ABSTRACT
Cyclic vomiting syndrome (CVS) is a functional disorder characterized by stereotypical episodes of intense vomiting separated by weeks to months. Although it can occur at any age, the most common age at presentation is 3-7 years. There is no gender predominance. The precise pathophysiology of CVS is not known but a strong association with migraine headaches, in the patient as well as the mother indicates that it may represent a mitochondriopathy. Studies have also suggested the role of an underlying autonomic neuropathy involving the sympathetic nervous system in its pathogenesis. CVS has known triggers in many individuals and avoiding these triggers can help prevent the onset of the episodes. It typically presents in four phases: a prodrome, vomiting phase, recovery phase and an asymptomatic phase until the next episode. Complications such as dehydration and hematemesis from Mallory Wise tear of the esophageal mucosa may occur in more severe cases. Blood and urine tests and abdominal imaging may be indicated depending upon the severity of symptoms. Brain magnetic resonance imaging and upper gastrointestinal endoscopy may also be indicated in certain circumstances. Management of an episode after it has started ('abortive treatment') includes keeping the patient in a dark and quiet room, intravenous hydration, ondansetron, sumatriptan, clonidine, and benzodiazepines. Prophylactic treatment includes cyproheptadine, propranolol and amitriptyline. No mortality has been reported as a direct result of CVS and many children outgrow it over time. A subset may develop other functional disorders like irritable bowel syndrome and migraine headaches.
ABSTRACT
OBJECTIVE: To report the autosomal dominant inheritance of the Jervell and Lange-Nielsen syndrome in a highly inbred family, the initiation of Torsades de Pointes, and the natural history of the syndrome based on a 16-year follow-up of the kindred. METHOD: A family tree was constructed that included 66 blood relatives from three successive generations. Electrocardiograms were obtained from 59 living members including the proband, four members from a nuclear family, and 54 from the extended family. Evoked response audiometry was recorded for the proband and the nuclear family. All 59 family members were followed up regularly for 16 years. RESULTS: A total of 24 living members were affected--QTc: 480-680 ms. The proband had long QTc, bilateral high-tone sensorineural deafness, recurrent syncope, and Torsades de Pointes. The asymptomatic father had long QTc and unilateral high-tone sensorineural deafness that involved specifically the left ear. One asymptomatic sibling of the proband had long QTc and normal hearing. The mother and another sibling were asymptomatic; QTc and hearing were normal in both. A total of 21 affected members from the extended family had only long QTc, and all were asymptomatic. There were three congenitally deaf first cousins who had recurrent syncope and adrenergic-triggered sudden death. In all, seven of 10 parents had consanguineous marriage to a first cousin. Each affected offspring had at least one affected parent. The severely symptomatic proband who received only ß-blocker therapy and the 23 affected members without antiadrenergic therapy, all remained asymptomatic throughout the 16-year follow-up period. CONCLUSION: Jervell and Lange-Nielsen syndrome was inherited as autosomal dominant in this kindred. The majority of the affected members had a mild phenotype. The severity of auditory and cardiac phenotypes corresponded.
