Phenotypes and genotypes of macrolide-resistant Streptococcus pneumoniae in Serbia

Abstract

Although macrolides are widely used for treating pneumococcal infections, an increase in macrolide resistance might compromise their use. The objective of this study was to determine the prevalence of macrolide-resistant phenotypes and genotypes in macrolide-resistant S. pneumoniae isolates in Serbia. A total of 228 macrolide-resistant strains isolated during the period of 2009-2012, were analyzed. Macrolide resistance phenotypes were determined by a double disk diffusion test. The presence of macrolide resistance genes was detected by PCR. Antibiotics susceptibilities were tested using the VITEK2 system and E test. Among the examined isolates, the MLSB phenotype which is linked to the presence of the erm(B) gene dominated (83.3%), while the mef(A) gene which is associated with the M phenotype, was identified in 16.7% isolates. Over 40% of isolates expressed co-resistance to penicillin. A multiple-resistant pattern was found in 36.4% strains, more frequently in children. However, all strains were susceptible to telithromycin, vancomycin, linezolid, fluoroquinolones and rifampicin. [Projekat Ministarstva nauke Republike Srbije, br. 175039]

The prevalence of resistance to macrolides and lincosamides among community- and hospital- acquired staphylococci and streptococci isolates in southeast Serbia

“…In our region, cMLSb phenotype was the most prevalent (38.2%) of all S. pneumoniae isolates from outpatient samples, whereas the M/MSb (33.3%) was dominant among hospital-acquired isolates. Different from our findings, authors from the Nišava district and central and northern parts of Serbia found that the dominant MLS resistance phenotype was cMLSb among hospital isolates of S. pneumoniae, but authors from Italy yielded results similar to our findings [22,23,25,26].…”

“…In our region, we discovered a very high resistance rate to erythromycin in S. pneumoniae (63.6%, 35/55 community-and 77.8%, 7/9 hospital-acquired isolates), which was in accordance with findings by Dinić et al [22] (78.4% and 65.6%, respectively). However, Hadnađev et al [23] and Mijač et al [4] found lower rate of resistance to erythromycin in S. pneumoniae (36% and 45%, respectively) in their studies in Serbia. Some parts of Malta and Romania had similar prevalence rate of macrolide resistance among S. pneumoniae in 2012 and 2015 to our findings.…”

Streptococcus pneumoniae serotype distribution in Vojvodina before the introduction of pneumococcal conjugate vaccines into the national immunization program

“…More than one third (36.4%) of pneumococcal isolates in Serbia in the 2009-2012 period expressed co-resistance to macrolides and penicillin. Multiresistant isolates were significantly more prevalent among children than adults [12].…”

Characterization of Streptococcus pneumoniae strains isolated from patients with meningitis before the introduction of pneumococcal conjugate vaccine in Serbia

“…Skoro četvrtina sojeva (~ 24%) bila je rezistentna na ≥ 3 antibiotika. Ovi rezultati su u skladu sa već objavljivanim podacima o rezistenciji S. pneumoniae na antibiotike u našoj zemlji, prema kojima su stope rezistencije tokom prve decenije 21. veka iznosile ~ 36% na penicilin i ~ 34% na eritromicin (16). Visoki nivoi rezistencije su zapaženi i u nekim drugim zemljama u okruženju.…”