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Background and Objectives: The ever-increasing of antibiotic resistance in methicillin-resistant Staphylococcus aureus (MRSA) has become a major threat to public health worldwide. Molecular typing is used to determine the source of MRSA infections as well as to control and prevent the spread of these pathogens. The present study aimed to investigate the char- acteristics of staphylococcal cassette chromosome mec (SCCmec) types and antibiotic resistance of community- acquired (CA-) and hospital acquired (HA-) MRSA isolates. Materials and Methods: In this cross-sectional study, the antibiotic susceptibility patterns of 109 clinical S. aureus isolates were determined by the Kirby-Bauer disk-diffusion and microdilution broth methods. MRSA isolates were confirmed using the polymerase chain reaction (PCR) method for the detection of the mecA gene. SCCmec typing was performed by a mul- tiplex PCR assay among MRSA isolates. Results: The prevalence of MRSA isolates was 39.4%. Linezolid, vancomycin, and ceftaroline were the most effective agents against MRSA isolates. The incidence of multidrug-resistant (MDR) and resistance to most antibiotics were signifi- cantly higher in MRSA than methicillin-susceptible S. aureus (MSSA) isolates (P

Background and Objectives: Non-fermentative Gram-negative Bacilli (NFGNB) is known as a major cause of health- care-associated infections with high levels of antibiotic resistance. The aim of this study was to investigate the antibiotic resistance profiles and molecular characteristics of metallo-beta-lactamase (MBL)-producing NFGNB. Materials and Methods: In this cross-sectional study, the antibiotic resistance profile of 122 clinical NFGNB isolates was determined by the Kirby-Bauer disk diffusion and microdilution broth methods. Bacterial isolates were investigated for the detection of MBLs production using the combination disk diffusion Test (CDDT). The existence of bla , bla , and bla NDM genes in all carbapenem-resistant isolates was determined employing polymerase chain reaction (PCR) assays. Results: High resistance in Pseudomonas aeruginosa was reported to cefotaxime and minocycline, whereas Acinetobacter baumannii isolates were highly resistant to all antibiotics except colistin. Multidrug resistance (MDR)-NFGNB (66% vs. 12.5%, P=0.0004) and extensively drug resistant (XDR)-NFGNB (55.7% vs. 12.5%, P=0.001) isolates were significantly more common in hospitalized patients than in outpatients. The production of MBL was seen in 40% of P. aeruginosa and 93.3% of A. baumannii isolates. It was found that 33.3% and 46.7% of carbapenem-resistant P. aeruginosa isolates, and 13.3% and 28.9% of carbapenem-resistant A. baumannii isolates were harboring bla IMP-1 and bla VIM-1 genes, respectively. The incidence of MDR (98.2% vs. 28.3%, P