Relationship between algD gene and biofilm density in clinical isolates of Pseudomonas Aeruginosa

Introduction: infection due to Pseudomonas aeruginosa is a cause of nosocomial infections that are acquired when patients are hospitalized. The incidence of bacterial infections is 80 % related to biofilm formation, which is the main mediator of infection. Pseudomonas aeruginosa genetically produces at least three polysaccharides that help the biofilm formation process and maintain the stability of the biofilm structure, one of which is the algD gene. Objective: analyze the relationship between the presence of the algD gene and biofilm density in clinical isolates of Pseudomonas aeruginosa. Method: analytical observational research, consecutive sampling technique with a total sample of 33 clinical isolates of Pseudomonas aeruginosa. The biofilm formation test uses the microtiter plate assay method to determine the presence of the algD gene in the conventional PCR method. Results: the results of the biofilm development process showed that 4 isolates (12,1 %) did not produce biofilm and 29 isolates (87,9 %) produced biofilm, including 10 isolates (30,3 %) produced weak biofilm, 13 isolates (39,4 %) produces moderate biofilm. And 6 isolates (18,2 %) produced strong biofilms. Based on PCR amplification, 31 isolates (93,9) carried the algD gene and 2 isolates (6,1 %) did not carry the algD gene. The statistical analysis results using the chi-square test obtained a p-value = 0,011. Conclusion: There is a significant relationship between the presence of the algD gene and biofilm density in clinical isolates of Pseudomonas aeruginosa.