Community-onset healthcare-associated MRSA bacteraemia in a district general hospital

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Epidemiology

Background:

• Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia presents a significant clinical challenge with high mortality and morbidity rates.
• A substantial proportion of MRSA bacteraemia cases occur within 72 hours of hospital admission, often linked to prior healthcare exposure.

Purpose of the Study:

• To analyze the characteristics, risk factors, and outcomes of MRSA bacteraemia episodes in a UK district general hospital.
• To identify key factors influencing mortality and inform strategies for improved patient management.

Main Methods:

• Retrospective analysis of 76 MRSA bacteraemia episodes over a four-year period.
• Data collection included patient demographics, comorbidities, clinical diagnoses, previous treatments, and acquisition risk factors.
• Mortality rates at 7 days and 3 months were assessed.

Main Results:

• The overall mortality rates at 7 days and 3 months were 31.5% and 53.4%, respectively.
• Common comorbidities included multiple chronic conditions and pneumonia; 10 patients died before targeted therapy initiation.
• Identified risk factors for MRSA infection included prior antibiotic use, advanced age, surgical ward/ICU admission, and presence of invasive devices (central venous catheters, urinary catheters).
• Nearly half of the episodes (48.7%) occurred in patients not previously known to be colonized with MRSA.

Conclusions:

• Patients with risk factors for MRSA should receive prompt empirical targeted therapy for staphylococci in blood cultures.
• Enhanced screening protocols may be necessary to reduce transmission and improve empirical antimicrobial therapy appropriateness.
• Community MRSA decolonization strategies could help decrease the incidence of community-onset healthcare-associated bacteraemias.