Staphylococcus aureus bacteremia (SAB) is characterized by a high incidence of bacterial complications, including distant metastatic foci, local extension, and relapses, with a crude mortality that ranges from 20 to 40%. Unlike other infectious diseases and despite the existence of effective oral agents with high bioavailability, current guidelines do not contemplate oral switch due to the lack of sound clinical evidence. The authors explored the efficacy of early switch to oral linezolid in patients with low risk SAB in relation to standard therapy. High risk SAB as defined by the authors included persistence of positive blood cultures after ≥3 days of appropriate treatment (including source control), development of septic thrombophlebitis, infective endocarditis, infected arterial aneurysm, endovascular graft infection, or other metastatic distant foci before concluding parenteral therapy, and/or any device-related infection where the device could not be removed in the first 3 days and osteoarticular infections.
After propensity score matching, the authors included 45 patients of the linezolid group and 90 patients of the SPT group. Leading SAB-sources were catheter-related (49.6%), unknown origin (20.0%), and skin and soft tissue (17.0%). Patients in the linezolid group had less chronic renal disease (4.4% vs 22.2%). They observed no difference in 90-day relapse between the linezolid group and the SPT group (2.2% vs 4.4% respectively; P=0.87). No statistically significant difference was observed in 30-day all-cause mortality between the linezolid group and the SPT group (2.2% vs 13.3%; P=0.08). The median length of hospital stay after onset was 8 days in the linezolid group and 19 days in the SPT group (P<0.01). No drug-related events leading to discontinuation were noted in the linezolid group.
The authors propose that linezolid is an effective and safe option allowing early hospital discharge in patients with low risk SAB. This findings likely require validation in a randomized trial before translation to regular clinical practice.