β-lactamase producing Pseudomonas aeruginosa recovered from disinfectants frequently used in Tertiary Care Hospitals in Khartoum

Abstract

Background: Disinfectants are an important tool for infection control in hospitals. However, some bacteria are resistant to these disinfectants and/or can indeed be found in them as contaminants. The purpose of this study is to examine the presence of Pseudomonas aeruginosa (P. aeruginosa) as a possible contaminant in disinfectants used in a sample of hospitals in Khartoum, Sudan.

Methods: This cross-sectional study was carried out between November 2020 and October 2021. A total of 45 disinfectant samples from nine hospitals in Khartoum were analyzed. Phenotypic methods including gram staining, culture and biochemical tests along with genotypic methods based on Polymerase Chain Reaction (PCR) were utilized to detect the presence of P. aeruginosa. The disc diffusion method was used to test the antibiotic susceptibility of bacterial isolates. Several ß-lactamase genes were also identified using PCR.

Results: Seven samples (15.5%) of the 45 disinfectant samples were found to be contaminated with P. aeruginosa. These samples were from different types of disinfectants. Samples of chloroxylenol type were found to be predominantly contaminated. P. aeruginosa was also detected in sodium hypochlorite and chlorhexidine gluconate-cetrimide types of disinfectants. Several P. aeruginosa isolates exhibited resistance to agents of both the penicillins and cephalosporins groups of antibiotics and many strains were found to be positive for blaTEM-1 resistance gene.

Conclusions: The investigation showed a considerable amount of contamination with P.aeruginosa. Microbial contamination of disinfectants with P. aeruginosa is considered a matter of concern and poses a great risk to patients in hospitals. It is essential to use different strategies to monitor the spread of this pathogen.