Cryptic resistance in Staphylococcus aureus: a risk for the treatment of skin infection?

Purpose of reviewThe purpose of this review is to explore major challenges that face routine diagnostic laboratories in detecting cryptic (hidden) antibiotic resistances in Staphylococcus aureus and the impact of these covert resistances in the management of skin and soft tissue infections.Recent findingsThe review covers recent literature and works regarding a number of evolving mechanisms and forms of antibiotic resistances in S. aureus, including novel oxacillin-susceptible-mecA-positive meticillin-resistant S. aureus (OS-MRSA) strains and MRSA isolates that harbour a divergent mecA homologue termed mecC within the novel staphylococcal cassette chromosome mec XI element.SummaryS. aureus strains causing skin and soft tissue infections are evolving with regard to virulence as well as antimicrobial resistance. Cryptic resistances continue to escape routine diagnostic tests. This means that there are still many unknowns regarding their global dissemination, virulence, threats in clinical practice and optimal treatment strategies. Larger studies are needed to further understand the pathogenic consequences of cryptic resistances in S. aureus in skin and soft tissue infections, which may ultimately provide novel preventive or treatment approaches for this significant human pathogen.