High incidence of type III secretion system associated virulence factors (exoenzymes) in Pseudomonas aeruginosa isolated from Iranian burn patients

BMC Res Notes. 2019 Jan 15;12(1):28. doi: 10.1186/s13104-019-4071-0.

Abstract

Objective: The present study aimed to determine the prevalence of virulence factors and antimicrobial resistance profile of Pseudomonas aeruginosa strains isolated from Iranian burn patients.

Results: This cross-sectional study performed on 100 P. aeruginosa isolates which were recovered from burn wound specimens in 2014-2015. All presumptive isolates were identified by standard microbiologic tests. Antimicrobial susceptibility test was carried out by disk diffusion method. The presence of virulence genes was determined by PCR method. Antibiotic susceptibility results revealed that the isolates were mostly susceptible to amikacin (61%), ceftazidime (60%), and imipenem (55%). Moreover, 59% of the isolates were multi-drug resistance (MDR). The most prevalent MDR pattern was aminoglycosides-penicillins-fluoroquinolones-carbapenems (15%). The presence of exoT, exoY, exoS and exoU genes was detected in 100%, 100%, 59%, and 41% of the tested isolates, respectively. Results points out the pattern of MDR and genetic diversity of type III secretion system among P. aeruginosa strains isolated from the burn population. Overall, the association of MDR and the presence of the specific virulence genes can be a predictive marker for the persistence of these isolates in the hospitals and subsequently a worse clinical condition for the affected patients.

Keywords: Antimicrobial resistance; Burn patients; Pseudomonas aeruginosa; Type III secretion system; Virulence factors.

MeSH terms

  • ADP Ribose Transferases / genetics*
  • Anti-Bacterial Agents*
  • Bacterial Proteins / genetics*
  • Bacterial Toxins / genetics*
  • Burn Units*
  • Burns / microbiology*
  • Cross-Sectional Studies
  • Drug Resistance, Multiple, Bacterial / genetics*
  • GTPase-Activating Proteins / genetics*
  • Glucosyltransferases / genetics*
  • Humans
  • Iran
  • Microbial Sensitivity Tests
  • Pseudomonas aeruginosa / genetics*
  • Pseudomonas aeruginosa / isolation & purification
  • Type III Secretion Systems*
  • Virulence Factors / genetics*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Bacterial Toxins
  • ExoT protein, Pseudomonas aeruginosa
  • GTPase-Activating Proteins
  • Type III Secretion Systems
  • Virulence Factors
  • pseudomonas exoprotein A protein, Pseudomonas aeruginosa
  • ExoY protein, bacteria
  • Glucosyltransferases
  • ADP Ribose Transferases
  • exoenzyme S