Acta Scientific Microbiology (ISSN: 2581-3226)

Research Article Volume 4 Issue 12

Study of Resistance Mechanisms and Evaluation of Biofilm Detection Tests in Clinical Isolates of Pseudomonas aeruginosa Circulating in Yaounde, Cameroon

Yves Le Grand Napa Tchuedji1,2*, Hortense Gonsu Kamga3,4, Emilia Lyonga Mbamyah2,3, Anicette Chafa Betbeui3,4, Ibrahim Assana Raoul5, Giselle Fonyuy Bongnyang6, Etienne Guenou2 and Francois-Xavier Etoa1

1Department of Microbiology, Laboratory of Microbiology, University of Yaoundé I, Cameroon

2Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Cameroon

3Department of Microbiology, Haematology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Cameroon

4Laboratory of Bacteriology, University Teaching Hospital, Cameroon

5University and strategic institute of the estuary, Cameroon

6General Hospital of Yaoundé, Cameroon

*Corresponding Author: Yves Le Grand Napa Tchuedji, Department of Microbiology, Laboratory of Microbiology, University of Yaoundé I, Cameroon.

Received: October 20, 2021; Published: November 29, 2021


Background: Antibiotic resistance is a priority problem around the world. The occurrence of SARS-CoV-2 in a context where the resistance of Pseudomonas aeruginosa is increasing, could promote the cohabitation of these microorganisms and an increase in the risk of clinical damage and mortality in infected patients.

Aim: The aim of this study is to determine resistance strategies of clinical isolates of Pseudomonas aeruginosa that circulate in Yaoundé, Cameroon.

Method: A descriptive cross-sectional study was carried out from May 2019 to November 2020. A randomized sampling was conducted. The study of resistance phenotypes was carried out by the disc diffusion method and the double disc synergy method in Mueller-Hinton agar. The study of biofilm formation was performed using the tissue culture plate in Mueller-Hinton broth and Congo red agar.

Results: A total of 30 clinical isolates of Pseudomonas aeruginosa were collected from 300 patients. Pus presented the highest proportion of Pseudomonas aeruginosa followed by urine and blood with frequencies of 60%, 16,66% and 13.33% respectively. We detected 76,66% of multi-resistant Pseudomonas aeruginosa with high resistance frequencies to the majority of betalactams and the aminoglycoside, attributed to ertapenem (100%), cefotaxime (100%), tircalillin (86.66%) and tobramycin (60%). These strains presented 10% and 3.33% of carbapenemases and Extended-spectrum beta lactamases (ESBLs) respectively. According to their ability to produce biofilm, 16,66% and 83, 33% were non-biofilm formers with Plate culture method and culture method on Congo red agar respectively.

Conclusion: This study demonstrated that P. aeruginosa strains circulating in the Center region have several enzymatic mechanisms of resistance to antibiotics associated with a high production of biofilm. The study of biofilm formation shows a significant difference between the tissue culture technique and the Congo red agar culture technique.

Keywords: Pseudomonas aeruginosa; Resistance Phenotypes; Carbapenemases; ESBLs; Resistance Genes


  1. Battraud Paul. “La résistance aux antibiotiques, un mythe ou une réalité?” Thèse pour le diplome d'etat de docteur en pharmacie (2017): 1-128.
  2. Nko’o Amvene Samuel and Marie Claire Okomo Assoumou. “Antibiotiques et résistance bactérienne : un sujet de préoccupation”. Health Sciences and Disease4 (2013): 1-2.
  3. Valencia Estela Ynés., et al. “Ciprofloxacin-mediated mutagenesis is suppressed by subinhibitory concentrations of amikacin in Pseudomonas aeruginosa”. Antimicrobial Agents and Chemotherapy 3 (2017): e2107-e2116.
  4. CA-SFM. Recommendations 1 (2020): 1-9.
  5. O'Toole., et al. “Flagellar and twitching motility are necessary for Pseudomonas aeruginosa biofilm development”. Molecular Microbiology2 (1998): 295-304.
  6. , et al. “Adherence of coagulase-negative staphylococci to plastic tissue culture plates: a quantitative model for the adherence of staphylococci to medical devices”. Journal of Clinical Microbiology 22.6 (1985): 996-1006.
  7. Wenbo Hou., et al. “The Association for Research in Vision and Ophthalmology”. Investigative Ophthalmology and Visual Science 9 (2012): 5624-5631.
  8. , et al. “Detection of biofilm formation among the clinical isolates of Staphylococci: An evaluation of three different screening methods”. Indian Journal of Medical Microbiology 24.1 (2006): 25-29.
  9. François Barbier and Michel Wolff. “Multirésistance chez Pseudomonas aeruginosa Vers l’impasse thérapeutique?” Medicine/Sciences11 (2010): 960-968.
  10. Njall, pouth Clotilde., et al. “Écologie bactérienne de l’infection nosocomiale au service de réanimation de l’hôpital Laquintinie de Douala, Cameroun”. Pan African Medical Journal140 (2013): 1-8.
  11. NAPA TCHUEDJI., et al. “Epidemiology of Pseudomonas aeruginosa and Its Resistance in Cameroon: Systematic Review and Meta Analysis”. Global Advanced Research Journal of Microbiology5 (2020): 069-072.
  12. Gonsu Kamga., et al. “Caractérisation phénotypique des souches de Pseudomonas aeruginosa isolées dans la ville de Yaoundé (Cameroun)”. African Journal of Pathology and Microbiology 4 (2015): 1-4.
  13. Worthington Roberta and Melander Christian. “Overcoming Resistance to β-Lactam Antibiotics”. Journal of Organic Chemistry 9 (2013): 4207-4213.
  14. Founou Raspail Carrel., et al. “Clinical and economic impact of antibiotic resistance in developing countries: A systematic review and meta-analysis”. Plos One12 (2017): e0189621.
  15. Robert Hancock Rew and Speert David. “Antibiotic resistance in Pseudomonas aeruginosa: mechanisms and impact on treatment”. Drug Resistant Update4 (2000): 247-255.
  16. Madaha Estelle Longla., et al. “Occurrence of blaTEM and blaCTXM Genes and Biofilm-Forming Ability among Clinical Isolates of Pseudomonas aeruginosa and Acinetobacter baumannii in Yaoundé, Cameroon”. Microorganisms 708 (2020): 1-22.
  17. Kengne Landry. “Contribution à la lutte contre les contaminants microbiens des locaux et des collections des bibliothèques au moyen d’huiles essentielles”. Thèse de Doctorat. Université de Yaoundé I. Cameroun (2019): 1-236.


Citation: Yves Le Grand Napa Tchuedji., et al. “Study of Resistance Mechanisms and Evaluation of Biofilm Detection Tests in Clinical Isolates of Pseudomonas aeruginosa Circulating in Yaounde, Cameroon". Acta Scientific Microbiology 4.12 (2021): 104-110.


Copyright: © 2021 Yves Le Grand Napa Tchuedji., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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