CASE: A 68-year-old female with a 4 year history of panhypopituitarism requiring thyroxine, cortisol and demospressin replacement secondary to a suspected Rathke’s cleft cyst(RCC), presented with worsening vision and headaches. MRI of the pituitary demonstrated enlargement of the known cystic pituitary lesion with compression of the optic chiasm. She underwent transphenoidal surgery (TSS) which revealed frank pus in the sella. Histopathology showed features of chronic inflammation and suppuration in keeping with an abscess. No organisms were seen on gram stain or .
Eight months after TSS she represented with headaches, visual disturbance and a left sixth nerve palsy. There were no symptoms of sepsis. MRI demonstrated recurrence of this cystic lesion.
Further TSS revealed pus in the lesion. Histopathology of the resected tissue showed a RCC with surrounding chronic inflammation demonstrated by an epithelial lining adjacent to inflammatory infiltrate, fibrous tissue and proteinaceous material. Gram stain and culture again did not identify any organism. Patient was treated with oral trimethoprim/sulfamethoxazole for a period of 4 weeks. Repeat imaging showed re-accumulation of cyst fluid. A trial of high dose glucocorticoid steroids could be considered to treat secondary hypophysitis.
Discussion: Pituitary abscess is a rare cause of a pituitary mass. Clinical features are variable and include headaches and pituitary hypofunction ( over 50% cases), visual disturbance (25 - 45% cases) and fever (33 – 44%).1, 2 MRI imaging may demonstrate a rim enhancing lesion in the pituitary.3 Cultures are often negative. Abscesses often occur secondary to an underlying pituitary lesion such as a RCC. Both abscesses and hypophysitis have been described to occur secondary to RCC and must be differentiated based on clinical, radiological, histological and microbiological findings. 4