Prevalence of Pseudomonas aeruginosa’s Virulence Genes Isolated from Human Infection in Abidjan, Côte d’Ivoire

The aim of this study was to evaluate the distribution of virulence genes among clinical isolates of P. aeruginosa and to compare these factors with the localisation of clinical infection and the serotypes.

151 isolates of P. aeruginosa were collected from various biological fluids: The strains were identified based on the standard bacteriological characteristics. The serotyping of the strains was done. The Detection of virulence genes was done by polymerase chain reaction (PCR). The genes sought were: PilB, lasB, nan1, algD, plcH, exoS, and exoU genes.

The most common virulence factor found in clinical strains of P. aeruginosa was, alg D (encoding for alginate) with a prevalence of 90.7%, plch (haemolytic phospholipase C precusor) with 84.1%, las B (elastase B) 72.8%, pilB (type IV fimbrial biogenesis protein pilB) 70.2%, nan1 (neuraminidase) 37.1%, exoS (exotoxin S) 31.1% and exoU (exotoxin U) 17.9 %. Infections with the highest virulence levels were sepsis and lung infections. The exoS gene was more frequently found in serotypes O2 (43%), O4 (39%) and O3 (25%). As for the exoU gene, the prevalent serotypes were O11 (28.8%) and O1 (20%). The multidrug resistant P. aeruginosa isolates were most frequently associated with the presence of algD (78.6%), plch (71.4%), lasB (64.3%), pilB (42%), and nan 1 (42%).

P. aeruginosa of invasive infections like septis and lung infections had the highest level of virulence.