TY - JOUR
T1 - Establishment of epidemiological cutoff values for clinically relevant Sporothrix species using CLSI-broth microdilution
AU - Dos Santos, Amanda R
AU - Bonifaz, Alexandro
AU - Bombassaro, Amanda
AU - Machado, Ana Caroline de Sá
AU - Rodrigues, Anderson M
AU - Borman, Andrew M
AU - Chakrabarti, Arunaloke
AU - Chowdary, Anuradha
AU - Rediguieri, Bruno
AU - Johnson, Elizabeth M
AU - Hagen, Ferry
AU - Queiroz-Telles, Flavio
AU - Gonzalez, Gloria M
AU - Garcia-Effron, Guillermo
AU - Dib Ferreira Gremião, Isabella
AU - Meis, Jacques F
AU - Takahashi, Juliana Possato Fernandes
AU - Borba Dos Santos, Luana Pereira
AU - Melhem, Marcia S C
AU - Cappellano, Paola
AU - Sâmia Nogueira Brilhante, Raimunda
AU - Pereira, Sandro Antonio
AU - Gonçalvez, Sarah Santos
AU - Kidd, Sarah
AU - Zhang, Sean X
AU - Rudramurthy, Shivaprakash
AU - Rozental, Sonia
AU - Cordoba, Susana
AU - De Groot, Theun
AU - Liu, Wei
AU - Wiederhold, Nathan P
AU - Meijer, Eelco F J
AU - Lockhart, Shawn R
AU - Dufresne, Philippe J
N1 - Publisher Copyright:
Copyright © 2026 dos Santos et al.
PY - 2026/5
Y1 - 2026/5
N2 - Sporotrichosis is a globally distributed subcutaneous mycosis caused mainly by Sporothrix brasiliensis, S. schenckii, and S. globosa. Cat-transmitted sporotrichosis, primarily caused by S. brasiliensis in South America and to a lesser extent by S. schenckii in Southeast Asia, is emerging as a substantial public health concern due to its outbreak potential. Itraconazole is the first-line drug for the treatment of humans and cats, but reduced susceptibility has been reported based on previously proposed epidemiological cut-off values (ECVs). To support resistance surveillance, we aimed to establish the Clinical and Laboratory Standards Institute (CLSI)-endorsed ECVs for these clinically relevant Sporothrix species. A total of 3,504 minimum inhibitory concentration (MIC) values for six antifungal agents (amphotericin B, itraconazole, posaconazole, voriconazole, isavuconazole, and terbinafine) were obtained from 19 international laboratories. Four of seven antifungals met the CLSI M57 guidelines criteria to determine the ECV. Established ECVs for amphotericin B were found to be high, with 8 µg/mL for S. brasiliensis and S. globosa, and 4 µg/mL for S. schenckii. Itraconazole ECVs were 4 µg/mL for S. brasiliensis and S. schenckii. Posaconazole ECVs were 4 µg/mL for all three species (tentative for S. globosa), while the terbinafine ECV for S. brasiliensis was 0.12 µg/mL. Overall, this study establishes validated ECVs for key antifungals against Sporothrix species and identifies a low prevalence of non-wild-type (NWT) isolates (<10% except for S. schenckii and posaconazole), supporting ongoing antifungal resistance monitoring.
AB - Sporotrichosis is a globally distributed subcutaneous mycosis caused mainly by Sporothrix brasiliensis, S. schenckii, and S. globosa. Cat-transmitted sporotrichosis, primarily caused by S. brasiliensis in South America and to a lesser extent by S. schenckii in Southeast Asia, is emerging as a substantial public health concern due to its outbreak potential. Itraconazole is the first-line drug for the treatment of humans and cats, but reduced susceptibility has been reported based on previously proposed epidemiological cut-off values (ECVs). To support resistance surveillance, we aimed to establish the Clinical and Laboratory Standards Institute (CLSI)-endorsed ECVs for these clinically relevant Sporothrix species. A total of 3,504 minimum inhibitory concentration (MIC) values for six antifungal agents (amphotericin B, itraconazole, posaconazole, voriconazole, isavuconazole, and terbinafine) were obtained from 19 international laboratories. Four of seven antifungals met the CLSI M57 guidelines criteria to determine the ECV. Established ECVs for amphotericin B were found to be high, with 8 µg/mL for S. brasiliensis and S. globosa, and 4 µg/mL for S. schenckii. Itraconazole ECVs were 4 µg/mL for S. brasiliensis and S. schenckii. Posaconazole ECVs were 4 µg/mL for all three species (tentative for S. globosa), while the terbinafine ECV for S. brasiliensis was 0.12 µg/mL. Overall, this study establishes validated ECVs for key antifungals against Sporothrix species and identifies a low prevalence of non-wild-type (NWT) isolates (<10% except for S. schenckii and posaconazole), supporting ongoing antifungal resistance monitoring.
KW - Sporothrix spp
KW - antifungal susceptibility testing
KW - zoonotic
KW - epidemiological cutoff values (ECV)
KW - sporotrichosis
UR - https://www.scopus.com/pages/publications/105038226273
U2 - 10.1128/aac.01907-25
DO - 10.1128/aac.01907-25
M3 - Article
C2 - 41940808
SN - 0066-4804
VL - 70
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
IS - 5
M1 - e0190725
ER -