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Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is considered a major cause of healthcare-associated (HA) and community-acquired (CA) infections. Considering non-β-lactam susceptibility as a potential marker for mecC-MRSA and CA-MRSA, the aim of this study was to determine the frequency and the associated genetic lineages of non-beta-lactam-antibiotic susceptible MRSA (NBLS-MRSA) strains in a multicenter study in Spain., Methods: A collection of 45 NBLS-MRSA strains recovered in the period from January to June 2016 from 12 Spanish hospitals was analyzed. Molecular typing through spa-type characterization, agr group and multi-locus-sequence typing was performed. Methicillin-resistant genes (mecA and mecC) as well as immune evasion cluster (scn-chp-sak-sea-sep, considering scn gene as the marker of IEC system) and Panton-Valentine leukocidin (PVL) genes were determined with PCR/sequencing., Results: The NBLS-MRSA phenotype was uncommon in the 12 hospitals analyzed (NBLS-MRSA/MRSA frequency: 0.3%-7.7%). All strains contained the mecA gene (and none contained mecC). Twenty-two different spa-types were detected among NBLS-MRSA strains, with spa-t008/agr-I the most prevalent (27%). The main clonal complexes were (CC/%): CC8/42.2%, CC5/33.3% and CC30/4.4%, with ST8 and ST5 as the main sequence types. The PVL toxin was present in 38% of strains (with spa-types t008, t024, t019, t044, t068, t318 and t3060). The IEC genes were detected in 78% of strains: IEC type-B (n=17), type-F (n=16), type-A (n=1) and type-E (n=1); 10 MRSA isolates were scn-negative., Conclusion: The NBLS-MRSA phenotype is uncommon in the analyzed hospitals; although no mecC-positive strains were detected, it could be a good marker for MRSA PVL-positive isolates (38%), frequently associated with CA-MRSA infections., (Copyright © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates producing the Panton-Valentine leukocidin (PVL) have been reported worldwide. We describe the molecular characteristics of PVL-positive CA-MRSA strains isolated in Madrid, Spain, and analyze the clinical features of patients infected with these isolates. From 2004 to 2007, we collected 13 PVL-positive MRSA isolates from patients attending to the emergency department. The isolates were genotyped by pulsed-field gel electrophoresis, SCCmec typing, agr polymorphism, and multilocus sequence typing. Susceptibility to 29 antimicrobials was determined by the broth microdilution and by the E-test methods. The isolates belonged to 3 genotypes: ST8-SCCmec IVc (n = 11), ST5-SCCmec IVa (n = 1), and ST80-SCCmec IVc (n = 1). The corresponding agr types were I, II, and III, respectively. Five isolates were resistant to tetracycline and doxycycline, and 1 was resistant to fusidic acid (ST80). The isolates were from children (n = 9) and adults (n = 4), and were associated with skin and soft tissue infections (n = 9), otitis (n = 1), and bacteremia (n = 1). Nine patients were from South America. Our results indicate the transcontinental importation and recent emergence in Spain of PVL-positive CA-MRSA strains belonging to 3 distinct lineages, including 1 predominant (ST8-SCCmec IVc).