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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
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Back to the Future: Penicillin-Susceptible Staphylococcus aureus
Matthew P Cheng1, Pierre René1, Alexandre P Cheng2
1Division of Infectious Diseases and Department of Medical Microbiology, McGill University Health Centre, Montréal, Quebec, Canada.
The American Journal of Medicine
|March 1, 2016
Summary
Penicillin resistance in Staphylococcus aureus bacteremia is decreasing. Over a quarter of methicillin-susceptible Staphylococcus aureus (MSSA) infections were susceptible to penicillin, suggesting it may be a viable treatment option.
Area of Science:
- Infectious Diseases
- Clinical Microbiology
- Antimicrobial Resistance
Background:
- Penicillin resistance in Staphylococcus aureus emerged rapidly following widespread use.
- Recent trends suggest a potential resurgence in penicillin susceptibility.
- Methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia represents a significant clinical challenge.
Purpose of the Study:
- To quantify the prevalence of penicillin resistance in MSSA bacteremia.
- To evaluate the susceptibility patterns of MSSA to other common antibiotics.
Main Methods:
- Retrospective review of adult MSSA bacteremia cases from April 2010 to April 2015.
- Antibiotic susceptibility testing for penicillin, erythromycin, clindamycin, and trimethoprim-sulfamethoxazole (TMP-SMX).
- Analysis of patient demographics, treatment outcomes, and associations with antibiotic resistance.
Main Results:
- Out of 324 MSSA bacteremia episodes, 28% of isolates were susceptible to penicillin.
- High susceptibility rates were observed for TMP-SMX (98%), clindamycin (74%), and erythromycin (71%).
- Penicillin resistance was associated with erythromycin resistance, but not with ICU admission or mortality.
Conclusions:
- A significant proportion of MSSA bacteremia cases remain susceptible to penicillin.
- Parenteral penicillin may be a suitable treatment option, potentially offering pharmacokinetic benefits.
- Further investigation into penicillin's role in treating MSSA infections is warranted.
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