{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Castro BE"],"funding":["NIAID NIH HHS"],"pagination":["2424-2431"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC7443737"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["75(9)"],"pubmed_abstract":["<h4>Background</h4>Vancomycin is a common first-line option for MRSA infections. The heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) phenotype is associated with therapeutic failure. However, hVISA isolates are usually reported as vancomycin susceptible by routine susceptibility testing procedures.<h4>Objectives</h4>To detect and characterize the hVISA phenotype in MRSA isolates causing infections in nine Latin American countries.<h4>Methods</h4>We evaluated a total of 1189 vancomycin-susceptible MRSA isolates recovered during 2006-08 and 2011-14. After an initial screening of hVISA using glycopeptide-supplemented agar strategies, the detection of hVISA was performed by Etest (GRD) and Macro-method (MET). Isolates deemed to be hVISA were subjected to population analysis profile/AUC (PAP/AUC) and WGS for further characterization. Finally, we interrogated alterations in predicted proteins associated with the development of the VISA phenotype in both hVISA and vancomycin-susceptible S. aureus (VSSA) genomes.<h4>Results</h4>A total of 39 MRSA isolates (3.3%) were classified as hVISA (1.4% and 5.6% in MRSA recovered from 2006-08 and 2011-14, respectively). Most of the hVISA strains (95%) belonged to clonal complex (CC) 5. Only 6/39 hVISA isolates were categorized as hVISA by PAP/AUC, with 6 other isolates close (0.87-0.89) to the cut-off (0.9). The majority of the 39 hVISA isolates exhibited the Leu-14→Ile (90%) and VraT Glu-156→Gly (90%) amino acid substitutions in WalK. Additionally, we identified 10 substitutions present only in hVISA isolates, involving WalK, VraS, RpoB and RpoC proteins.<h4>Conclusions</h4>The hVISA phenotype exhibits low frequency in Latin America. Amino acid substitutions in proteins involved in cell envelope homeostasis and RNA synthesis were commonly identified. Our results suggest that Etest-based methods are an important alternative for the detection of hVISA clinical isolates."],"journal":["The Journal of antimicrobial chemotherapy"],"pubmed_title":["Detection of heterogeneous vancomycin intermediate resistance in MRSA isolates from Latin America."],"pmcid":["PMC7443737"],"funding_grant_id":["R01 AI134637","R21 AI143229","K24 AI121296"],"pubmed_authors":["Rios R","Dinh A","Millan LV","Vargas ML","Forero E","Hernandez AK","Reyes J","Castro BE","Rincon S","Berrio M","Diaz L","Carvajal LP","Seas C","Cubides P","Munita JM","Arias CA"],"additional_accession":[]},"is_claimable":false,"name":"Detection of heterogeneous vancomycin intermediate resistance in MRSA isolates from Latin America.","description":"<h4>Background</h4>Vancomycin is a common first-line option for MRSA infections. The heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) phenotype is associated with therapeutic failure. However, hVISA isolates are usually reported as vancomycin susceptible by routine susceptibility testing procedures.<h4>Objectives</h4>To detect and characterize the hVISA phenotype in MRSA isolates causing infections in nine Latin American countries.<h4>Methods</h4>We evaluated a total of 1189 vancomycin-susceptible MRSA isolates recovered during 2006-08 and 2011-14. After an initial screening of hVISA using glycopeptide-supplemented agar strategies, the detection of hVISA was performed by Etest (GRD) and Macro-method (MET). Isolates deemed to be hVISA were subjected to population analysis profile/AUC (PAP/AUC) and WGS for further characterization. Finally, we interrogated alterations in predicted proteins associated with the development of the VISA phenotype in both hVISA and vancomycin-susceptible S. aureus (VSSA) genomes.<h4>Results</h4>A total of 39 MRSA isolates (3.3%) were classified as hVISA (1.4% and 5.6% in MRSA recovered from 2006-08 and 2011-14, respectively). Most of the hVISA strains (95%) belonged to clonal complex (CC) 5. Only 6/39 hVISA isolates were categorized as hVISA by PAP/AUC, with 6 other isolates close (0.87-0.89) to the cut-off (0.9). The majority of the 39 hVISA isolates exhibited the Leu-14→Ile (90%) and VraT Glu-156→Gly (90%) amino acid substitutions in WalK. Additionally, we identified 10 substitutions present only in hVISA isolates, involving WalK, VraS, RpoB and RpoC proteins.<h4>Conclusions</h4>The hVISA phenotype exhibits low frequency in Latin America. Amino acid substitutions in proteins involved in cell envelope homeostasis and RNA synthesis were commonly identified. Our results suggest that Etest-based methods are an important alternative for the detection of hVISA clinical isolates.","dates":{"release":"2020-01-01T00:00:00Z","publication":"2020 Sep","modification":"2022-02-10T15:43:52.723Z","creation":"2022-02-10T15:43:52.723Z"},"accession":"S-EPMC7443737","cross_references":{"pubmed":["32562543"],"doi":["10.1093/jac/dkaa221"]}}