Endocrine Abstracts

Introduction: Pituitary adenomas are benign tumours of the pituitary gland with an estimated prevalence rate of approximately 17%. Around 1 in 600 people have macroadenoma (>1cm) that can present with variety of visual problems classically as bitemporal hemianopia due to compression of the optic chiasm.

Case presentation: 50-year-old male was admitted with 3months history of worsening headache and 4months of visual disturbances. Initially he was seen in an eye clinic and diagnosed with cataract however, on the day of his cataract operation was told he does not have cataract and was sent for further investigations. In the past 4weeks his headaches had escalated to 10/10 pain severity scale that was not relieved by analgesia and his vision was getting worse. He reports of change in shoe size and his ring no longer fitting. He complained of increased frequency of urination, snoring at night-time and intermittent sweating. On examination he was found to have bitemporal hemianopia more severe on the right inferior quadrants, reduced nasal field on the right eye but rest of the cranial nerves were intact. His lower jaw was producing but no evidence of overbite or large hands. Nil significant past medical history.

Investigations: MRI pituitary showed large pituitary lesion measuring 4.8x1.7x2.9 cm extending into suprasellar cistern and compressing the optic chiasm and the hypothalamus and part of the floor of the third ventricle. The lesion is extending downward into the sphenoid sinus.

High prolactin 12788

Low cortisol level of 34

Low T4 (3.4) and T3 (2.8) (TSH normal)

Low FSH (0.9) and LH (<0.3)

Low testosterone(<0.1)

Low IGF-1 (60)

Management: Referred to the neuro-pituitary MDT. Commenced on cabergoline and prolactin decreased from 12788 to 2846 after one week Also started on hydrocortisone 10mg twice daily and levothyroxine 50micrograms daily. Endoscopic transsphenoidal surgery for pituitary lesion was carried out.

Discussion: Visual disturbances in particular bitemporal hemianopia is a common clinical presentation in pituitary macroadenomas however, in this case the patient initially presented at an Eye Clinic hospital and was diagnosed as cataract which is not common. Pituitary macroadenoma in particularly prolactinomas can be managed conservatively with dopamine agonist such as cabergoline however, in certain cases such as patients with resistant or intolerance to domine agonist, or worsening vison an endoscopic transsphenoidal surgery may be offered.

Conclusion: It is important to consider cranial or pituitary issues as differentials when seeing patients complaining with headache and visual changes.