Predominance of a methicillin-resistant Staphylococcus aureus clone susceptible to erythromycin and several other non-β-lactam antibiotics in a Greek hospital

A clone of heterogeneously methicillin-resistant Staphylococcus aureus (MRSA) isolates susceptible to erythromycin, ciprofloxacin, clindamycin, co-trimoxazole, nitrofurantoin, rifampicin, tetracycline and vancomycin, predominated in a Greek hospital with a high incidence of MRSA, representing 69.1% of the total MRSA isolates. All isolates of this clone lacked the conserved genes ermA and aadD. Two subtypes of this clone were detected, the more common being resistant to aminoglycosides and carrying the bi-functional gene aacA-aphD, while an aminoglycoside-susceptible variant, lacking this gene, lost a larger Smal macrorestriction DNA fragment and gained a smaller fragment.