Emerging erythromycin and clindamycin resistance in group A streptococcus: Efficacy of linezolid and tedizolid in experimental necrotizing infection.
J Glob Antimicrob Resist. 2020 May 11;:
Authors: Bryant AE, Bayer CR, Aldape MJ, McIndoo E, Stevens DL
BACKGROUND: Clindamycin (Clin) and erythromycin (Ery) resistance is increasing among group A streptococcus (GAS) causing invasive disease and newer treatments are urgently needed. We compared the efficacy of the newer oxazolidinone, tedizolid (Tzd), with the first drug in this class, linezolid (Lzd) in experimental murine myonecrosis caused by Ery/Clin-sensitive or -resistant GAS.
METHODS: Normal adult outbred Swiss Webster female mice (10/group) were infected intramuscularly with EryS/ClinS (ATCC 12384) or EryR/ClinR GAS (VA 15-003). Treatments began 4 h post-infection and continued for 72 h. Tzd and Lzd (40, 20, 10 mg/kg) were given q12 h. Saline, penicillin (Pen), Clin and Ery were given q6h. Survival and infection severity signs and symptoms were followed for 12 d.
RESULTS: Both GAS strains were sensitive to Lzd, Tzd and Pen; GAS 15-003 was confirmed as constituently resistant to Ery and Clin. Blood levels of Lzd40 and Tzd40 were 30.9 ± 4.0 and 21.9 ± 5.3 ug/mL, respectively. Both Tzd and Lzd were highly efficacious for treatment of severe experimental myonecrosis caused by Ery/Clin-sensitive and importantly, Ery/Clin-resistant, GAS.
CONCLUSIONS: In the current era of emerging macrolide/lincosamide resistance among group A streptococcus, these data support the use of Tzd and Lzd as first line antibiotics for the treatment of life-threatening GAS infections in humans.
PMID: 32408046 [PubMed - as supplied by publisher]