Unchanged Antibiotic Susceptibility in <i>Escherichia coli</i> and <i>Pseudomonas aeruginosa</i> after Long-Term in vitro Exposure to Antineoplastic Drugs

Abstract

Background: Certain antineoplastic drugs inhibit bacterial growth. Whether these drugs also cause genetic changes in bacteria that lead to increased antibiotic resistance is not yet documented. Given the massive and repeated antibiotic treatment most cancer patients undergo, this question is important. We have examined the possible effects of in vitro long-term antineoplastic exposure on antibiotic resistance. Methods: Using the disc diffusion method, two bacterial strains (Escherichia coli, ATCC 25922, and Pseudomonas aeruginosa, ATCC 27583) were exposed to methotrexate, fluorouracil, vincristine, doxorubicin and cytarabine during 50 overnight cycles. The bacterial strains were susceptibility-tested to several antibiotics before and after repeated exposure to antineoplastics. Results: No changes in antibiotic susceptibility were seen in the two bacterial strains after long-term exposure to any of the antineoplastic drugs tested. Conclusion: Long-term in vitro antineoplastic exposure did not change the antibiotic susceptibility in the E. coli or P. aeruginosa strains.

Impact of extensive antibiotic treatment on faecal carriage of antibiotic-resistant enterobacteria in children in a low resistance prevalence setting

“…Further, we cannot exclude that repeated exposures to cytostatic chemotherapy per se also have an impact on the gut flora, including the level of resistance. Studies on this issue are lacking, although some researches have studied the effects of antineoplastic drugs, alone or in combination with antibiotics, on bacterial growth in vitro , with conflicting results [ 61 – 64 ].…”

The Weaned Pig as a Model for Doxorubicin-Induced Mucositis

“…There is a need to better understand how chemotherapy-induced changes in the GI microbiome contribute to mucositis [49,50,51]. Of particular interest is the definition of the mechanisms and pathways leading to the mucosal inflammation associated with mucosal injury such as that seen in CIM.…”

Repurposing High-Throughput Screening Identifies Unconventional Drugs with Antibacterial and Antibiofilm Activities against Pseudomonas aeruginosa under Experimental Conditions Relevant to Cystic Fibrosis

“…Its antibacterial effect requires its incorporation into RNA at transcription, thereby interfering with thymine synthesis ( 59 ), but the inhibition of cell wall synthesis was also reported ( 63 ). Long-term in vitro exposure to 5-fluorouracil did not change the antibiotic susceptibility in P. aeruginosa strains ( 64 ). In addition, it could be a good candidate for in vivo use as an antivirulence drug against P. aeruginosa .…”