A clinical case of identical twins with hypogonadotropic hypogonadism, primary empty sella syndrome and identified rare gene variant.

Key Clinical Message: Empty sella syndrome is a complex syndrome with a diverse clinical presentation. The combination with functional hypogonadotropic hypogonadism is a real challenge for the clinician. Mutations in the CHD7 gene could be a possible, yet unproven, cause of "empty sella" syndrome.