Endocrine Abstracts

Hypophysitis is an inflammatory disorder of the pituitary gland and among them, IgG-4 hypophysitis is rare and presents in less than 5 % of cases.

Case: 59 years old lady with a past medical history of asthma presented Rheumatology with? giant cell arthritis due to constant frontal headache, pain behind her eyes, and raised inflammatory markers (ESR 15, CRP 17) three weeks after COVID infection. After review, rheumatology team concluded unlikely giant cell arthritis and she was then seen by medical team who arranged MRV to exclude the central venous thrombosis due to raised BMI of 35 and recent COVID. MRV exclude thrombosis however there was a bulky pituitary gland. Subsequent MRI pituitary showed a 12 mm pituitary macroadenoma extending superiorly out of sella and contact the optic chiasm without compression or deviation. The visual field was normal. Hydrocortisone 10 mg in the morning, 5 mg in the afternoon, and 5 mg in the evening were started followed by Levothyroxine 50 mg a few weeks later. When reviewing in 2 months’ time she complained of left-sided vision changes and repeated visual field showed left upper quadrantanopia. An urgent MRI showed a rapidly enlarging hemorrhagic pituitary macroadenoma with a 6 mm increase in size with increasing chiasmatic compression. Endoscopic endonasal resection of the pituitary gland was performed and she recovered well from the surgery. Histopathology of pituitary biopsy showed IgG-4 hypophysitis. Interestingly measured IgG-4 was normal – 0.57 g/l (Reference range 0.0 – 1.3). CT chest, Abdomen, and Pelvis were performed to look for systemic involvement of IgG-4 and she was referred to the rheumatology team. There were no systemic features suggestive of IgG-4 with a negative autoimmune screen and clear CT chest, abdomen, and pelvis apart from an incidental finding of an 11 cm right ovarian dermoid cyst causing hydronephrosis which has been referred to Gynaecology for further management.

Conclusion: Many cases of IgG4 hypophysitis present as a part of a multisystemic disease however it can be present as isolated primary hypophysitis. Although systemic involvement will be less common in the latter, close follow-up is required for early recognition and further management.