Fusidic acid in a tertiary hospital: an observational study focusing on prescriptions, tolerance and susceptibility of Staphylococcus and Cutibacterium spp. strains from bone samples.

ABSTRACT

Adverse drug reactions of broad-spectrum fluoroquinolones or rifampicin are not uncommon during osteomyelitis and orthopaedic implant infections (OOII). Thus, we made an overview (i) of the prescription of fusidic acid (FA) and (ii) of FA susceptibility of Staphylococcus sp. and Cutibacterium sp. strains isolated from bone samples. All prescriptions of FA and all bone samples with positive culture for Staphylococcus sp. or Cutibacterium sp. (Reims University Hospital June 2017-May 2021) were included. All Staphylococcus aureus strains were considered as significant, whereas Coagulase-negative Staphylococcus and Cutibacterium spp. strains were not if these strains grew only on one sole sample. The antibiotic susceptibility of Staphylococcus sp. strains and the susceptibility to FA of Cutibacterium sp. strains had been determined using disk diffusion methods, as described for Staphylococcus sp. in the CASFM/EUCAST guidelines. The mean FA consumption was 0.6 daily defined doses/1000 patient days. FA was prescribed for OOII due to Staphylococcus sp. and Cutibacterium sp. in 24 and 2 cases, respectively. Among 401 Staphylococcus sp. strains, there were 254 S. aureus (63.3%), 84 methicillin-resistant (20.9%) and 333 FA-susceptible (83.0%) strains. S. aureus and methicillin-sensitive strains were more likely to be susceptible to FA (p < 0.001). Among 39 Cutibacterium sp. strains, the FA inhibition zone diameter geometric mean was 28.6 mm (24-35 mm), suggesting that all these strains could be considered as susceptible to FA. These data suggested that FA could be more frequently used in OOII due to Staphylococcus sp. and Cutibacterium sp., subject to the absence of other resistant bacteria.