Methicillin-resistant Staphylococcus aureus in a surgical intensive care unit

Area of Science:

• Infectious Diseases
• Critical Care Medicine
• Public Health

Background:

• Rising rates of methicillin-resistant Staphylococcus aureus (MRSA) infections, particularly community-associated MRSA (CA-MRSA), are a significant public health concern.
• The prevalence and impact of MRSA, including CA-MRSA, in critically ill trauma patients remain incompletely understood.

Purpose of the Study:

• To determine the prevalence of MRSA infections in trauma patients admitted to the surgical intensive care unit (SICU).
• To differentiate between hospital-acquired MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections in this population.
• To analyze the clinical outcomes, including mortality, hospital charges, and length of stay, associated with MRSA infections in trauma patients.

Main Methods:

• Retrospective review of a SICU database from April 2003 to April 2007.
• Inclusion criteria: trauma patients surviving 48 hours or more with positive culture results during SICU stay.
• Assessment of 582 patients and 2,860 cultures for MRSA, with differentiation of CA-MRSA and HA-MRSA.

Main Results:

• MRSA was detected in 36 of 582 patients (6.2%), with 368 positive cultures (12.9%).
• Thirteen patients (2.2% of total patients) met criteria for CA-MRSA infection.
• No significant difference in mortality or hospital charges was observed between MRSA and non-MRSA infections.
• Patients with HA-MRSA infections experienced significantly longer hospital lengths of stay compared to CA-MRSA patients (42.7 vs. 25.3 days, P=0.037).

Conclusions:

• MRSA represents a substantial infectious threat in critically ill trauma patients.
• CA-MRSA may be playing an increasingly significant role in the pathogenesis of infections within this vulnerable patient group.
• While not impacting mortality, MRSA infections, particularly HA-MRSA, are associated with prolonged hospitalizations.