REPLY
My coauthors and I are very grateful to Dr. Edelstein for his interest in our article and suggestions, and we agree with his comments (1). In our study, 149 strains of Legionella pneumophila isolated from clinical cases or environmental water in China were used to detect their resistance to five antibiotics (2). Among them, 25 strains showed azithromycin resistance, and the mechanisms leading to this antibiotic resistance were related to the overexpression of the lpeAB-encoded efflux pump. Among the 25 strains, 60% were more virulent than the ATCC 33152 reference strain. The 25 strains showed a low level of azithromycin resistance that was about two times higher than the EUCAST epidemiological threshold (1 μg/ml). It may not be possible clinically to show treatment failure, but we believe that it is worth highlighting that the susceptibility to this antibiotic is reduced.
Footnotes
This is a response to a letter by Edelstein (https://doi.org/10.1128/AAC.01986-19).
REFERENCES
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