What is pituitary stalk interruption syndrome?
Pituitary stalk interruption syndrome (PSIS) is characterized by the association of an absent or thin pituitary stalk, an absent or hypoplastic anterior pituitary lobe, and/or an ectopic posterior pituitary lobe. PSIS is a frequent cause of congenital hypopituitarism (50% of cases). Patients with PSIS are usually diagnosed with hypoglycemia during the neonatal period and growth hormone (GH) deficiency during childhood. Much less commonly, it is detected in adulthood as a sequela of traumatic brain/sheering injury. PSIS is either isolated (non-syndromic) or associated with extrapituitary malformations (syndromic), such as midline defects (i.e., craniofacial abnormalities) or optic nerve hypoplasia.