0.001). CVS patients reported specific episode characteristics: photophobia (p = 0.003), diaphoresis (p = 0.002), multiple emeses/hour (p = 0.001), stereotypical episodes (p = 0.008), and continued retching after gastric emptying (p = 0.008). Less than half of CVS patients met Rome IV and North American Society for Pediatric Gastroenterology, Hepatology & Nutrition diagnostic criteria.

CONCLUSIONS

Children with CVS display a distinctive vomiting pattern and clinical features compared to other vomiting conditions. Our findings will help improve current diagnostic criteria.