Methicillin-resistant Staphylococcus aureus pneumonia
Aliberti, 2016Australian Commission on Safety and Quality in Health Care (ACSQHC), 2023Charles, 2008Kalil, 2016McMullan, 2016Metlay, 2019
When treating patients with Staphylococcus aureus bacteraemia and staphylococcal pneumonia, consider both the recommendations in this topic and the recommendations in Staphylococcus aureus bacteraemia, including sepsis and septic shock.
For methicillin-resistant S. aureus (MRSA) pneumonia, vancomycin is usually first line; however, linezolid should be used if:
- staphylococcal pneumonia is caused by S. aureus strains with reduced susceptibility to vancomycin (vancomycin-intermediate S. aureus [VISA] or heteroresistant VISA [hVISA])
- staphylococcal pneumonia is not responding to vancomycin
- use of vancomycin is precluded due to vancomycin toxicity
- therapeutic drug monitoring of vancomycin is not feasible.
For adults and children with MRSA pneumonia, use:
1vancomycin intravenously; see advice on intravenous to oral switch and duration of therapy vancomycin vancomycin vancomycin
adult: 25 mg/kg (actual body weight) rounded up to nearest 125 mg, up to 3 g, as a loading dose. See Calculated vancomycin loading dosage in critically ill adults for calculated weight-based loading doses. Subsequent doses are dependent on weight and kidney function; see Intermittent vancomycin dosing for critically ill adults
child: for initial dosing, see Intermittent vancomycin dosing for young infants and children
OR
2linezolid intravenously; see advice on intravenous to oral switch and duration of therapy linezolid linezolid linezolid
adult, or child older than 12 years: 600 mg, 12-hourly. For dosage adjustment in adults with kidney impairment, see linezolid dosage adjustment
child 12 years or younger: 10 mg/kg up to 600 mg intravenously, 8-hourly.
The optimal dosage of linezolid in critically ill patients is not well established.
For life-threatening or necrotising pneumonia, consider adding clindamycin to vancomycin (see dosage below), and seek expert advice; use:
clindamycin 600 mg (child: 15 mg/kg up to 600 mg) intravenously, 8-hourly1. See advice on intravenous to oral switch and duration of therapy. clindamycin clindamycin clindamycin
If the isolate is susceptible and bacteraemia has been excluded, consider changing vancomycin or linezolid to clindamycin (see dosage above).
Although daptomycin and tigecycline have activity against MRSA, these drugs are not recommended because of poor or uncertain efficacy for the treatment of pneumonia.