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Is methicillin-resistant Staphylococcus aureus pneumonia epidemiology and sensitivity changing?

Elsi Diaz1, Imelyn M Fernandez, Lohengrin Jimenez

  • 1Christus Spohn Memorial Hospital, Corpus Christi, Texas, USA.

The American Journal of the Medical Sciences
|August 6, 2011
PubMed
Abstract

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a growing threat. While resistance to clindamycin is increasing, trimethoprim/sulfamethoxazole (TMP/SMX) remains effective against both community- and hospital-acquired MRSA pneumonia.

Area of Science:

  • Infectious Diseases
  • Pulmonology
  • Clinical Microbiology

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia presents a significant and evolving threat due to high resistance and virulence.
  • The rapid changes in MRSA pneumonia epidemiology and antibiotic sensitivity highlight its potential to become a
  • super bug
  • .

Purpose of the Study:

  • To evaluate the incidence of community-acquired (CA-MRSA) and hospital-acquired (HA-MRSA) pneumonia at Christus Spohn.
  • To assess the antibiotic susceptibility patterns of MRSA pneumonia in this patient population.

Main Methods:

  • Retrospective analysis of inpatient charts from Christus Spohn Memorial Hospital (2006-2008).
  • Patient selection based on positive MRSA sputum cultures and adherence to CDC, ATS, and IDSA guidelines.
  • Categorization into CA-MRSA and HA-MRSA pneumonia groups.

Main Results:

  • Increased resistance to clindamycin was observed in both CA-MRSA and HA-MRSA isolates.
  • Trimethoprim/sulfamethoxazole (TMP/SMX) demonstrated preserved sensitivity against both CA-MRSA and HA-MRSA.

Conclusions:

  • Clindamycin resistance in MRSA pneumonia has risen over time.
  • TMP/SMX maintains its efficacy against MRSA, suggesting it should be reconsidered as a treatment option.
  • TMP/SMX is a viable therapeutic choice for both CA-MRSA and HA-MRSA pneumonia, particularly CA-MRSA.

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