title: Determination of antimicrobial resistance profile and inducible clindamycin resistance of coagulase negative staphylococci in pediatric patients: the first report from Iran.
abstract: BACKGROUND
  Currently, coagulase negative staphylococci (CoNS) have got much attention as a serious health problem especially in neonates and children. High incidence of antibiotic resistance, in particular methicillin resistance, has complicated the treatment of these organisms. The aim of this study is to determine the susceptibility to different antimicrobial agents and the prevalence of macrolideslincosamides-streptogramins B (MLSB) resistance in CoNS isolates obtained from pediatric patients.
  
  
  METHODS
  Totally 157 CoNS isolates from various clinical samples were examined for antibiotic resistance using disk diffusion and E-test methods. Double-disk test was applied to detect constitutive and inducible MLSB resistance (cMLSB and iMLSB) phenotypes.
  
  
  RESULTS
  Resistance to methicillin was seen in 98 (62.4%) isolates. All isolates were susceptible to vancomycin and linezolid. The prevalence of resistance to antibiotics tested was as follows: fusidic acid (n=58, 36.9%), gentamicin (n=73, 46.5%), ciprofloxacin (n=81, 51.6%), clindamycin (n=112, 71.3%), erythromycin (n=129, 82.2%) and trimethoprim/sulfamethoxazole (n=133, 84.7%). iMLSB phenotype was seen in 14 (8.9%) isolates, and 18 (11.5%) and 98 (62.4%) isolates showed MS and cMLSB phenotypes, respectively. We observed that high overall antibiotic resistance rates were associated significantly with methicillin resistance. Conversely, iMLSB phenotype was correlated neither with methicillin resistance nor with invasiveness.
  
  
  CONCLUSIONS
  Given the similarity observed between the prevalence of iMLSB and MS phenotypes, the performance of disk diffusion induction test is strongly recommended in our region.
authors.affiliation: Tabriz Research Center of Infectious and Tropical Diseases, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Aghazadeh
authors.forename: Reza
authors.initials: R
authors.lastname: Ghotaslou
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ahangarzadeh Rezaee
authors.forename: Mohammad Hassan
authors.initials: MH
authors.lastname: Moshafi
authors.forename: Zoya
authors.initials: Z
authors.lastname: Hojabri
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Saffari
mesh_terms: D002648:Child; D002675:Child, Preschool; D002981:Clindamycin / Q000494:pharmacology*; D003030:Coagulase / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D006776:Hospitals, Pediatric; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007492:Iran; D008826:Microbial Sensitivity Tests; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D013210:Staphylococcus / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification
chemical_list: D003030:Coagulase; D002981:Clindamycin