Endocrine Abstracts

Background: Pituitary abscess is rare but a serious intrasellar infection. It should be considered in the differential diagnosis of the sellar masses due to its high morbidity and mortality rates. Despite recent advances in radiological investigations, it remains a challenge to make a definitive diagnosis preoperatively ^[1]. We present a case of pituitary abscess who presented with pan hypopituitarism and central diabetes insipidus.

Case presentation: A 34-year-old man with no significant past medical history was referred to the medical unit with a low serum cortisol (14 nmol/l). He had a 3 month history of fatigue, polyuria, polydipsia, cold intolerance and reduced libido, as well as a 1 week history of frontal headache worse with coughing and movement. No visual disturbances were present. Clinical examination and observations were normal. Routine blood tests revealed no electrolyte abnormalities with mild leucocytosis. Further investigations demonstrated pan hypopituitarism with secondary adrenal insufficiency, central hypothyroidism, and secondary hypogonadism. Central diabetes insipidus was suspected. Hydrocortisone, levothyroxine and testosterone were started initially, then desmopressin added due to ongoing polyuria, all with good symptomatic effect. MRI pituitary with contrast showed a 13x9mm lesion with peripheral enhancement and cystic-like component within the pituitary gland. Following referral to the pituitary MDT, he underwent endoscopic trans-sphenoidal pituitary surgery where pus was noted in the pituitary fossa. Drainage of the pituitary abscess was performed. Pus samples grew Staphylococcus aureus. He was treated with intravenous cefotaxime then switched to oral linezolid for a total of 4 weeks’ treatment. Post-operative MRI showed reduction in the cystic pituitary lesion. Patient remained on hormone replacement therapy.

Conclusion: To conclude we can say that, despite rarity of the condition and radiological uncertainty, the history of recent infection or surgery of nearby structures or immunosuppression makes it highly suspicious of pituitary abscess. Although these risk factors were not apparent in our case. Prompt surgical drainage of the abscess followed by prolonged antibiotic therapy and hormonal replacement remains the main stay of treatment ^[2].

References: 1. Dalan R, Leow MK. Pituitary abscess: our experience with a case and a review of the literature. Pituitary. 2008 Sep; 11(3):299-306. 2. Zhang X, Yu G, Du Z, Tran V, Zhu W, Hua W. Secondary pituitary abscess inside adenoma: A case report and review of literature. World Neurosurgery. 2020 May 1; 137:281-5.