From the FDA Drug Label
DOSAGE AND ADMINISTRATION Nafcillin for Injection, USP is available for intramuscular and intravenous use. In severe staphylococcal infections, therapy with nafcillin should be continued for at least 14 days
The drug of choice for Methicillin-Sensitive Staphylococcus aureus (MSSA) meningitis in children is nafcillin. The recommended duration of treatment is at least 14 days for severe staphylococcal infections, but the exact duration may vary depending on the clinical and bacteriological response of the patient 1.
- The dosage for children is 25 mg/kg IM twice daily for those less than 40 kg (88 lbs).
- For severe infections, the dosage is 1 gram IM or IV every 4 hours for adults, but the pediatric equivalent is not explicitly stated.
From the Research
For MSSA (Methicillin-Sensitive Staphylococcus aureus) meningitis in children, the drug of choice is cefazolin administered intravenously, due to its comparable efficacy and better tolerability compared to nafcillin or oxacillin, as supported by recent studies 2, 3, 4. The recommended dosage of cefazolin is 100-150 mg/kg/day divided into doses given every 8 hours, with a maximum daily dose of 6 grams. The standard duration of treatment is 2 weeks for uncomplicated cases, but this should be extended to 4-6 weeks if there are complications such as brain abscesses, subdural empyema, or if the patient has endocarditis. Some key points to consider in the treatment of MSSA meningitis include:
- Vancomycin (60 mg/kg/day divided every 6 hours) may be used initially if MRSA cannot be ruled out, but should be discontinued once methicillin sensitivity is confirmed.
- For patients with severe penicillin allergies, cefazolin can be considered if the allergy is not anaphylactic, due to its relatively low cross-reactivity with penicillins.
- Therapeutic drug monitoring is essential, particularly when using vancomycin, to ensure adequate CNS penetration while avoiding toxicity.
- Supportive care including management of increased intracranial pressure, seizure prophylaxis, and close neurological monitoring are also critical components of treatment. The choice of cefazolin over nafcillin or oxacillin is supported by studies showing its comparable efficacy and better tolerability in the treatment of MSSA infections 2, 3, 4. Additionally, cefazolin has been shown to be effective in the treatment of MSSA spinal epidural abscesses, a condition similar to meningitis in terms of the need for effective CNS penetration of antibiotics 4. Overall, the use of cefazolin as the drug of choice for MSSA meningitis in children is supported by recent evidence and should be considered in clinical practice, prioritizing morbidity, mortality, and quality of life as the primary outcomes 2, 3, 4.