Cranial nerve manifestations in CHARGE syndrome.

Cranial nerve (CN) anomalies have been regarded as a major criterion for a clinical diagnosis of CHARGE syndrome for some time. However, there have been relatively few studies of the extent of this involvement. A detailed questionnaire (in French or English) was distributed to all physicians who participated in the 2001-2004 Canadian Paediatric Surveillance Program (CPSP), and who identified themselves as caring for an individual with CHARGE syndrome. Clinical data were collected from multiple sources for each individual, including evidence of CN dysfunction. Evidence for CN anomalies recorded by the clinical presentations and evidence from specialized testing, were: weak chewing and/or sucking (CN V), facial palsy (CN VII), sensorineural hearing loss (CN VIII), balance vestibular problems (CN VIII), and swallowing problems (CN IX/X). Data were analyzed as to the frequency of the CN anomalies and compared to the literature. At the time of this study, there were 99 individuals identified with CHARGE syndrome across Canada. The CHARGE syndrome diagnosis was confirmed by geneticists across the country. Gene testing was not available at the time of this study. Of these 92% exhibited symptoms of at least one CN anomaly, and 72% reported involvement of more than one. Isolated CN involvement was rare. Ascertainment was highest for CN IX/X, and lowest for VIII vestibular. The frequency of CN involvement was generally higher than that reported in the literature.