Written by Megan Hilbert
Current guidelines dictate that treatment of Group A Streptococcus pyogenes (GAS) necrotizing soft tissue infections (NSTI) and toxic shock syndrome (TSS) include clindamycin in conjunction to a beta lactam in order to inhibit exotoxin production; but might we consider co-treatment with linezolid instead?
Why does this matter?
Virulence of GAS is due to pyogenic exotoxin production and can cause upwards of 30% mortality and 1,100 deaths annually. Clindamycin resistant strains have doubled since 2016 (now up to 29.1%) and are associated with greater risk of amputation (86% with risk ratio of 1.86 (95%CI 1.1-3.16).
Cling to clindamycin or let linezolid in to our treatment algorithm?
This paper is a focused debate published in Clinical Infectious Diseases. The first author encourages continued use of clindamycin given better in vitro/in vivo research as well as a wealth of clinical evidence. Meta-analysis has demonstrated that clindamycin results in reduced overall mortality (odds ratio [OR] 0.45; 95%CI 0.27-0.28). Clindamycin-resistant GAS strains have also been preliminarily found to have overall decreased virulence. Given this and universal susceptibility to penicillin, they posit that there may be no future need for clindamycin even as clindamycin-resistant strains increase.
The second author encourages the consideration of linezolid given that GAS remains 100% susceptible. While there is a generalized lack of research (and particularly clinical data), one study found that the penicillin-linezolid combination resulted in similar reduction of exotoxin release as compared to penicillin-clindamycin. Linezolid also carries the advantage that it has a lower risk of Clostridiodes difficile infection and has good MRSA coverage.
I find this debate intriguing and very apropros in the era of antibiotic stewardship. Given that there is no significant clinical research demonstrating improved outcomes with linezolid over clindamycin, I don’t anticipate a change in the guidelines any time soon. I do, however, look forward to the possibility in the future.
Should Linezolid Replace Clindamycin as the Adjunctive Antimicrobial of Choice in Group A Streptococcal Necrotizing Soft Tissue Infection and Toxic Shock Syndrome? A Focused Debate. Clin Infect Dis. 2023 Jan 13;76(2):346-350. doi: 10.1093/cid/ciac720.