Cyclic vomiting syndrome, or cyclical vomiting syndrome, (CVS) is a chronic functional condition of unknown cause characterized by recurring attacks of intense nausea, vomiting, and sometimes abdominal pain, headaches, or migraines and prostration with no apparent cause. CVS typically develops during childhood but it may persist into adult life. Vomiting occurs at frequent intervals for hours or days. The episodes tend to be similar to each other in symptoms and duration and are self-limited with return of normal health between episodes.
Even though the etiology and pathophysiology of CVS are not known, studies have suggested several potential brain-gut mechanisms.
Migraine, anxiety, endocrine factors, gastrointestinal motility disorders, autonomic dysfunction and genetic associationsMigraine, anxiety, endocrine factors, gastrointestinal motility disorders, autonomic dysfunction, allergy, and genetic associations…
A possible relationship between cyclic vomiting syndrome and mitochondrial dysfunction was suggested by the finding that in some families, CVS was maternally inherited. Mitochondrial DNA mutations and deletions have been reported in patients with CVS, and disease manifestations of mitochondrial dysfunction have been found in the maternal relatives of patients with CVS.
Subcategories of CVS have been identified, including CVS plus, catamenial CVS, and Sato’s variant of CVS.
The clinical course of CVS can be divided simply into the episode phase and the well phase, during which the person returns to his or her normal or baseline state of health. The episode phase is further divided into the prodrome as the person becomes ill up to the point at which vomiting begins, the vomiting phase, and the recovery phase during which the vomiting ceases and the person returns to baseline health. Each phase has therapeutic implications.
Cyclic vomiting syndrome is characterized by severe discrete episodes of nausea, vomiting, and lethargy. Approximately 25% of cases have coexisting neuromuscular disease manifestations (cyclic vomiting syndrome plus).
It has long been thought that CVS was a condition of childhood and adolescence. Now we know that adults also suffer from CVS. There is CVS that begins in childhood and may extend into adulthood as well as adult onset CVS.
The labels “cyclic vomiting syndrome” and “abdominal migraine” have, on occasion, been used interchangeably, but there are significant differences between migraine-associated cyclic vomiting and non-migraine-associated cyclic vomiting that support their separation.