[Daptomycin therapy in patients with bacteremia]

Abstract

Community-acquired bacteremias assciated with healthcare and, especially, those of nosocomial origin, are mainly caused by Gram-positive microorganisms. Notable among this group are Staphylococcus spp, with an incidence of methicillin resistance of approximately 30% in S. aureus and of 70% in coagulase-negative staphylococcus, which is higher in patients admitted to intensive care units. Vancomycin has been the most widely used antibiotic in these situations but its toxicity, especially in the kidney, and reports of failure when used for the treatment of methicillin-resistant S. aureus (MRSA) and with a vancomycin MIC > 1 mg/L have led to the search for other treatments. Daptomycin is a new lipopeptide antibiotic that has been shown to be not inferior to vancomycin in a pivotal clinical trial in patients with bacteremia and right endocarditis due to S. aureus. Recent guidelines and consensus documents place daptomycin as an ideal alternative in these situations, indicating its use in MRSA bacteremia with a vancomycin MIC > 1 mg/L, as well as in patients whose renal dysfunction excludes the use of vancomycin therapy. Evidence of worse prognosis in MRSA bacteremia when empirical treatment is inappropriate has led to the recommendation of daptomycin as the first-choice drug in critically ill patients with suspected Gram-positive bacteremic infection and renal dysfunction and/or in hospitals where there is a high prevalence of MRSA with a MIC > 1 mg/L. The recommended dose in severely ill patients should be higher than 6 mg/kg/day.