Methicillin-resistant Staphylococcus aureus development in intensive care patients: A case-control study

OBJECTIVES: To determine the factors associated with the development of methicillin-resistant Staphylococcus aureus (MRSA), hospital stay and mortality, and early versus late MRSA infection. METHODS: Cases (n=44) were intensive care unit (ICU) patients admitted to King Fahd Specialist Hospital, Al-Qassim, Saudi Arabia between 2015 and 2019 who developed MRSA during their hospital stay. Controls (n=48) were patients from the same place and period who did not develop MRSA. Data were abstracted from hospital records. RESULTS: Admission with sepsis (case: 46% vs. control: 2%, p<0.001) and having at least one comorbid condition (case: 95% vs. control: 46%, p<0.001) were significantly associated with the development of MRSA. Age (mean ± SD: case: 65±18, control: 64±18, p=0.7) and gender (% male, case: 52%, control: 56%, p=0.70) were not associated with the development of MRSA. Approximately 73% of all MRSA cases developed within the first 2 weeks of admission. Among the early cases, 44% died during their ICU stay; the corresponding percentage among the late cases was 42% (p=0.69). There was no difference between early and late MRSA cases in terms of non-sepsis admissions (50% vs. 67%, p=0.32) or comorbid status (at least one: 97% vs. 92%, p=0.17). CONCLUSION: Sepsis and comorbid conditions were significant risk factors for MRSA development among hospital patients.