From the Guidelines
For methicillin-sensitive Staphylococcus aureus (MSSA) peritoneal dialysis catheter-associated peritonitis, the antibiotic of choice is cefazolin or a first-generation cephalosporin administered intraperitoneally. The typical dosing regimen is cefazolin 15-20 mg/kg in a single daily exchange with a dwell time of at least 6 hours, or continuous dosing with 500 mg per 2-liter bag in each exchange. Treatment should continue for 14-21 days, with duration depending on clinical response. Vancomycin should be reserved for patients with beta-lactam allergies. It's crucial to obtain cultures before starting antibiotics and to reassess therapy based on culture results and clinical improvement. Catheter removal may be necessary if there is no improvement within 5 days, if there are recurrent episodes, or if tunnel infection is present. This approach is effective because first-generation cephalosporins provide excellent coverage against MSSA while achieving high concentrations in the peritoneal fluid when administered intraperitoneally, allowing direct delivery to the site of infection, as supported by the Infectious Diseases Society of America guidelines 1. Some key points to consider in the management of MSSA peritoneal dialysis catheter-associated peritonitis include:
- Obtaining cultures before starting antibiotics
- Reassessing therapy based on culture results and clinical improvement
- Considering catheter removal if there is no improvement within 5 days, if there are recurrent episodes, or if tunnel infection is present
- Using vancomycin as an alternative for patients with beta-lactam allergies
- Administering antibiotics intraperitoneally to achieve high concentrations in the peritoneal fluid. The most recent and highest quality study, although not directly addressing peritoneal dialysis catheter-associated peritonitis, provides guidance on the management of catheter-related infections, including the use of cefazolin for MSSA infections 1.
From the Research
Antibiotic of Choice for MSSA Peritoneal Dialysis Catheter-Associated Peritonitis
- The antibiotic of choice for Methicillin-sensitive Staphylococcus aureus (MSSA) peritoneal dialysis (PD) catheter-associated peritonitis is cefazolin, as it has been shown to be effective in treating MSSA peritonitis 2, 3, 4.
- Cefazolin is a first-generation cephalosporin that has been used as an initial empiric therapy for PD peritonitis, including MSSA peritonitis 3.
- The use of cefazolin has been compared to vancomycin, and while vancomycin may be more effective in achieving a complete cure, cefazolin is a suitable alternative for MSSA peritonitis 5, 6.
- The dosage and administration of cefazolin vary, but it is often given intraperitoneally (IP) in a once-daily regimen, which has been shown to be effective in treating APD peritonitis 2, 4.
Comparison with Vancomycin
- Vancomycin is often used as an initial empiric therapy for PD peritonitis, including MSSA peritonitis, but its use has been associated with an increased risk of vancomycin-resistant strains 3, 5.
- Cefazolin has been shown to be a suitable alternative to vancomycin for MSSA peritonitis, with similar outcomes and fewer concerns about resistance 2, 3, 4.
- The choice between cefazolin and vancomycin may depend on the specific clinical situation and the susceptibility of the infecting organism 3, 5, 6.
Clinical Outcomes
- The clinical outcomes of MSSA peritonitis treated with cefazolin are generally favorable, with high rates of successful treatment and low rates of relapse and catheter removal 2, 3, 4.
- However, the outcomes may vary depending on the specific clinical situation, the severity of the infection, and the presence of underlying comorbidities 3, 5, 6.