Inducible clindamycin resistance among clinical Gram-positive cocci in a tertiary hospital in Niger Republic

Background. Macrolide-induced resistance to clindamycin is a well-described mechanism leading to treatment failure. Herein, we determined the frequency and associated factors of inducible clindamycin resistance in Gram-positive cocci in a tertiary care hospital. Methods. A cross-sectional descriptive study was carried out between January and December 2022. D tests were performed as recommended by EUCAST 2021 guidelines on 100 non-duplicate clinical isolates of Gram-positive cocci to determine the prevalence of methicillin resistance and inducible clindamycin resistance among the collected isolates. Results. Of the 100 Gram-positive cocci isolates, 56 (56.0 %), 17 (17.0 %) and 27 (27.0 %) were respectively coagulase-negative staphylococci, Staphylococcus aureus and Streptococcus spp. Among Streptococcus spp., Group D Streptococci (15.0%) were the most isolated. Methicillin-resistant Staphylococcusaureus (MRSA) represented 9 (53.0 %) of S.aureus isolates. Constitutive (cMLSb) and inducible clindamycin resistance (iMLSb) phenotypes were detected in 36 (36.0%) and 14 (14,0%) of the isolates, respectively. S. aureus exhibited 38.4% of cMLSb and 13.7% of iMLSb. The result of multivariate analysis showed that age groups, gender, type of samples, provenance, and bacteria, were not significantly associated with Gram-positive cocci iMLSb phenotype. Conclusion. The study reported for the first time a high prevalence of inducible resistance of Gram-positive cocci strains to clindamycin in Niger Republic. This suggests the urgent need for the implementation of regular screening of these isolates and the wise use of clindamycin in clinical practice.