Can cefazolin be used to treat Methicillin-Sensitive Staphylococcus aureus (MSSA) bacteremia in pediatric patients?

From the Guidelines

Yes, cefazolin is an appropriate treatment option for methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia in pediatric patients, as indicated by the guidelines for the management of community-acquired pneumonia and skin and soft tissue infections 1. The recommended dosage for children is typically 50 mg/kg/day in 3 divided doses, administered intravenously, as suggested in the guidelines for skin and soft tissue infections 1. Key considerations for treatment include:

• Obtaining blood cultures to confirm the diagnosis and susceptibility before starting cefazolin
• Monitoring clinical response and assessing for potential complications
• Considering alternative agents for central nervous system infections due to cefazolin's poor penetration across the blood-brain barrier
• Treatment duration for uncomplicated MSSA bacteremia is generally 14 days, though this may be extended to 4-6 weeks if there are complications such as endocarditis, osteomyelitis, or other deep-seated infections. Some important points to note:
• Cefazolin is preferred over other options like nafcillin or oxacillin because it has similar efficacy with less frequent dosing, fewer adverse effects, and lower cost 1.
• Cefazolin achieves good serum levels and tissue penetration for treating bloodstream infections, making it a suitable choice for MSSA bacteremia 1.
• The guidelines emphasize the importance of considering the presence or absence of systemic inflammatory response syndrome (SIRS) when deciding on antibiotic treatment, including the use of cefazolin 1.

From the FDA Drug Label

In pediatric patients, a total daily dosage of 25 to 50 mg/kg (approximately 10 to 20 mg/lb) of body weight, divided into 3 or 4 equal doses, is effective for most mild to moderately severe infections. Total daily dosage may be increased to 100 mg/kg (45 mg/lb) of body weight for severe infections Since safety for use in premature infants and in neonates has not been established, the use of cefazolin in these patients is not recommended.

Cefazolin can be used to treat MSSA bacteremia in pediatric patients, with a recommended dosage of 25 to 50 mg/kg per day, divided into 3 or 4 equal doses, for mild to moderately severe infections, and up to 100 mg/kg per day for severe infections 2. However, safety and effectiveness have not been established in premature infants and neonates.

From the Research

Treatment of MSSA Bacteremia in Pediatrics with Cefazolin

• The use of cefazolin for the treatment of methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia has been evaluated in several studies 3, 4, 5, 6, 7.
• A systematic review and meta-analysis found that cefazolin was associated with significant reduction in mortality and clinical failure compared to antistaphylococcal penicillins (ASPs) for the treatment of MSSA bacteremia 3.
• Another study found that cefazolin offers several pharmacologic advantages over ASPs, including more convenient dosing regimens, and is increasingly being used as the preferential agent for MSSA infections as part of cost-saving initiatives 4.
• A retrospective cohort study found that oxacillin MIC (i.e., ≥ 1 versus < 1 μg/mL) was not associated with acute treatment outcomes, regardless of the beta-lactam selected as definitive therapy 5.
• A review of the management of Staphylococcus aureus bacteremia recommends the use of cefazolin or antistaphylococcal penicillins for the treatment of MSSA bacteremia, and emphasizes the importance of source control and identifying sites of metastatic infection 6.
• A study comparing ceftriaxone versus cefazolin for the treatment of MSSA bacteraemia found no difference in clinical cure at 28 days or at discharge between the two groups 7.

Pediatric Considerations

• While the studies mentioned above did not specifically focus on pediatric patients, the principles of treatment for MSSA bacteremia are likely to be similar in children and adults.
• However, it is essential to consider the specific needs and vulnerabilities of pediatric patients when selecting an antibiotic regimen.
• Further research is needed to determine the safety and efficacy of cefazolin in pediatric patients with MSSA bacteremia.

Key Findings

• Cefazolin is a viable option for the treatment of MSSA bacteremia, with several studies demonstrating its efficacy and safety compared to ASPs 3, 4, 5, 6, 7.
• The choice of antibiotic regimen should be individualized based on patient-specific factors, including the severity of illness, comorbidities, and potential allergies or intolerances.
• Source control and identifying sites of metastatic infection are critical components of treating MSSA bacteremia, regardless of the antibiotic regimen used 6.