Endocrine Abstracts

Background: In a vast majority of cases, hypopituitarism is caused by a tumour or a vascular event of the pituitary gland. We present a case of hypopituitarism caused by an uncommon cause identified on imaging studies.

Case: A 58-year-old Caucasian woman presented with a 2-day history of diplopia, headache and vomiting with a background history of tiredness and lethargy over the past 4–6 months. Past medical history included type-II diabetes, hypertension and obesity. She had smooth, pale, hairless skin and she was found to have left sided 3rd and 6th nerve palsy. Laboratory tests confirmed pan-anterior hypopituitarism. CT scan of head showed a non-enhancing, homogeneous mass of soft tissue density occupying the entire sphenoid sinus with destruction of the clivus and petrous apices. MRI scan showed the lesion to be isointense on T1-weighted and hyperintense on T2-weighted sequences with encroachment of optic chiasm and displacement of pituitary gland and cavernous sinus to the periphery. These appearances were consistent with those of a large sphenoid sinus mucocoele. Visual fields were normal on Goldman’s perimetery. She was commenced on 20 mg Hydrocortisone and 50 μg Thyroxine daily and underwent an emergency endoscopic left sphenoethmoidectomy with sphenoid mucocoele drainage. Histology showed changes of chronic inflammation and post-operative MRI confirmed successful drainage of the mucocoele. Her symptoms were relieved over the next few days and with a near-total recovery of ophthalmoplegia over the following 3 months. Pituitary function tests showed recovery of HPA axis and hydrocortisone therapy was withdrawn but she continued to require thyroxine.

Conclusions: Sphenoid sinus mucocoele is a rare cause of hypopituitarism. Endoscopic sphenoidotomy and drainage can lead to a cure of the condition and to a variable degree of recovery from hypopituitarism as was seen in our case.