2026 Poster Presentations
P193: RATES OF POSTOPERATIVE MENINGITIS WITH MINIMAL ANTISEPTIC PROTOCOL: A RETROSPECTIVE INSTITUTIONAL REVIEW
Hailey Mattheisen; Abdullah A Memon; Abigail Peterson; Sara Saleh, MD; Lauren North, MD; Stephanie Cheok, MD; Nathan Zwagerman, MD; Medical College of Wisconsin
Introduction: Meningitis is a rare, but serious complication following pituitary adenoma (PA) resection via an endoscopic endonasal approach (EEA). The risk is greater in the setting of a cerebrospinal fluid (CSF) leak. Reported rates of postoperative CSF leak range from 0.6-8.7%. To minimize this risk, some centers have published their antibiotic and antiseptic regimens highlighting significant practice variation. The utility of nasal antiseptic preparation and postoperative antibiotic use remains unclear. Herein we describe our minimal intraoperative and postoperative protocol and report our institutional rates of iatrogenic meningitis.
Methods: We retrospectively reviewed 171 patients with PAs who underwent EEA at our institution from January 2023- December 2024. Patient demographics, intraoperative and postoperative course, and infections were analyzed. For our antiseptic protocol, patients receive general anesthetic induction, line placement, and a single weight-based dose of prophylactic intravenous cefazolin. The face and nasal cavities are not prepared with antiseptic solution. Irrigation is normal saline, without impregnated antibiotics. Lumbar drains are not routinely placed, even with large CSF leaks. Prophylactic postoperative antibiotics are not used.
Results: Our cohort consisted of 99 females (57.9%) with an average age of 51 years (range 21-87 years) and 72 males (42.1%) with an average age of 59 years (range 34-81 years). PA subtypes included 74 non-functioning adenomas, 37 patients with Cushing’s disease, 21 with Acromegaly, 15 Silent ACTH, 14 prolactinomas, and 2 TSHomas (Table 1). Intraoperative CSF leaks were encountered in 42 patients (24.5%). Two patients (1.1%) developed postoperative meningitis confirmed with lumbar puncture. One case occurred in a patient with acromegaly who had an intraoperative CSF leak repaired with DuraMatrix and nasoseptal flap. 14 days postoperatively, the patient was readmitted after presenting with a fever and altered mental status. Lumbar puncture (LP) and blood culture grew E. coli, and the patient underwent placement of a lumbar drain and was started on vancomycin, cefepime, and flagyl.
The second patient had pituitary apoplexy with focal positivity for prolactin. There was no visualization of an intraoperative leak, but the patient was readmitted 5 days postoperatively with a fever, encephalopathy, and concerns for a CSF leak. LP and sinus cultures confirmed the presence of S.aureus and fusobacterium, and the patient was started on IV ceftriaxone, oral metronidazole, and oral valacyclovir for meningitis and co-infection of shingles. Further nasal endoscopy confirmed a CSF leak, and the patient underwent surgical repair 10 days after initial surgery.
Discussion: Literature remains sparse and there is significant heterogeneity in surgical preparation and antibiotic regimens in patients undergoing EEA. We describe our institution’s minimalist approach to peri-operative antiseptic and antibiotic regimens, based on current practice in standard sinus surgery. Our rates of meningitis are low at 1.1%, in line with reported frequency within our field. This is not to say that our method is superior but is a call to reevaluate current protocols and generate discussion on developing best practices.
Conclusion: Our findings demonstrate an acceptably low rate of post-operative meningitis following EEA for pituitary adenomas, even in the absence of antiseptic nasal preparation and postoperative antibiotics.
