title: Integron occurrence is linked to reduced biocide susceptibility in multidrug resistant Pseudomonas aeruginosa.
abstract: OBJECTIVE
  Integrons are gene acquisition systems commonly found in bacterial genomes that play a major role in the dissemination of resistance to antibiotics. This work aimed to study the relationship between the presence of integrons and the reduced susceptibility of multidrug-resistant (MDR) Pseudomonas aeruginosa isolates towards different groups of biocides.
  
  
  METHODS
  The antimicrobial susceptibility patterns of 104 clinical isolates were determined against different antibiotics by the disk diffusion method. The isolates were also tested for their susceptibility to six biocides (glutaraldehyde, benzalkonium chloride, cetrimide, chlorhexidine gluconate, chlorocresol and gluconate, and phenyl mercuric nitrate) by agar dilution. The presence of integrons and resistance genes in MDR isolates were detected by polymerase chain reaction.
  
  
  RESULTS
  Thirty-six Pseudomonas isolates were MDR, and the majority of these isolates showed reduced susceptibility to biocides. In the MDR isolates, Class I integron was detected in 22 isolates (61.1%), while Class II and III integrons were identified in only four isolates (11.1%), In addition, aacA4 and qacE genes were detected in 22 (61.1%) and 11 (30.5%) isolates, respectively. Integron I-positive isolates showed reduced susceptibility to tested biocides.
  
  
  CONCLUSIONS
  The current study reveals the presence of different classes of integrons, with class I being predominant. Class I integron may be responsible for generating MDR P. aeruginosa isolates with reduced susceptibility to biocides. This linkage between integrons and biocide resistance in MDR-Pseudomonas isolates is notable and could be clinically important. Strict antibiotic prescription policies and the adequate use of biocides could help in controlling this problem.
authors.affiliation: a Faculty of Pharmacy, Microbiology and Immunology Department , Zagazig University , Zagazig , Egypt.
authors.forename: Ashraf A
authors.initials: AA
authors.lastname: Kadry
authors.affiliation: a Faculty of Pharmacy, Microbiology and Immunology Department , Zagazig University , Zagazig , Egypt.
authors.forename: Fathy M
authors.initials: FM
authors.lastname: Serry
authors.affiliation: a Faculty of Pharmacy, Microbiology and Immunology Department , Zagazig University , Zagazig , Egypt.
authors.forename: Amira M
authors.initials: AM
authors.lastname: El-Ganiny
authors.affiliation: b Faculty of Pharmacy, Microbiology and biotechnology Department , Delta University , Gamasa , Egypt.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: El-Baz
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004202:Disinfectants / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000235:genetics; D005798:Genes, Bacterial; D032023:Integrons / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D004202:Disinfectants
keywords: Integrons; Pseudomonas aeruginosa; antibiotics; biocides; multidrug resistance