From the Guidelines
Vancomycin is the recommended first-line antibiotic for treating Staphylococcus aureus bloodstream infections in dialysis patients, with a dosing regimen of 15-20 mg/kg after dialysis sessions and target trough levels of 15-20 μg/mL for serious infections. The treatment duration is generally 4-6 weeks for uncomplicated bacteremia. Alternative options include daptomycin (6-8 mg/kg after dialysis) if the patient has MRSA or vancomycin intolerance, and cefazolin (20 mg/kg after dialysis) may be used for methicillin-sensitive S. aureus 1. It's essential to monitor renal function and adjust the antibiotic regimen accordingly, as dialysis patients are at higher risk of complications and altered drug clearance 1. Blood cultures should be repeated to confirm clearance of infection, and the dialysis access site should be evaluated as a potential source of infection, possibly requiring catheter removal if it's the suspected source. Antibiotic selection may need adjustment based on susceptibility testing results and clinical response.
Some key considerations for dialysis patients include:
- Monitoring vancomycin trough levels to ensure adequate therapy and minimize the risk of nephrotoxicity 1
- Adjusting the dosing regimen based on the patient's renal function and dialysis schedule 1
- Considering alternative antibiotics, such as daptomycin or cefazolin, in cases of vancomycin intolerance or resistance 1
- Evaluating the dialysis access site as a potential source of infection and removing the catheter if necessary 1
Overall, the treatment of Staphylococcus aureus bloodstream infections in dialysis patients requires careful consideration of the patient's renal function, dialysis schedule, and antibiotic regimen to ensure optimal outcomes and minimize the risk of complications.
From the FDA Drug Label
2.6 Dosage in Patients with Renal Impairment Adult Patients: No dosage adjustment is required in adult patients with creatinine clearance (CL CR) greater than or equal to 30 mL/min The recommended dosage regimen for daptomycin for injection in adult patients with CL CR less than 30 mL/min, including adult patients on hemodialysis or continuous ambulatory peritoneal dialysis (CAPD), is 4 mg/kg (cSSSI) or 6 mg/kg ( S. aureus bloodstream infections) once every 48 hours When possible, daptomycin for injection should be administered following the completion of hemodialysis on hemodialysis days
The best antibiotic for a dialysis patient with Staph aureus positive blood culture is daptomycin.
- The recommended dosage is 6 mg/kg once every 48 hours for S. aureus bloodstream infections in adult patients with creatinine clearance less than 30 mL/min, including those on hemodialysis.
- It is recommended to administer daptomycin following the completion of hemodialysis on hemodialysis days 2.
From the Research
Treatment Options for Staph Aureus Positive Blood Culture in Dialysis Patients
- Vancomycin is commonly used as empiric therapy for methicillin-resistant S. aureus bacteremia in hemodialysis patients, with a recommended target serum concentration of 10 µg mL-1 to avoid resistance 3.
- However, subtherapeutic concentrations of vancomycin can lead to decreased susceptibility to vancomycin and daptomycin, increased S. aureus survival to whole blood bactericidal action, and strain-dependent biofilm production 3.
- Mupirocin has been shown to be effective in reducing the risk of S. aureus bacteremia in hemodialysis patients, particularly when applied intranasally or at the catheter exit site 4.
Comparative Effectiveness of Antibiotics
- A systematic review and meta-analysis found that vancomycin had a lower microbiological cure rate and clinical cure rate compared to daptomycin, as well as more adverse events 5.
- However, another study found that switching to daptomycin within 3 days of initial receipt of vancomycin was associated with lower 30-day mortality among patients with MRSA bloodstream infections 6.
- The efficacy of vancomycin in treating Staphylococcus aureus bacteraemia is still excellent, but slightly inferior in adverse events, and daptomycin is expected to be a better antimicrobial drug 5.
Follow-up Blood Cultures
- Follow-up blood cultures (FUBCs) should be performed to manage the infection properly and prevent SAB relapse, even if a patient has a single S. aureus-positive blood culture and no fever 7.
- The rate of positivity of FUBCs was significantly higher in methicillin-resistant S. aureus (MRSA) than in methicillin-susceptible S. aureus, and relapse of SAB was significantly more frequent in patients in whom FUBCs were not performed 7.