Methicillin- and penicillin- susceptible Staphylococcus aureus pneumonia
Aliberti, 2016Australian Commission on Safety and Quality in Health Care (ACSQHC), 2023Charles, 2008McMullan, 2016Metlay, 2019Uranga, 2016
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 adults and children with MSSA pneumonia, use:
1cefazolin 2 g (child: 50 mg/kg up to 2 g) intravenously, 8-hourly. For patients with high-severity pneumonia, septic shock or requiring intensive care support, use a 6-hourly dosing interval. For dosage adjustment in adults with kidney impairment, see cefazolin dosage adjustment. See advice on intravenous to oral switch and duration of therapy cefazolin cefazolin cefazolin
OR
1flucloxacillin 2 g (child: 50 mg/kg up to 2 g) intravenously, 6-hourly. For patients with high-severity pneumonia, endocarditis, septic shock or requiring intensive care support, use a 4-hourly dosing interval. For dosage adjustment in adults with kidney impairment, see flucloxacillin intravenous dosage adjustment. See advice on intravenous to oral switch and duration of therapy. flucloxacillin flucloxacillin flucloxacillin
Accumulating evidence suggests that cefazolin is as effective as flucloxacillin for the treatment of methicillin-susceptible S. aureus pneumonia and may have lower risk of acute kidney injury. However, there are no published randomised controlled trials comparing cefazolin with flucloxacillin for this indication.
Some MSSA isolates are susceptible to penicillin (eg benzylpenicillin); however, confirmation of penicillin-susceptible S. aureus (PSSA) can be challenging. For confirmed PSSA pneumonia in adults and children, use:
benzylpenicillin 2.4 g (child: 60 mg/kg up to 2.4 g) intravenously, 6-hourly. For dosage adjustment in adults with kidney impairment, see benzylpenicillin dosage adjustment. See advice on intravenous to oral switch and duration of therapy. benzylpenicillin benzylpenicillin benzylpenicillin
For patients with MSSA or PSSA pneumonia who have had a nonsevere (immediate or delayed) or a severe immediate1 hypersensitivity reaction to a penicillin, use cefazolin (see dosage above).
For patients with MSSA or PSSA pneumonia who have had a severe delayed2 hypersensitivity reaction to a penicillin, use:
vancomycin 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.
If the isolate is susceptible and bacteraemia has been excluded, consider changing vancomycin to:
clindamycin 600 mg (child: 15 mg/kg up to 600 mg) intravenously, 8-hourly3. See advice on intravenous to oral switch and duration of therapy. clindamycin clindamycin clindamycin