[Noonan's syndrome associated with cerebral hemorrhage. Report of a case].

The prevalence of Noonan syndrome has been estimated at between 1 out of 1000 and 1 out of 2500 live births; it is often confused with Turner syndrome because the two conditions display a common phenotype. Even if Noonan syndrome is typically associated with congenital heart diseases, prognosis is generally good. We describe the case of a female patient, deaf from infancy, in whom the presence of obstructive cardiomyopathy had been previously demonstrated angiographically at 29 years of age. A diagnosis of Turner syndrome had been made on the basis of her physical features. One year later she began to complain of accessional headache with nausea; seizures occurred at 48 years of age. The patient suddenly died during a hospital stay for investigation of these symptoms. Autopsy evidenced multiple cerebral hemorrhages due to vascular anomalies. She had normal female genitalia. This case demonstrates that Noonan syndrome is still misdiagnosed, and that it may have various clinical symptoms. In particular, it underscores the opportunity of carrying out systematic research on cerebrovascular abnormalities in these patients because they are potentially fatal.