Daptomycin and linezolid for severe methicillin-resistant Staphylococcus aureus psoas abscess and bacteremia: A case report and review of the literature

Table 1 Antimicrobial-susceptibility of the isolated strain on May 30^th and June 7^th

Antibiotics	MIC (mg/mL)		MIC categories
	Pre-test	Post-test	Pre-test	Post-test
Penicillin G	≥ 0.5	≥ 0.5	R	R
Oxacillin	≥ 4	≥ 4	R	R
Gentamicin	≤ 0.5	≤ 0.5	S	S
Levofloxacin	0.5	0.5	S	S
Erythromycin	≥ 8	≥ 8	R	R
Clindamycin	≥ 4	≥ 4	R	R
Linezolid	2	2	S	S
Teicoplanin	≤ 0.5	≤ 0.5	S	S
Vancomycin	≤ 0.5	1	S	S
Tigecycline	≤ 0.12	≤ 0.12	S	S

Main treatment course and monitoring. MIC: Minimal inhibitory concentration; R: Resistance; S: Susceptible.

Table 2 Clinical factors, treatment details, and outcomes among 3 patients treated with Daptomycin and linezolid for methicillin-resistant Staphylococcus aureus bacteremia and complication.

Patients	Ref.	Reason for Daptomycin/linezolid use	Host factors	Complication	Prior antimicrobialtherapy	Other active antimicrobials available	Daptomycin/linezolid dose; duration	MIC (mg/mL)	Outcome, follow-up duration
1	Kelesidis et al[21], 2011	Allergy	62 y/o with placement of the coatrial andlumboperitoneal shunts	Meningitis	Daptomycin	Vancomycin	Daptomycin (NS); linezolid (600 mg twice daily); 4 d	Daptomycin (≤ 0.5 μg /mL), vancomycin (1 μg /mL), linezolid (4 μg/mL), rifampin (0.06 μg/mL)	Clinical cure, NS
2	Yazaki et al[22], 2018	Allergy, acute kidney injury	26 y/o woman with surgical closure of ventricular septal defect	Septic pulmonary embolism	Levofloxacin, meropenem, azithromycin, vancomycin, rifampicin, gentamicin	None	Daptomycin (8 mg/kg q48h), linezolid (600 mg q12h); 6 wk	Vancomycin (1 μg/mL), Linezolid (2 μg/mL), Daptomycin (1 μg/mL)	Clinical cure, 2 mo
3	Galanter et al[23], 2019	Vancomycin resistance, worsening of septic emboli in both lungs, blood cultures remained positive for MRSA	26 y/o woman with native tricuspid value endocarditis	Suspected septic embolism	Vancomycin, daptomycin, gentamicin	None	Daptomycin (8 mg/kg iv daily), linezolid (600 mg iv twice daily), 15 d	Daptomycin 1 μg/mL; daptomycin MIC 4 μg/mL (on the 15th day)	Clinical cure, 6 wk

y/o: Year old; NS: Not specified; MRSA: Methicillin-resistant Staphylococcus aureus; MIC: Minimum inhibitory concentration.