Clinical outcome of combination of vancomycin and ceftaroline versus vancomycin monotherapy for treatment of methicillin resistant Staphylococcus aureus bloodstream infection.

BACKGROUND

The role of combination therapies for serious methicillin-resistant Staphylococcus aureus (MRSA) infections is widely debated.

METHODS

This retrospective cohort study included adults with MRSA bacteraemia treated between January 1, 2013, to December 31, 2022. Patients receiving combination therapy with vancomycin and ceftaroline were matched in a 2:1 ratio with those on vancomycin monotherapy based on bacteraemia source and illness severity. The primary outcome was frequency of bacteraemia recurrence. Secondary outcomes were all cause 30/90-day mortality, recurrence or mortality at 30/90 days and in hospital length of stay.

RESULTS

Of 57 patients included, 37 (65%) were in the combination group. The overall intensive care unit admission rate was 63.2% (36/57) and the Pitt Bacteraemia Score was 1 [0-4] at the time of diagnosis. The most common source of infection was endovascular/endocarditis (n = 36, 63.2%). Demographic and clinical characteristics were similar between the monotherapy and combination group of patients, except for higher body mass index (32.5 [25.5-36.4] vs. 24.4 [20.9-29], p = 0.004) and a greater immunosuppression prevalence (3 (15%) vs. 0 (0%), p = 0.039) in monotherapy group. There was no significant difference in bacteraemia recurrence (3 (15%) vs. 4 (10.8%), p = 0.7) or all-cause 30-day mortality (3 (15%) vs. 4 (10.8%), p = 0.7) between the two groups.

CONCLUSION

The results of this study are limited by a retrospective observational design; however, combination of vancomycin and ceftaroline for MRSA bacteraemia was not associated with lower bacteraemia recurrence or mortality compared to vancomycin monotherapy.