PMON97 Pituitary Abscess: Long-term follow up

INTRODUCTION: In spite of recent advances in radiological evaluation, preoperative diagnosis of pituitary abscess is often difficult and the diagnosis is established at the time of surgery. Most patients present with a chronic and indolent course with few infective manifestations, thus mimicking a pituitary tumor. Although there are several case reports in literature, long term follow-up of these patients have not been reported previously. We report long-term follow-up of two patients with pituitary abscess who underwent trans-sphenoidal surgery (TSS). CASE 1: A 45-year-old female was seen in endocrine clinic for follow-up of a pituitary abscess diagnosed 22 years earlier. At the age of 23, the patient had severe headaches and bitemporal visual field defects. Workup included a pituitary MRI which revealed a 2.3 cm mass with compression of the optic chiasma. She denied any fever or chills. Detailed pituitary function confirmed secondary hypogonadism and secondary adrenal insufficiency. Because of the visual defects she underwent TSS which revealed the diagnosis of pituitary abscess. Additionally, the pituitary abscess was confirmed by histological examination and cultures from the abscess grew coagulase negative staphylococcus. Anaerobic and fungal cultures were negative. The patient was successfully treated with vancomycin, ceftazidime and metronidazole. After the TSS, she required treatment for diabetes insipidus, central hypothyroidism, adrenal insufficiency and hypogonadism. For the last 22 years she has had no further major illnesses and continues to require treatment for diabetes insipidus and hypopituitarism. CASE 2: A 37-year-old female underwent evaluation for migraines 7 years ago. During workup, a pituitary MRI showed a 6×5 mm lesion suggestive of a partially cystic microadenoma. The patient had worsening of her headaches and a follow-up MRI 6 weeks later showed an enlarging heterogeneous pituitary macroadenoma now 1.9×2.1×1.5cm, with marked effect on the optic chiasm. The patient underwent TSS and intraoperatively a diagnosis of pituitary abscess was made. Although cultures were negative for any pathogens, the patient received empiric antibiotic treatment with cefotaxime and metronidazole for 4 weeks. After the TSS, she developed central diabetes insipidus and hypopituitarism. Since surgery she has had no significant illness and has been leading an active life for the last 7 years. CONCLUSION: Both of these patients underwent treatment with TSS with an intraoperative diagnosis of pituitary abscess and were able to recover with no long-term sequelae or evidence of recurrent abscesses. They did however develop the common side effects of TSS surgery including diabetes insipidus and hypopituitarism, but are able to live a normal life on medical therapy. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.