Prevalence and Molecular Determinants of Antimicrobial Resistance in Clinical Isolates of Staphylococcus haemolyticus from India

Abstract

Aims: Although Staphylococcus haemolyticus is considered as a part of normal skin flora, infections associated with them are increasing. Irrespective of the low virulence profile it poses a severe threat to patients with indwelling devices due to its multidrug-resistant nature. The aim of this study was to determine antibiotic resistance patterns and to detect the genes responsible in clinical isolates of S. haemolyticus. Results: All the 356 S. haemolyticus isolates were susceptible to glycopeptides. 91.3% were resistant to cefoxitin, 85.4% to erythromycin, 57.3% to co-trimoxazole, 52.8% to clindamycin, whereas only 3.7% of isolates were resistant to linezolid. Tetracycline resistance was found in 16.6% of isolates with tetK as the major genetic determinant. Most of the cefoxitin-resistant isolates carried mecA gene (99.4%), whereas dfrG gene was found only in 57.3% of co-trimoxazole-resistant isolates. Macrolides resistance was seen in 85.4% of isolates with cMLS B (constitutive macrolide, lincosamide, and streptogramin B) (42.5%) as the major phenotype with ermC and msrAB genes as the predominant genetic determinants. Among linezolid-resistant isolates all except one showed higher minimum inhibitory concentration (MIC) (>256 mg/mL) with chloramphenicol-florfenicol resistance (cfr) gene as the genetic determinant, whereas one isolate had a lower MIC (16 mg/mL) and was negative for cfr gene. Conclusion: Emerging resistance to linezolid is a cause for concern. Strategies to prevent the spread of antibiotic resistance require continuous surveillance of these multidrug-resistant strains.

Clinical Infections, Antibiotic Resistance, and Pathogenesis of Staphylococcus haemolyticus

“…They found that 95% of the isolates were resistant to penicillin and ampicillin and 88% of the isolates were resistant to oxacillin and cefoxitin [80]. Similarly, Manoharan et al recorded that the susceptibility of 356 clinical isolates of S. haemolyticus to cefoxitin and penicillin was very low, 8.7% and 5.9%, respectively [81]. Likewise, De Vecchi et al showed that S. haemolyticus, isolated from joint infections, have the highest level of oxacillin resistance (83%), compared to S. aures and other CoNS species isolated from the same patients [82].…”

Vancomycin Heteroresistance in Staphylococcus Haemolyticus : Elusive Phenotype

“…Interpretation was carried out according to the CLSI guidelines [ 18 ]. Isolates resistant to at least one agent in each of three or more classes of antimicrobials were classified as MDR [ 19 ].…”

Antibiotic Resistance in Bacteria—A Review

“…The first or latest cases of antibiotic resistance of chosen foodborne pathogens in different parts of the world. References [ 257 , 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 , 269 , 270 , 271 , 272 , 273 , 274 , 275 , 276 , 277 , 278 , 279 , 280 , 281 , 282 , 283 , 284 , 285 , 286 , 287 , 288 , 289 , 290 , 291 , 292 , 293 , 294 , 295 , 296 , 297 , 298 , 299 , 300 , 301 , 302 ] are cited in the Supplementary Materials.…”