AUTHOR=Mišić Milena , Čukić Jelena , Vidanović Dejan , Šekler Milanko , Matić Sanja , Vukašinović Mihailo , Baskić Dejan 

TITLE=Prevalence of Genotypes That Determine Resistance of Staphylococci to Macrolides and Lincosamides in Serbia

JOURNAL=Frontiers in Public Health

VOLUME=Volume 5 - 2017

YEAR=2017

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2017.00200

DOI=10.3389/fpubh.2017.00200

ISSN=2296-2565

ABSTRACT=Macrolides, lincosamides and streptogramins (MLS) resistance genes are responsible for resistance to these antibiotics in Staphylococcus infections. The purpose of the study was to analyze the distribution of the MLS resistance genes in community- and hospital-acquired Staphylococcus isolates. The MLS resistance phenotypes (cMLSb, iMLSb, M/MSb, and LSa/b) were determined by double-disc diffusion method. The presence of the MLS resistance genes (ermA, ermB, ermC, msrA/B, lnuA, lnuB, and lsaA) were determined by end-point PCR in 179 isolates of staphylococci collected during one-year period at the Center for Microbiology of Public Health Institute in Vranje. The most frequent MLS phenotype among staphylococcal isolates, both community-acquired and hospital-acquired, was iMLSb (33.4%). The second most frequent was M/MSb (17.6%) with statistically significantly higher number of hospital-acquired staphylococcal isolates (p<0.05). MLS resistance was mostly determined by presence of msrA/B (35.0%) and ermC (20.8%) genes. Examined phenotypes was mostly determined by presence of one gene, especially by msrA/B (26.3%) and ermC (14.5%), but 15.6% was determined by a combination of two or more genes. M/MSb phenotype was the most frequently encoded by msrA/B (95.6%) gene, LSa/b phenotype by lnuA (56.3%) gene, and iMLSb phenotype by ermC (29.4%) and ermA (25.5%) genes. Although cMLSb phenotype was mostly determined by presence of ermC (28.9%), combinations of two or more genes have been present too. This pattern was particularly recorded in methicillin-resistant Staphylococcus aureus (MRSA) (58.3%) and methicyllin-resistant coagulase-negative Staphylococcus (MRCNS) (90.9%) isolates with cMLSB phenotype. The msrA/B gene and M/MSb phenotype were statistically significant higher in hospital-acquired than community-acquired staphylococci strains (p<0.05). There is no statistically significant differences between staphylococci harboring the rest of MLS resistance genes acquired in community and hospital settings (p>0.05). The prevalence of iMLSb phenotypes may change over time, so it is necessary to perform periodic survey of MLS resistance phenotypes, particularly where the D-test is not performed routinely.