Subcategories of CVS have been identified, including CVS plus, catamenial CVS, and Sato’s
variant of CVS.
CVS plus is defined by the presence of at least two or more neuromuscular disease manifestations, including cognitive disorders, skeletal myopathy, cranial nerve dysfunction, and seizure disorders. Children with CVS plus are more likely to present at an earlier age and have dysautonomia-related disorders such as migraine, chronic fatigue, and neurovascular dystrophy. Catamenial CVS coincides with a menstrual cycle, and the Sato’s variant of CVS was described in children who presented with emesis, hypertension, and depression. With attacks, they were found to have transient hyperglycemia and glycosuria; elevated plasma adrenocorticotropic hormone (ACTH), cortisol, and urinary 17-OHCS excretion; and low plasma osmolality with hyponatremia.
Cyclic vomiting syndrome subgroups include:
1. Those with migraine
2. Hypertension during episodes (Sato variant)
3. Catamenial CVS
4. Diabetes subgroup
5. Those with co-existing neuromuscular disorders (CVS plus)
6. Association with extreme anxiety
7. Morning nausea and/or vomiting only
8. Postinfectious subgroup.
It is not known if these different CVS subgroups exhibit different responses to the varied treatments used for the condition.