Daptomycin versus vancomycin for osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA): a nested case-control study.

Vancomycin is the standard antibiotic for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. While daptomycin is approved for MRSA bacteremia, its effectiveness in osteoarticular infections (OAIs) has not been established. A 1:2 nested case-control study of adult patients with MRSA OAIs admitted to an academic center from 2005 to 2010 was carried out. Clinical outcomes and drug toxicity in patients treated with daptomycin versus vancomycin were compared. Twenty patients with MRSA OAIs treated with daptomycin were matched to 40 patients treated with vancomycin. The median age of the patients was 52 years (range, 25-90), and 40 (67%) were male. Most patients had osteomyelitis (82%), predominantly from a contiguous source (87%). Forty percent were diabetics. Diabetic patients were more likely to receive vancomycin than daptomycin [20 (50%) vs. 4 (20%); p = 0.03]. Vancomycin was more often combined with antibiotics other than daptomycin [22 (55%) vs. 5 (25%); p = 0.03]. The median total antibiotic treatment duration was 48 (daptomycin) vs. 46 days (vancomycin) (p = 0.5). Ninety percent of daptomycin-treated patients had previously received vancomycin for a median of 14.5 days (range, 2-36). Clinical success rates were similar between daptomycin and vancomycin at 3 months [15 (75%) vs. 27 (68%); p = 0.8] and 6 months [14 (70%) vs. 23 (58%); p = 0.5], even after propensity score-based adjustment for antibiotic assignment. The frequency of adverse events was similar between treatment groups [1 (5%) vs. 7 (18%); p = 0.2]. Daptomycin and vancomycin achieved similar rates of clinical success and drug tolerability. Daptomycin is a reasonable alternative for treating MRSA OAIs, particularly in patients where therapy with vancomycin has not been well tolerated.

Vancomycin resistance has no influence on outcomes of enterococcal bacteriuria.

BACKGROUND: Infections with vancomycin-resistant enterococci (VRE) are a growing concern in hospitals. The impact of vancomycin resistance in enterococcal urinary tract infection is not well-defined. AIM: To describe the epidemiology of enterococcal bacteriuria in a hospital and compare the clinical picture and patient outcomes depending on vancomycin resistance. METHODS: This was a 6-month prospective cohort study of hospital patients who were admitted with or who developed enterococcal bacteriuria in a 1250-bed tertiary care hospital. We examined clinical presentation, diagnostic work-up, management, and outcomes. FINDINGS: We included 254 patients with enterococcal bacteriuria; 160 (63%) were female and median age was 65 years (range: 17-96). A total of 116 (46%) bacteriurias were hospital-acquired and 145 (57%) catheter-associated. Most patients presented with asymptomatic bacteriuria (ASB) (119; 47%) or pyelonephritis (64; 25%); 51 (20%) had unclassifiable bacteriuria and 20 (8%) had cystitis. Secondary bloodstream infection was detected in 8 (3%) patients. Seventy of 119 (59%) with ASB received antibiotics (mostly vancomycin). There were 74 (29%) VRE bacteriurias. VRE and vancomycin-susceptible enterococci (VSE) produced similar rates of pyelonephritis [19 (25%) vs 45 (25%); P = 0.2], cystitis, and ASB. Outcomes such as ICU transfer [10 (14%) VRE vs 17 (9%) VSE; P = 0.3], hospital length of stay (6.8 vs 5.0 days; P = 0.08), and mortality [10 (14%) vs 13 (7%); P = 0.1] did not vary with vancomycin susceptibility. CONCLUSIONS: Vancomycin resistance did not affect the clinical presentation nor did it impact patient outcomes in this cohort of inpatients with enterococcal bacteriuria. Almost half of our cohort had enterococcal ASB; more than 50% of these asymptomatic patients received unnecessary antibiotics. Antimicrobial stewardship efforts should address overtreatment of enterococcal bacteriurias.