(12.04) Panhypopituitarism Secondary To Pituitary Abscess

Pituitary abscess is a rare clinical entity, representing less than 1% of pituitary lesions, and is defined by the presence of an infected purulent collection within the sella turcica, which  can be a can be primary for an otherwise healthy patient or secondary, arising from an existing pituitary lesion such as an adenoma or a cyst), with or without a recent history of surgery.

Clinical presentation can be nonspecific with a lack of signs of systemic infection, making the diagnosis a challenge. The most common signs and symptoms include headache, diabetes insipidus, and hypopituitarism.

 We describe a case of a 59-year-old female patient with a secondary pituitary abscess, which was treated with surgical intervention and IV antibiotics.

Case(s) Description :

59 years old lady who was seen initially in September 2021 with a 2-month history of headaches, night sweats, and trouble sleeping. Her laboratory evaluation at that time showed an elevated prolactin of 96 with no other pituitary hormone abnormalities. She had a brain MRI that showed a 10 mm cystic mass located within the sella turcica without suprasellar extension or optic chiasm compression. She was seen by neurosurgery, and surgery was felt not indicated. She presented in March 2023 with 3-week history of worsening daily headaches, loss of peripheral vision and double vision, fatigability, and increased thirst with frequent urination. Labs showed a prolactin of 85, TSH of 1.4, FSH of 2.5, LH of less than 0.3 and a sodium of 145.  Her repeat MRI showed cystic degeneration of the pituitary lesion with extension to the optic chiasm. Given her symptoms and MRI findings, she underwent transsphenoidal surgery in April and was found to have a pituitary abscess which was drained surgically. Bacterial cultures grew Enterococcus faecalis and Staphylococcus epidermidis. 

 Her evaluation by endocrinology showed evidence of pan hypopituitarism with central hypothyroidism with a free T4 of 0.6 ng/dl, adrenal insufficiency with cosyntropin test showing maximum cortisol of 15 mcg/dl and diabetes insipidus for which he was started on hydrocortisone, levothyroxine and DDAVP.

 She completed a total of 8 weeks of IV ceftriaxone and vancomycin plus oral metronidazole with no recurrence of the pituitary abscess. 

Discussion :

Pituitary abscess is rare and the clinical diagnosis can be difficult to distinguish from other pituitary lesions with subacute manifestations similar to other pituitary masses with headaches, visual field defects and hormonal disturbances, with secondary adrenal insufficiency and diabetes insipidus being the most common hormonal deficiencies found.

Pituitary abscess should be considered in the differential diagnosis of all pituitary masses in patients with diabetes insipidus. For the correct preoperative diagnosis of this condition, the physician must have a high index of suspicion.

It is vital to continue monitoring patients with pituitary abscess for hormonal deficiencies even after the infection is cured because some may require indefinite treatment.