Clonality of Fluconazole-Nonsusceptible Candida tropicalis in Bloodstream Infections, Taiwan, 2011-2017.

Candida tropicalis is the leading cause of non-C. albicans candidemia in tropical Asia and Latin America. We evaluated isolates from 344 patients with an initial episode of C. tropicalis candidemia. We found that 58 (16.9%) patients were infected by fluconazole-nonsusceptible (FNS) C. tropicalis with cross resistance to itraconazole, voriconazole, and posaconazole; 55.2% (32/58) of patients were azole-naive. Multilocus sequence typing analysis revealed FNS isolates were genetically closely related, but we did not see time- or place-clustering. Among the diploid sequence types (DSTs), we noted DST225, which has been reported from fruit in Taiwan and hospitals in Beijing, China, as well as DST376 and DST505-7, which also were reported from hospitals in Shanghai, China. Our findings suggest cross-boundary expansion of FNS C. tropicalis and highlight the importance of active surveillance of clinical isolates to detect dissemination of this pathogen and explore potential sources in the community.

In Vitro Evaluation of Povidone-Iodine and Chlorhexidine against Outbreak and Nonoutbreak Strains of Mycobacterium abscessus Using Standard Quantitative Suspension and Carrier Testing.

Povidone-iodine (PI) and chlorhexidine (CHX) are widely used antiseptics active against conventional Staphylococcus aureus, Enterobacteriaceae, Candida species, and viruses, but their efficacy against Mycobacterium abscessus remains unproven. We determined the in vitro potency of alcoholic PI and CHX against M. abscessus subsp. abscessus (ATCC 19977), M. abscessus subsp. bolletii (BCRC 16915), and our outbreak strain of M. abscessus subsp. massiliense (TPE 101) in reference to Staphylococcus aureus (ATCC 29213) by standard quantitative suspension and carrier methods (EN 14563). By suspension, all mycobacterial strains compared to S. aureus were significantly more resistant to CHX, but not PI. By carrier, the mean logarithmic reductions (LR) achieved by PI under clean (dirty) conditions were 6.575 (2.482), 5.540 (2.298), 4.595 (1.967), and 1.173 (0.889), while those achieved by CHX under clean (dirty) conditions were 3.164 (5.445), 5.307 (2.564), 3.844 (2.232), and 0.863 (0.389) for S. aureus, M. abscessus subsp. bolletii, M. abscessus subsp. abscessus, and M. abscessus subsp. massiliense, respectively. M. abscessus subsp. massiliense (outbreak strain) was significantly more resistant than the other tested strains to PI and CHX. By both methods, the mean LR achieved by PI was higher than for CHX for all mycobacterial strains, but under dirty conditions, neither antiseptic was effectively mycobactericidal (LR < 5). These preliminary findings caution against the universal replacement of PI with CHX as the first-line skin antiseptic, since all M. abscessus isolates were resistant to CHX. More studies are needed to establish the best practice for skin antisepsis if mycobacterial infections are also to be prevented.