Chloraminated drinking water does not generate bacterial resistance to antibiotics in Pseudomonas aeruginosa biofilms

Abstract

Aim: To determine if exposure of Pseudomonas aeruginosa biofilms to chloraminated drinking water can lead to individual bacteria with resistance to antibiotics. Methods and Results: Biofilms of P. aeruginosa PA14 were grown in drinking water in a Kadouri drip‐fed reactor; the biofilms were treated with either 0·5 mg l‐1 or 1·0 mg l‐1 of chloramine for 15 or 21 days; control biofilms were grown in water without chloramine. Fewer isolates with antibiotic resistance were obtained from the chloramine‐treated biofilms as compared to the control. Minimum inhibitory concentrations (MIC) for selected antibiotic‐resistant isolates were determined using ciprofloxacin, tobramycin, gentamicin, rifampicin and chloramphenicol. All of the isolates tested had increased resistance over the wildtype to ciprofloxacin, rifampicin and chloramphenicol, but were not resistant to tobramycin or gentamicin. Conclusions: Under these test conditions, there was no detectable increase in antibiotic resistance in P. aeruginosa exposed as biofilms to disinfectant residues in chloraminated drinking water. Significance and Impact of the study: Chloramine in drinking water, while unable to kill biofilm bacteria, does not increase the potential of P. aeruginosa to become resistant to antibiotics.

In vitrosusceptibility ofStaphylococcus aureusstrains isolated from cows with subclinical mastitis to different antimicrobial agents

“…Differences in MIC values did not affect classifications of all strains, which were all susceptible to antimicrobial agents according to EUCAST breakpoint guidelines. Similar findings were reported by Jurgens et al [16], Birošová and Mikulášová [2], and Cottell et al [6]. However, our result was not in agreement with those obtained by Karatzas et al [17] or Randall et al [27].…”

Selection and Transmission of Antibiotic-Resistant Bacteria

“…In a recent study investigating the use of chloraminated drinking water against Ps. aeruginosa biofilm, there was no evidence that the use of chloramine induced an increase in antibiotic resistance (Jurgens et al 2008).…”

“…In one study (Jurgens et al 2008), the aim of which was to determine if exposure of Pseudomonas aeruginosa biofilms to chloraminated drinking water could lead to individual bacteria with resistance to antibiotics, it has been demonstrated that exposure to chloramine does not increase antibiotic resistance in this bacterial species.…”

Options and Limitations in Clinical Investigation of Bacterial Biofilms

“…3E). The major difference from static assays is that the wells are part of a closed system with two outputs, one for the continuous fresh medium supply via an adjusted pump and one for the removal of waste and planktonic cells, while the difference from flow-cell systems lies in the minimal shear forces (93,116).…”