title: Paediatric cyclical Cushing's disease due to corticotroph cell hyperplasia.
abstract: BACKGROUND
  Cushing's disease is very rare in the paediatric population. Although uncommon, corticotroph hyperplasia causing Cushing's syndrome has been described in the adult population, but appears to be extremely rare in children. Likewise, cyclical cortisol hypersecretion, while accounting for 15 % of adult cases of Cushing's disease, has only rarely been described in the paediatric population. Here, we describe a very rare case of a 13-year old boy with cyclical cortisol hypersecretion secondary to corticotroph cell hyperplasia.
  
  
  METHODS
  The case is that of a 13-year old boy, presenting with a long history of symptoms and signs suggestive of hypercortisolism, who was found to have cyclical ACTH-dependent hypercortisolism following dynamic pituitary testing and serial late-night salivary cortisol measurements. The patient underwent endoscopic transsphenoidal resection of the pituitary. Early surgical remission was confirmed by undetectable post-operative morning plasma cortisol levels. Histology and immunocytochemistry of the resected pituitary tissue showed extensive corticotroph cell hyperplasia.
  
  
  CONCLUSIONS
  This report describes a rare case of cyclical Cushing's disease secondary to corticotroph hyperplasia in a paediatric patient. This highlights the challenging and varied nature of Cushing's disease and its diagnosis, and the need to keep a differential diagnosis in mind during the diagnostic process.
authors.affiliation: Department of Endocrinology and Neurosurgery, Beaumont Hospital, Beaumont Road, Dublin 9, Ireland. enoctor@yahoo.com.
authors.forename: E
authors.initials: E
authors.lastname: Noctor
authors.affiliation: Department of Endocrinology and Neurosurgery, Beaumont Hospital, Beaumont Road, Dublin 9, Ireland. saketgupta@beaumont.ie.
authors.forename: S
authors.initials: S
authors.lastname: Gupta
authors.affiliation: Department of Endocrinology and Neurosurgery, Beaumont Hospital, Beaumont Road, Dublin 9, Ireland. tara.brown@blackrock-clinic.com.
authors.forename: T
authors.initials: T
authors.lastname: Brown
authors.affiliation: Department of Neuropathology, Beaumont Hospital, Dublin, Ireland. michaelfarrell@beaumont.ie.
authors.forename: M
authors.initials: M
authors.lastname: Farrell
authors.affiliation: Department of Neurosurgery, Beaumont Hospital, Dublin, Ireland. mohsenjavadpour@beaumont.ie.
authors.forename: M
authors.initials: M
authors.lastname: Javadpour
authors.affiliation: Department of Paediatric Endocrinology, Our Lady's Hospital for Sick Children, Dublin, Ireland. colm.costigan@olchc.ie.
authors.forename: C
authors.initials: C
authors.lastname: Costigan
authors.affiliation: Department of Endocrinology and Neurosurgery, Beaumont Hospital, Beaumont Road, Dublin 9, Ireland. amaragha@beaumont.ie.
authors.forename: A
authors.initials: A
authors.lastname: Agha
mesh_terms: D000293:Adolescent; D052680:Corticotrophs / Q000473:pathology*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D006965:Hyperplasia / Q000175:diagnosis; D008297:Male; D010507:Periodicity; D047748:Pituitary ACTH Hypersecretion / Q000175:diagnosis*; D010900:Pituitary Diseases / Q000175:diagnosis*; D012463:Saliva / Q000737:chemistry
chemical_list: D006854:Hydrocortisone