Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Effect of Sub-inhibitory Dose of Cefotaxime on Multidrug resistant Staphylococcus haemolyticus Isolates

Version 1 : Received: 31 August 2021 / Approved: 1 September 2021 / Online: 1 September 2021 (14:39:54 CEST)

How to cite: Chakraborty, M.; Bardhan, T.; Basu, M.; Bhattacharjee, B. Effect of Sub-inhibitory Dose of Cefotaxime on Multidrug resistant Staphylococcus haemolyticus Isolates. Preprints 2021, 2021090026 (doi: 10.20944/preprints202109.0026.v1). Chakraborty, M.; Bardhan, T.; Basu, M.; Bhattacharjee, B. Effect of Sub-inhibitory Dose of Cefotaxime on Multidrug resistant Staphylococcus haemolyticus Isolates. Preprints 2021, 2021090026 (doi: 10.20944/preprints202109.0026.v1).

Abstract

Critical care of neonates involves substantial usage of antibiotics and exposure to multidrug resistant (MDR) nosocomial pathogens. These pathogens are often exposed to sub-MIC doses of antibiotics which might result in a range of physiological effects. Therefore, to understand the outcome of sub-inhibitory dosage of antibiotics on Staphylococcus populations, nasal swab specimens were collected from 34 neonates admitted to the Sick Newborn Care Unit between 2017-2018, a total of 41 non-repetitive isolates were included in this study. Staphylococcus haemolyticus was the prevalent species (58.54%) with high non-susceptibility to cefotaxime (CTX) (79.16%), gentamicin (87.50%), and meropenem (54.17%). Biofilm forming abilities of S. haemolyticus isolates in the presence of sub-optimal CTX (30μg/mL), the predominantly prescribed β-lactam antibiotic, were then determined by crystal violet assays and extracellular DNA (eDNA) quantitation. CTX was found to significantly enhance biofilm production among the non-susceptible isolates (p-valueWilcoxin test- 0.000008) with increase in eDNA levels (p-valueWilcoxin test- 0.000004). Additionally, no changes in non-susceptibility were observed among populations of two MDR isolates, JNM56C1 and JNM60C2 after >500 generations of growth in the absence of antibiotic selection in vitro. These findings demonstrate that sub-MIC concentration of CTX induces biofilm formation and short-term non-exposure to antibiotics does not alter non-susceptibility among S. haemolyticus isolates.

Keywords

Cefotaxime; S. haemolyticus; neonates; sub-MIC; biofilms; short-term evolution

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.