1691. Cryptococcus Species Other than C. neoformans and C. gattii: Are They Clinically Significant?

BACKGROUND: Cryptococcus sp. is a major cause of opportunistic infections in immunocompromised patients, with nearly all cases due to C. neoformans or C. gattii. There are occasional reports of other Cryptococcus species causing invasive human disease. However, their epidemiology and clinical significance are not fully defined. We sought to describe the patients with cultures positive for Cryptococcus species other than neoformans and gattii. METHODS: A retrospective descriptive review of patients with cultures growing Cryptococcus species other than neoformans and gattii from November 2011 to February 2019. Clinical and laboratory data were analyzed. RESULTS: Out of 177 cases with a culture positive for Cryptococcus sp., 54 patients (mean age, 53.3 years; 61% men) had a culture for Cryptococcus other than neoformans and gattii. The most common species were unspecified non-neoformans/gattii (10), magnus (9), laurentii (8), and ater (7). Three patients had active malignancies and 15 were on immunosuppressive drugs, 6 due to transplant. The most common sites or specimens were skin (16), respiratory (16), urine (7), joint (3), intravascular catheter (2), cerebrospinal fluid (2), oral (2), peritoneal fluid, donor liver transplant, bone marrow, sinus, nail, and cornea. Whereas 21 (38.9%) cultures were obtained due to local symptoms, there was only one case of invasive disease, affecting the peritoneum, while the majority was either unaddressed (25) or considered contaminants (17). Only 12 patients received antifungal treatment, where sources were skin (4), oral (2), peritoneum, donor liver, respiratory, vascular catheter, urine, and nail. Antifungal drugs were fluconazole, itraconazole, clotrimazole, caspofungin, and griseofulvin, for a mean duration of 37.6 days. Among patients who were not treated, four died within 6 months but mostly of unrelated causes (3) or not known (1). CONCLUSION: This large series of patients with Cryptococcus sp. other than neoformans and gattii suggests that these species rarely cause clinically significant infection in humans. Only one case of invasive disease was found. DISCLOSURES: All authors: No reported disclosures.