Human cathelicidin LL-37 resistance and increased daptomycin MIC in methicillin-resistant Staphylococcus aureus strain USA600 (ST45) are associated with increased mortality in a hospital setting.
Sakoulas. George G; Guram. Kripa K; Reyes. Katherine K; Nizet. Victor V; Zervos. Marcus M
Key Findings
- USA600 MRSA is more resistant to killing by the human peptide LL-37 than other MRSA strains.
- The same strain shows increased minimum inhibitory concentrations (MIC) for daptomycin, indicating growing antibiotic resistance.
- Patients infected with USA600 MRSA have higher mortality rates in clinical settings.
Practical Outcomes
- For most biohackers and self‑experimenters, this research offers limited direct action. It highlights that certain bacterial infections can become harder to treat due to combined immune‑peptide and antibiotic resistance, underscoring the importance of infection prevention and prudent antibiotic use.
Summary
The study found that a specific MRSA strain (USA600) is better at surviving attacks from the human immune peptide LL-37 and also shows higher resistance to the antibiotic daptomycin, which together are linked to higher death rates in hospitals.
Abstract
Bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) USA600 has been associated with increased patient mortality. We found that USA600 MRSA exhibited significantly increased resistance to human cathelicidin LL-37 killing and daptomycin MIC creep compared to non-USA600 MRSA. Virulent health care-associated MRSA strains may coevolve innate host defense peptide and antibiotic resistances.
Study Information
pubmed
2014
2014-03-19T00:00:00.000Z
10.1128/jcm.00189-14