261. A Retrospective Evaluation of Coccidioidomycosis Skin Testing in Patients with Pulmonary Coccidioidomycosis in an Endemic Region

Abstract Background Making the decision to stop antifungal therapy in patients with coccidioidomycosis can be challenging in patients with risk factors for relapsed infection. Spherulin-based coccidioidal skin testing was re-introduced to the market in 2014 and approved for the detection of delayed-type hypersensitivity in patients with a history of pulmonary coccidioidomycosis Methods We searched electronically for patients who had a spherulin skin test placed in our institution from January 1, 2015 through March 1, 2017, and then included patients age 18 years and older who met the definition for confirmed or probable pulmonary coccidioidomycosis. A retrospective chart review was conducted, and included details of clinical illness, antifungal treatment, serology, and chest imaging Results From January 1, 2015 to August 31, 2017, 172 patients with coccidioidomycosis had a spherulin skin test placed. We included for further study the 129 patients who had primary pulmonary coccidioidomycosis, followed for a median of 18 months (range 0–50 months); 56 (43.4/%) were male, 108 (85.7/%) Caucasian, median age was 55 years (range18–89).19/12914.7%)) were smokers, 14/129 (10.9%) were diabetic, 2 patients had HIV (1.6%) and 15/129 (11.6) we immunocompromised without HIV. 116/129(89.9%) % received antifungal treatment. Median time from illness to skin test was 13.5 months (range 0–78). Eighty-nine of 129 patients (69%) had a positive skin test, 40 (31%) had a negative test. Antifungal treatment was subsequently discontinued in 75/89 (84%), and one patient (1.2%) with a positive test, experienced relapsed infection. Among 30/40 with negative CST, antifungals were discontinued and none relapsed. Conclusion The presence of delayed-type hypersensitivity to coccidioidomycosis, manifested by a positive spherulin skin test, was associated with discontinuation of antifungal therapy, and a low percentage of relapsed infection. Disclosures All authors: No reported disclosures.