Approach to the diagnosis and treatment of cyclic vomiting syndrome: a large single-center experience with 106 patients.

BACKGROUND: Cyclic vomiting syndrome is characterized by repeated, stereotypical vomiting episodes. The diagnosis is made by exclusion of other organic diseases, which can lead to extensive testing. It has been suggested that these patients can have mitochondrial dysfunction. The aim of the study was to examine the evaluation of our cyclic vomiting patients and to determine whether they had associated, undiagnosed metabolic abnormalities.

METHODS: This retrospective study included 106 patients aged <21 years at diagnosis. Information regarding medical history, laboratory, and imaging studies were collected. Metabolic studies in plasma and urine were obtained when patients were well and when patients were in a vomiting cycle, including plasma amino acids, acylcarnitines, and urine organic acids.

RESULTS: The mean age at diagnosis was 8.9 ± 5.0 years. Neuroimaging revealed previously unknown intracranial abnormalities in <10% of patients, none of whom explained the vomiting signs. Abdominal ultrasounds revealed abnormalities in 15% of patients during an acute episode and 7% of patients when well. Sixty-one patients had an upper gastrointestinal series, all of which were normal. A total of 92% of patients had laboratory testing with 38% indicating abnormalities possibly suggesting mitochondrial dysfunction.

CONCLUSIONS: This large, single-center study further evaluated the need for more focused evaluation in patients with suspected cyclic vomiting syndrome. Thirty-eight percent of our patients had abnormalities in blood and/or urine suggesting mitochondrial dysfunction, which requires more detailed investigation in the future.