Prevalence of methicillin resistance and superantigenic toxins in Staphylococcus aureus strains isolated from patients with cancer.

BACKGROUND

This study aimed to determine the frequency of methicillin-resistant Staphylococcus aureus (MRSA), antibiotic resistance patterns, superantigenic toxins profile, and clonality of this pathogen in patients with cancer.

RESULTS

In total, 79 (25.7%) isolates were confirmed as Staphylococcus species, from which 38 (48.1%) isolates were S. aureus, and 29 (76.3%) isolates were confirmed as MRSA. The highest resistance in MRSA strains was seen against ciprofloxacin (86.2%) and erythromycin (82.8%). Teicoplanin, and linezolid were the most effective antibiotics. From all MRSA isolates, 3 strains (10.3%) were resistant to vancomycin with minimum inhibitory concentration values of 128 μg/ml. The prevalence of superantigenic toxins genes was as follows: pvl (10.5%), tsst-1 (36.8%), etA (23.7%), and etB (23.7%). The t14870 spa type with frequency of 39.5% was the most prevalent clone type circulating in the cancer patients.

CONCLUSIONS

This study showed the circulating of spa t14870 as the most predominant MRSA clone in cancer patients of southwest Iran. Also, a diverse antibiotic resistance pattern and toxin profiles were seen among MRSA isolates.