Etiology, prognosis, and management of secondary pituitary abscesses forming in underlying pituitary adenomas

Pituitary abscesses occurring in pre-existing pituitary pathology like Rathke's cleft cyst or adenomas (secondary pituitary abscesses) are rare and of unclear etiology. While surgery and antibiotics have been effective in some cases reported to date, leading to the suggestion that secondary pituitary abscesses are mostly indolent, we investigated the hypothesis that infected adenomas, given their propensity to invade the paranasal sinuses and subarachnoid space, could carry a worse prognosis than uninfected adenomas or secondary abscesses forming in other pituitary pathologies. We identified infected adenomas from our center through retrospective review. Given the rarity of this diagnosis at any single center, we also reviewed published cases of secondary pituitary abscesses occurring in pituitary adenomas to look for common features. Twenty-three cases (19 from the literature and four from our center) of infected adenomas were identified. The mean age at presentation was 46 years, with 65 % male. The most common presenting symptoms were visual disturbances (83 %) and headache (65 %), followed by infectious signs like fever (39 %) and meningitis (26 %). The sphenoidal sinus was the most common site of extrasellar invasion. While good outcome occurred in 74 % of patients, and most achieved vision improvement, the mortality was 26 %. Patients with infected pituitary adenomas commonly present with visual disturbances and headache, with symptoms of infection also occurring. Surgery and antibiotics are indicated for these lesions. While the infection is more indolent than other intracranial abscesses, it is associated with high mortality even after prompt operation and antibiotic treatment.