title: Hypothalamic-Pituitary Autoimmunity and Traumatic Brain Injury.
abstract: BACKGROUND
  Traumatic brain injury (TBI) is a leading cause of secondary hypopituitarism in children and adults, and is responsible for impaired quality of life, disabilities and compromised development. Alterations of pituitary function can occur at any time after the traumatic event, presenting in various ways and evolving during time, so they require appropriate screening for early detection and treatment. Although the exact pathophysiology is unknown, several mechanisms have been hypothesized, including hypothalamic-pituitary autoimmunity (HP-A). The aim of this study was to systematically review literature on the association between HP-A and TBI-induced hypopituitarism. Major pitfalls related to the HP-A investigation were also discussed.
  
  
  METHODS
  The PubMed database was searched with a string developed for this purpose, without temporal or language limits, for original articles assessing the association of HP-A and TBI-induced hypopituitarism.
  
  
  RESULTS
  Three articles from the same group met the inclusion criteria. Anti-pituitary and anti-hypothalamic antibodies were detected using indirect immunofluorescence in a significant number of patients with acute and chronic TBI. Elevated antibody titer was associated with an increased risk of persistent hypopituitarism, especially somatotroph and gonadotroph deficiency, while no correlations were found with clinical parameters.
  
  
  CONCLUSIONS
  HPA seems to contribute to TBI-induced pituitary damage, although major methodological issues need to be overcome and larger studies are warranted to confirm these preliminary data.
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin, Corso Dogliotti 14, Turin 10126, Italy. federica.guaraldi@unito.it.
authors.forename: Federica
authors.initials: F
authors.lastname: Guaraldi
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin, Corso Dogliotti 14, Turin 10126, Italy. silvia.grottoli@unito.it.
authors.forename: Silvia
authors.initials: S
authors.lastname: Grottoli
authors.affiliation: Division of Oncological Endocrinology, Department of Medical Sciences, University of Turin, Corso Bramante 88, Turin 10126, Italy. emanuela.arvat@unito.it.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Arvat
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin, Corso Dogliotti 14, Turin 10126, Italy. ezio.ghigo@unito.it.
authors.forename: Ezio
authors.initials: E
authors.lastname: Ghigo
keywords: antihypothalamic antibodies; antipituitary antibodies; brain trauma injury; hypothalamic-pituitary autoimmunity