Targeted whole-exome sequencing (WES) is a powerful diagnostic tool for a broad spectrum of heterogeneous neurological disorders. Here, we aim to examine the impact on diagnosis, treatment and cost with early use of targeted WES in early-onset epilepsy. WES was performed on 180 patients with early-onset epilepsy (≤5 years) of unknown cause. Patients were classified as Retrospective (epilepsy diagnosis >6 months) or Prospective (epilepsy diagnosis <6 months). WES was performed on an Ion Proton™ and variant reporting was restricted to the sequences of 620 known epilepsy genes. Diagnostic yield and time to diagnosis were calculated. An analysis of cost and impact on treatment was also performed. A molecular diagnoses (pathogenic/likely pathogenic variants) was achieved in 59/180 patients (33%). Clinical management changed following WES findings in 23 of 59 diagnosed patients (39%) or 13% of all patients. A possible diagnosis was identified in 21 additional patients (12%) for whom supporting evidence is pending. Time from epilepsy onset to a genetic diagnosis was faster when WES was performed early in the diagnostic process (mean: 145 days Prospective vs. 2,882 days Retrospective). Costs of prior negative tests averaged $8,344 per patient in the Retrospective group, suggesting savings of $5,110 per patient using WES. These results highlight the diagnostic yield, clinical utility and potential cost-effectiveness of using targeted WES early in the diagnostic workup of patients with unexplained early-onset epilepsy. The costs and clinical benefits are likely to continue to improve. Advances in precision medicine and further studies regarding impact on long-term clinical outcome will be important.

There are few published reports of adults with Williams syndrome (WS). We have evaluated ten adult WS patients. The patients in our study were very variable in clinical presentation, ranging from severely affected patients with complicated medical histories to mildly affected patients who are generally in good health. Cardiovascular anomalies and hypertension were frequent. Supravalvular aortic stenosis was seen in four patients, mitral valve prolapse in three, bicuspid aortic valve in one, valvular aortic stenosis in one, and pulmonary stenosis with right ventricular hypertrophy in one. Typical facial features included stellate irides, prominent cheeks, full lips, and micrognathia. Mental retardation was seen in all patients. Verbal skills were better developed than motor skills. All patients in our study lead active lives, and most are involved in sports. Some hold supervised jobs. Eight of our patients live with their parents and two in group homes. Independent living is restricted by their mental and adaptive limitations.

The findings of cranial synostosis, multiple symphalangism, and long-bone abnormalities in our case are typical of other reported cases of fluconazole embryopathy. Our patient showed no evidence of embryopathy due to efavirenz, and he did not have the features of Antley-Bixler or other craniosynostosis syndromes. We review the literature regarding the teratogenic effects of prenatal exposure to fluconazole and provide additional evidence that prenatal fluconazole exposure has a clearly identifiable phenotype.