Emerging variants of methicillin-resistant Staphylococcus aureus genotypes in Kuwait hospitals

Samar S Boswihi; Edet E Udo; Stefan Monecke; Bindu Mathew; Bobby Noronha; Tina Verghese; Sajida B Tappa

doi:10.1371/journal.pone.0195933

Emerging variants of methicillin-resistant Staphylococcus aureus genotypes in Kuwait hospitals

PLoS One. 2018 Apr 18;13(4):e0195933. doi: 10.1371/journal.pone.0195933. eCollection 2018.

Authors

Samar S Boswihi¹, Edet E Udo¹, Stefan Monecke^{2

3

4}, Bindu Mathew¹, Bobby Noronha¹, Tina Verghese¹, Sajida B Tappa¹

Affiliations

¹ Department of Microbiology, Faculty of Medicine, Kuwait University. Jabriya, Kuwait.
² Alere Technologies GmbH, Jena, Germany.
³ InfectoGnostics Research Campus, Jena, Germany.
⁴ Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Dresden, Germany.

Abstract

Background: Frequent changes in the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) occurring worldwide demand regular surveillance to study their composition and distribution in healthcare facilities. We investigated the genotypic characteristics of MRSA obtained in Kuwait hospitals to better understand their clonal distribution.

Materials and methods: A total of 1,327 MRSA isolates obtained from clinical samples in 13 Kuwait hospitals from 1 January to 31 December 2016 were investigated using antibiogram, SCCmec typing, spa typing and DNA microarray.

Results: The isolates belonged to six SCCmec types with the majority belonging to type IV (658; 49.5%) and type V (355; 26.7%). Two hundred and sixty-one spa types were identified with spa types t688, t304, t860, t127, t044, t311, t002, t223, t267, t019, t3841, t005, t084, t852, and t657 constituting 51.0% (n = 677) of the isolates. Among the 1,327 MRSA isolates, 102 (7.68%) isolates were identified as novel variants of internationally recognized MRSA clones. These 102 isolates were investigated further and belonged to 14 clonal complexes (CCs) with CC361 (32; 32.3%), CC30 (15; 14.7%), CC22 (13; 12.7%) and CC1 (11, 10.7%) as the dominant CCs. Eighty-one (79.4%) of the novel isolates harbored SCCmec IV or V+fusC composite genetic elements. Four isolates (3.9%) harbored unusual combinations of ccr and mec complexes comprising of CC6-MRSA [IV+fusC+ccrC], CC97-MRSA [V/VT+fusC+ccrAB2], CC121-MRSA [V/VT+fusC+ccrB4] and CC1-MRSA-pseudoSCCmec [class B mec+fusc+ccrAB1]. Forty-six (45.1%) of these isolates were positive for PVL and 89 (87.2%) were resistant to fusidic acid mediated by fusC.

Conclusions: The study showed the emergence of novel variants of previously recognized MRSA genotypes with unusual genetic characteristics including high prevalence of PVL and fusidic acid resistance in Kuwait hospitals. This has added to the dynamic lists of known variations in MRSA genomes which can impose serious challenges for infection control and treatment of MRSA infections.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cross Infection*
Genes, Bacterial
Genetic Variation*
Genotype*
Hospitals
Humans
Kuwait / epidemiology
Methicillin-Resistant Staphylococcus aureus / classification*
Methicillin-Resistant Staphylococcus aureus / genetics*
Multilocus Sequence Typing
Staphylococcal Infections / epidemiology*
Staphylococcal Infections / microbiology*
Virulence / genetics

Grants and funding

This work was funded by Research Sector, Kuwait University Grant no. YM02/12 to SSB. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.