Applying Nutrient Drink Test in Understanding Pathophysiology of Cyclic Vomiting Syndrome

Up to 14% of unexplained vomiting in adults is attributed to an under recognized and often misdiagnosed disorder termed cyclic vomiting syndrome (CVS). As CVS is better understood, gastroenterologists are increasingly recognizing the importance of timely diagnosis and early management for this chronic and debilitating disorder. Currently, the only gold standard diagnostic strategy involves evaluating clinical criteria set by the Rome Foundation, such as vomiting frequency and duration of episodes. Outside of these subjective criteria, no definitive and objective diagnostic strategy for cyclic vomiting syndrome exists.

Developing diagnostic strategies has been difficult given the exact etiology of CVS is still unknown. One physiologic theory includes rapid gastric emptying (GE)-or a dumping-like syndrome related to impaired gastric accommodation. A retrospective analysis observed rapid gastric emptying by standard 4-hour scintigraphic gastric emptying study in 80% of subjects, suggesting a relationship with CVS and rapid GE. In turn, rapid emptying has been hypothesized to relate with abnormal gastric accommodation - the reflex allowing storage of food through increased fundic volume. This physiologic abnormality can be readily and easily measured using non-invasive tools, but have never been tested in CVS. To explore this further, we aim to determine if CVS patients have abnormal gastric accommodation measured by nutrient drink test.