title: Pituitary stalk interruption syndrome: a rare and severe cause of pituitary deficiency Laboratory diagnosis of a newborn case.
abstract: We report the case of a newborn with neonatal hypotonia associated to a micropenis and a bilateral cryptorchidia. The discovery of severe hypoglycemia at 0.22 mmol/L led to further biological investigations that revealed sharply decreased levels of several hypophyseal hormones. Altered corticotropic, somatotropic, thyreotropic, and gonadotropic axes finally suggested congenital hypophyseal insufficiency. This diagnostic was confirmed by a brain MRI (magnectic resonance imaging), which revealed a total interruption of the pituitary stalk. Immediate substitutive hormonal treatment allowed a clinical improvement of the condition and limited the risk of further episodes of hypoglycemia. The pituitary stalk interruption syndrome (PSIS), a very rare congenital disorder, has an estimated incidence of about 1:200.000. This developmental anomaly of the hypophysis calls for urgent diagnosis since prognosis depends on the rapid implementation of substitutive hormonal therapy. The hormonal deficit in the newborn affected by PSIS is often of a multiple nature with a constant somatotropic deficit, thus requiring the exploration of the different antehypophyseal axes. Despite the fact that PSIS is a rare disorder, it should always be kept in the differential diagnosis of newborn presenting with hypoglycemia. Since the interpretation of hormonal assays is particularly delicate at birth, close clinico-biological cooperation is essential for rapid diagnosis of PSIS and appropriate adaptation of the short- and long-term therapeutic management of the newborn.
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Boueilh
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Corentin
authors.initials: C
authors.lastname: Bassi
authors.affiliation: Département de pédiatrie, Centre hospitalier universitaire, Angers, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Rouleau
authors.affiliation: Service de laboratoire, Centre hospitalier, Cholet, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Le Crugel
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Moal
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Boux de Casson
authors.affiliation: Département de pédiatrie, Centre hospitalier universitaire, Angers, France.
authors.forename: Régis
authors.initials: R
authors.lastname: Coutant
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Mirebeau-Prunier
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Reynier
authors.affiliation: Département de biochimie et génétique, Centre hospitalier universitaire, Angers, France.
authors.forename: Chadi
authors.initials: C
authors.lastname: Homedan
mesh_terms: D019411:Clinical Laboratory Techniques; D006801:Humans; D007018:Hypopituitarism / Q000151:congenital / Q000175:diagnosis*; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D010902:Pituitary Gland / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012720:Severity of Illness Index; D013577:Syndrome
keywords: MRI; case report; pituitary stalk interruption syndrome