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.
Coccidioides (spherulin) skin testing in patients with pulmonary coccidioidomycosis in an endemic region†
Abstract Coccidioidomycosis is an endemic fungal infection of the desert southwestern United States. Intact cellular immunity is critical to the control of this infection. A recently released reformulated spherulin antigen (Spherusol; Nielsen BioSciences, Inc.) was approved to detect delayed-type hypersensitivity, which implies the presence of cellular immunity, to Coccidioides species. We aimed to summarize our experience with this test in patients with primary pulmonary coccidioidomycosis. We retrospectively reviewed clinical data for all patients with primary pulmonary coccidioidomycosis who had a Coccidioides (spherulin) skin test (CST) placed at our institution between January 1, 2015, and August 31, 2017. During the study period, 172 patients had a CST placed, and 122 met our inclusion criteria for proven or probable pulmonary coccidioidomycosis. Of these 122, 88 (72.1%) had a positive CST result and 34 (27.9%) had a negative result. In the positive CST group, 74 of the 79 treated patients (93.7%) had antifungal treatment stopped, 1 of whom (1.4%) had relapsed infection. In contrast, 27 of the 33 treated patients in the negative CST group (81.8%) had their antifungal treatment stopped, and none had a relapse. Seven patients overall (5.7%), all of whom had a positive CST, experienced mild local adverse reactions to the CST. Although previous controlled studies of CST showed sensitivity and specificity greater than 98%, our real-world experience with the CST showed lower rates of positivity. Negative CST results did not predict relapse with antifungal agent withdrawal.
Basidiobolomycosis: an unusual, mysterious, and emerging endemic fungal infection