Endocrine Abstracts

Introduction: Pituitary inflammation (Hypophysitis) is rare in paediatric population and usually results in pituitary enlargement and hypopituitarism. Hypophysitis can be either primary (most commonly lymphocytic, granulomatous or xanthomatous disease) or secondary (consequent to systemic diseases, immunotherapy or alternative sella-based pathologies). We describe the clinical presentation and management of apparent primary lymphocytic hypophysitis in an adolescent girl. Case report: A 16-year-old previously healthy girl presented with a 4 month history of headaches, vomiting and lethargy. Non-response to migraine treatment with beta blockers and sumatriptan culminated in MRI head, which identified a T2-hyperintense sellar/suprasellar lesion with a thick rim of enhancement and minimal sella expansion. Subsequent investigations showed hyperprolactinemia (1060mIU/l), TSH deficiency (fT4 7.4pmol/l, TSH 0.84mIU/l), and ACTH deficiency (30minute cortisol 287nmol/l on standard Synacthen test). Ophthalmological assessment showed normal visual acuity and fields. Treatment with hydrocortisone and levothyroxine was started. In view of proximity to the optic chiasm and uncertain diagnosis, our Pituitary Multidisciplinary Team agreed to proceed to trans-sphenoidal debulking and diagnostic biopsy. After opening the dura, yellowish necrotic pituitary tissue was observed and removed. Histologic examination showed non-neoplastic anterior pituitary tissue with prominent macrophagic and chronic lymphocytic inflammatory reaction. Although there were granulomata formation and cholesterol clefts suggesting inflammation secondary to ruptured Rathke’s cleft cyst, there were no epithelial cells to support that diagnosis. Histology did not favour IgG4-related hypophysitis. Headaches and lethargy completely resolved. Six weeks post-surgery, glucagon stimulation test was consistent with growth hormone (GH) deficiency and GH was started. At last review (3 months post-surgery), she was on multiple pituitary hormone replacements and was due post-operative surveillance MRI. Her menses had not yet restarted. Conclusion: Modern imaging techniques, histological classification and immune profiling have improved the accuracy of the diagnosis in patients with hypophysitis. Given the rarity of this condition in paediatric population, paediatric and young adult patients benefit from shared management with a multidisciplinary team involving adult Specialist colleagues. Careful follow-up is required to manage the endocrine deficiencies and seek to define a specific causal diagnosis if possible over time. A registry to understand the optimal management and outcomes of this rare condition is desirable.