MON-253 A Rare Case of Pituitary Aspergillosis Diagnosed by CSF PCR in an Immunocompetent Patient with Headaches and Photophobia

Background: Pituitary aspergillosis is a rare infection usually found in the immunocompromised population. It is oftentimes mistaken for a pituitary adenoma based on similar clinical presentation and characteristic findings on MRI. Most cases require removal of the pituitary mass in order to make a diagnosis. Here we present the case of an immunocompetent patient with headaches and photophobia diagnosed with pituitary aspergillosis by CSF PCR and treated medically with voriconazole. Clinical Case: A 40-year-old woman with a questionable history of Brucellosis presented with a 3 month history of headaches along with 2 days of nausea and vomiting. Vital signs were notable for intermittent hypotension but were otherwise within normal limits. Physical exam was notable for tenderness at the left temporal region, diaphoresis and photophobia. Patient was otherwise alert and oriented and had no visual field deficits or extraocular muscle dysfunction. Patient was found to have central adrenal insufficiency with undetectable AM cortisol (<0.5 mcg/dL, n 3.7-19.4 mcg/dL), inappropriately normal ACTH (7 pg/mL, n 6-58 pg/mL) and central hypothyroidism with low TSH (0.057 mcIU/mL, n 0.358-3.8 mcIU/mL) and low free T4 (0.48 ng/dL, n 0.76-1.46 ng/dL). Patient initially presented with hyponatremia (Na 119 mmol/L, n 137-145 mmol/L) likely secondary to central adrenal insufficiency and central hypothyroidism. Gadolinium-enhanced pituitary MRI showed a heterogeneous 1.8 cm pituitary mass with rim enhancement concerning for hypophysitis. Patient was started on stress-dose steroids with IV hydrocortisone 100 mg IV q8h, levothyroxine 50 mcg PO daily and empiric antibiotic therapy with ceftriaxone, doxycycline and rifampin due to suspicion for neurobrucellosis. Lumbar puncture was obtained showing low glucose (39 mg/dL, n 40-70 mg/dL), normal protein (47 mg/dL, n 12-60 mg/dL) and an elevated white count (WBC 9/mcL, n 0-5/mcL) with lymphocyte predominance (97% lymphocytes, n 40-80%). Blood and CSF cultures showed no growth at 2 weeks. CSF was sent for multiplex PCR which came back positive for Aspergillus. Patient was discharged with voriconazole 300 mg PO BID for 1 year, levothyroxine 75 mcg PO daily and hydrocortisone 10 mg PO Qam and 5 mg PO Qpm. Three months later, repeat MRI showed resolution of the pituitary mass and patient felt well without headaches, nausea or vomiting. Conclusion: This case demonstrates an atypical example of pituitary aspergillosis diagnosed without pituitary mass biopsy and treated medically with voriconazole. It demonstrates the possible role of CSF PCR to diagnose the condition and guide antifungal treatment.