Congenital Pituitary Stalk Interruption Syndrome in Children and Adolescents: MRI-Defined Anatomy, Evolving Hypopituitarism, and Growth Outcomes

Background: Congenital pituitary stalk interruption syndrome (PSIS) is a developmental disorder of the hypothalamo–pituitary axis defined radiologically by an absent or markedly thinned pituitary stalk, ectopic or absent posterior pituitary bright spot, and a hypoplastic anterior pituitary. In pediatrics, PSIS is a leading “organic” substrate for severe growth hormone deficiency (GHD) and a frequent cause of evolving multiple pituitary hormone deficiencies (MPHD/CPHD), yet clinical recognition is often delayed because initial manifestations vary by age and sex.

Objectives: (1) To summarize the anatomical hallmarks and radiological associations of PSIS in children/adolescents and their relationship to endocrine severity. (2) To synthesize the impact of PSIS on linear growth and the GH–IGF-1 axis, including response patterns to recombinant human GH (rhGH). (3) To outline a pragmatic, anatomy-informed management and surveillance approach for pediatric PSIS.

Methods: A narrative structured review of PubMed/Scopus-indexed pediatric literature (January 2001–December 2025) was performed using terms related to “pituitary stalk interruption,” “ectopic posterior pituitary,” “hypopituitarism,” “child*,” and “adolescent*.” We prioritized cohort studies with MRI-phenotype correlation and GH outcomes, and contemporary expert reviews/guidelines for replacement therapy. Extracted data included presentation triggers, frequency of pituitary deficits, auxology/IGF-1 characteristics, MRI patterns (complete vs partial PSIS), extra-pituitary malformations, and management implications.

Results: Across major pediatric cohorts, GHD is highly prevalent and commonly severe; central hypothyroidism, ACTH deficiency, and hypogonadotropic hypogonadism occur with variable frequencies, and deficiencies may progress over time (2–5). MRI severity—particularly non-visualization of the stalk and a smaller anterior pituitary—correlates with greater endocrine burden and earlier presentation (4,5). Manifestations range from early infancy signs (hypoglycemia, micropenis/cryptorchidism) to later childhood short stature. IGF-1 is frequently low at diagnosis, and rhGH typically induces robust first-year catch-up growth, with response modulated by age at start and baseline severity (2,7,8). PSIS frequently coexists with midline/extra-pituitary anomalies in subsets, reinforcing a developmental field defect model (2,6).

Conclusions: Pediatric PSIS is an MRI-defined congenital disorder with wide clinical expression but predictable anatomy–endocrine correlations. Early MRI recognition, complete baseline pituitary profiling, and longitudinal re-screening for evolving deficiencies are central to preventing morbidity. Growth outcomes are generally favorable when rhGH is initiated early and combined with timely replacement of other deficient axes.