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Characterization of biofilm formation in clinical urinary isolates of Staphylococcus aureus from five hospitals in Lagos State, Nigeria

 1Orjih, C. I., 2Ajayi, A., 1,3Alao, F. O., 1Adeleye, A. I., and *2,4Smith, S. I.  

 1Department of Microbiology, University of Lagos, Akoka, Nigeria

2Molecular Biology and Biotechnology Department, Nigerian Institute of Medical Research, Lagos, Nigeria

3Department of Biological Sciences, Bells University of Technology, Ota, Ogun State, Nigeria                       

4Mountain Top University, Lagos-Ibadan Expressway, Ogun State, Nigeria

*Correspondence to: stellaismith@yahoo.com                              

Abstract:                                                                                               

Background: Biofilm formation by pathogens is of great clinical importance as it mediates persistence and resistance to antibiotics, hence posing difficulty in treatment and management of diseases. The aim of this study was to evaluate the biofilm forming potential of Staphylococcus aureus isolated from urine samples of females with urinary tract infection and to detect the presence of clumping factor (clfA) and intracellular adhesion (icaA) encoding genes.                                                           

Methodology: A total of 50 S. aureus were obtained from urine samples of women in five hospitals in Lagos State, Nigeria. Isolates were confirmed by standard biochemical and novobiocin susceptibility tests. The isolates were screened for biofilm formation using three methods; Congo-red agar (CRA), tube, and tissue culture plate (TCP) methods. Detection of clfA and icaA genes was done by PCR.          Continue reading “Characterization of biofilm formation in clinical urinary isolates of Staphylococcus aureus from five hospitals in Lagos State, Nigeria”

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Klebsiella pneumoniae producing extended spectrum β-lactamase in Regional Military University Hospital of Oran, Algeria: antibiotic resistance, biofilm formation, and detection of blaCTX-M and blaTEM genes

*1Benbrahim, C., 1Barka, M. S., 2Benmahdi, L., 3Zatout, A., and 1Khadir, A.

1Laboratory of Applied Microbiology in Food, Biomedical and Environment (LAMAABE), Department of Biology, Faculty of Nature and Life, Earth and Universal Sciences, Abou Bekr Belkaid University, 13000 Tlemcen, Algeria

2Laboratory of Microbiology, Regional Military University Hospital, Oran, Algeria

3Laboratory of Microbiology and Plant Biology, Department of Biological Sciences, Faculty of Natural Sciences and Life, University of Abdlhamid Ibn Badis, Mostaganem, Algeria

*Correspondence to: chahla.benbrahim@univ-tlemcen.dz

Abstract:
Background: Klebsiella pneumoniae is a bacterial pathogen commonly associated with severe nosocomial and community acquired infections especially through the acquisition of extended spectrum β-lactamases (ESβL) and biofilm formation capacity. The objectives of this study are to determine the prevalence of K. pneumoniae ESβL (KP-ESβL)-producing isolates in the Regional Military University Hospital of Oran (HMRUO) Algeria, characterize their antibiotic resistance profile, genetically detect blaTEM and blaCTX-M genes, and evaluate their biofilm formation capacity. Continue reading “Klebsiella pneumoniae producing extended spectrum β-lactamase in Regional Military University Hospital of Oran, Algeria: antibiotic resistance, biofilm formation, and detection of blaCTX-M and blaTEM genes”

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Infections of implantable cardiac devices by biofilm forming bacteria in western Algeria hospitals

1Meziani, Z., 1Hassaine, H., and 2Belhachemi, F.

1Laboratory of Applied Microbiology in Food, Biomedical and Environment (LAMAABE), University of Tlemcen, Algeria

2Department of Cardiology, Hospital of Tlemcen, Algeria

*Correspondence to: zahera_fd@yahoo.fr; 00213553406801

Abstract:

Background: The significant increase in the use of implantable cardiac devices (ICDs) has been accompanied by biofilm formation and increase rate of infection on the devices. The purpose of our study is to describe the clinical and microbiological findings of infection of ICDs in the cardiology units of western Algeria hospitals.

Methodology: All patients with clinical diagnosis of ICD infections or infective endocarditis upon removal of their ICDs from December 2012 to August 2014 in cardiology units of 4 Algerian hospitals were included in the study. Each element of the ICD pocket and lead was separately sonicated in sterile saline, inoculated onto Chapman and MacConkey agar plates and incubated aerobically at 37oC for colony count after 24 hours. Biochemical identification of the bacteria isolates was made by API 20E, API 20 NE and API Staph, and confirmed by Siemens Healthcare Diagnostics WalkAway® 96 Plus System. Antibiotic susceptibility testing on each isolate was performed by the disk diffusion method on Mueller Hinton agar. Biofilm formation was detected by Congo Red Agar (CRA) and Tissue Culture Plate (TCP) methods, and hydrophobicity of the bacterial cell was determined by the MATH protocol.

Results: Over a period of twenty-one months, 17 ICDs were removed from patients with post-operative infections; 6 (35.3%) had early infection of ICD and 11 (64.7%) had late ICD infection. Fifty-four bacterial strains were isolated and identified, with coagulase-negative staphylococci being the predominant bacteria with 46.3% (25/54). There was no significant association between hydrophobicity and antimicrobial resistance in the 54 isolates but there is positive correlation between biofilm production and antimicrobial resistance, with the strongest biofilm producers resistant to more than one antibiotic. Four independent predictors of infection of resynchronization devices were reported; reoperation, multi-morbidity, long procedure, and ICD implantation.

Conclusion: Our study is the first in Algeria to describe microbiological characteristics of ICD infection. The bacteria in the biofilm were protected, more resistant and tolerated high concentrations of antibiotics and thus played a major role in the development of ICD infections. Despite the improvements in ICD design and implantation techniques, ICD infection remains a serious challenge.

Keywords: implantable cardiac devices, staphylococci, resistance, biofilm, hydrophobicity Continue reading “Infections of implantable cardiac devices by biofilm forming bacteria in western Algeria hospitals”

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Effects of certain disinfectants and antibiotics on biofilm formation by Staphylococcus aureus isolated from medical devices at the University Hospital Center of Sidi Bel Abbes, Algeria

*1,2Kara Terki, I., 1Hassaine, H., 3Kara Terki, A., 4Nadira, B., 5Kara Terki, N., 1Bellifa, S., 1Mhamedi, I., and 1,5lachachi, M.

1Laboratory of Food, Biomedical and Environnemental Microbiology (LAMAABE)

2University of Djilali lyabes, Sidi Bel Abbes, Algeria

3University Abou Bekr Belkaid, Tlemcen, Algeria

4Ecole Supérieure de Management, Tlemcen, Algeria

5University Belhadj Chouaib Ain Temouchent, Algeria
*Correspondence to: ibti.kara@gmail.com

Abstract:

Background: Staphylococcus aureus is one of the species of bacteria most frequently isolated from medical devices. The ability to produce biofilm is an important step in the pathogenesis of these staphylococci infection, and biofilm formation is strongly dependent on environmental conditions as well as antibiotics and disinfectants used in the treatment and prevention of infections.

Methodology: In this study, 28 S. aureus isolated from medical devices at the University Hospital Center of Sidi Bel Abbes in Northwestern Algeria were tested for biofilm formation by culture on Red Congo Agar (RCA). The tube method (TM) and tissue culture plate (TCP) techniques were also used to investigate the effect of penicillin, ethanol and betadine on pre-formed biofilm.
Results: Nineteen S. aureus isolates produced biofilm on the RCA and 7 produced biofilms by the tube method, 2 of which were high producer. In addition, 9 S. aureus isolates produced biofilm on polystyrene micro-plates, and in the presence of penicillin and ethanol, this number increased to 19 and 11 biofilm producing S. aureus isolates respectively. On the other hand, no biofilm was formed in the presence of betadine.

Conclusion: It is important to test for biofilm formation following an imposed external constraint such as disinfectants and antibiotics in order to develop new strategies to combat bacterial biofilms but also to better control their formation.

Keywords : Staphylococcus aureus, biofilm, medical device, disinfectant, antibiotic

Continue reading “Effects of certain disinfectants and antibiotics on biofilm formation by Staphylococcus aureus isolated from medical devices at the University Hospital Center of Sidi Bel Abbes, Algeria”

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Coagulase negative staphylococci in Anti-Cancer Center, Batna, Algeria: antibiotic resistance pattern, biofilm formation, and detection of mecA and icaAD genes

1*Zatout, A., 2Djibaoui, R., 2Kassah-Laouar, A., and 3Benbrahim, C.
1Laboratory of Microbiology and Plant Biology, Department of Biological Sciences, Faculty of Natural Sciences and Life, University of Abdlhamid Ibn Badis, Mostaganem, Algeria
2Central Laboratory of Biology, Anticancer Center of Batna, Algeria
3Laboratory of Microbiology Applied to the Agroalimentary Biomedical and the Environment, Department of Biology, Faculty of Natural Sciences and Life, University Abou BekrBelkaid, Tlemcen, Algeria
*Correspondence to: asma.zatout@univ-mosta.dz

Abstract:
Background: Coagulase-negative staphylococci (CoNS) are normal microbial flora found on the skin and mucous membranes of mammals. Considered for a long time as avirulent commensals, these bacteria are now recognized as opportunistic pathogens by virtue of their high resistance to multiple antibiotics and capacity for biofilm formations, which made them important agents of nosocomial and community-acquired infections. The objectives of this study are to determine the antibiotic resistance pattern and biofilm formation, and to detect mecA and icaAD genes in clinical CoNS isolates from Batna’s Anti-Cancer Center (ACC) in Algeria. Methods: A total of 66 CoNS were isolated from different samples and identified by API Staph system. In vitro antibiotic susceptibility testing (AST) of each isolate to selected antibiotics was determined by the disk diffusion method, and minimum inhibitory concentrations (MICs) of oxacillin and vancomycin were determined by E-test. Biofilm formation was assessed by Tissue Culture Plate (TCP) and Congo Red Agar (CRA) methods. The polymerase chain reaction (PCR) was used to amplify mecA gene in 9 oxacillin-resistant and 1 oxacillin-sensitive CoNS, and icaAD gene in 9 biofilm forming and 1 non-biofilm forming CoNS. Sequencing of the 16S rDNA of 1 mecA and 1 icaAD positive isolates was performed by the Sanger method. Results: Nine species of CoNS were identified, with Staphylococcus epidermidis (n=29, 44%) and Staphylococcus haemolyticus (n=15, 22.7%) constituting the largest proportion, and isolated mainly from the onco-haematology service unit of the center. The isolates were resistant to penicillin G (98.5%), cefoxitin (80.3%) and oxacillin (72.2%). The TCP method was more sensitive (89.4%) than CRA method (31.8%) in detecting biofilm formation. The mecA gene was detected in 66.7% (6/9) of oxacillin resistant CoNS and the icaAD gene in 55.6% (5/9) of TCP positive CoNS isolates Conclusion: Invitro resistance to methicillin (oxacillin) and biofilm formation were high among the CoNS isolates in this study, but the association of these with respective carriage of mecA and icaAD genes was low.

Keywords: Coagulase negative staphylococci, identification, antibiotic resistance, biofilm, PCR

Received April 26, 2019; Revised October 2, 2019; Accepted October 5, 2019
Copyright 2020 AJCEM Open Access. This article is licensed and distributed under the terms of the Creative Commons Attrition 4.0 International License (//creativecommmons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium, provided credit is given to the original author(s) and the source.

Staphylocoques à coagulase négative au Centre Anti-Cancer du Batna, Algérie: résistance aux antibiotiques, formation de biofilms et détection des gènes mecA et icaAD

1*Zatout, A., 2Djibaoui, R., 2Kassah-Laouar, A., et 3Benbrahim, C.
1Laboratoire de Microbiologie et Biologie Végétale, Département des Sciences Biologiques, Faculté des Sciences de la Nature et de la Vie, Université Abdlhamid Ibn Badis, Mostaganem, Algérie
2Laboratoire Central de Biologie, Centre Anti-Cancer (ACC), Batna, Algérie
3laboratoire de Microbiologie Appliquée à l’Agroalimentaire au Biomédical et à l’Environnement, Département de Biologie, Faculté des Sciences de la Nature et de la Vie, Université Abou Bekr Belkaid, Tlemcen, Algérie
Correspondance à: asma.zatout@univ-mosta.dz
Coagulase negative staphylococci in Algeria Afr J. Clin. Exper. Microbiol. 2020; 21 (1): 21-29

Abstrait :

Contexte: Les staphylocoques à coagulase négative (CoNS) sont une flore microbienne normale présente sur la peau et les muqueuses humaines des mammifères. Considérés depuis longtemps comme des commensales avirulentes, ces bactéries sont reconnues comme agents pathogènes opportunistes grâce à leurs multiples propriétés coexistantes de résistance aux antibiotiques et de formation de biofilms qui constituent des agents importants d’infections nosocomiales et communautaires. l’objectif de cette étude est de déterminer la résistance aux antibiotiques, la formation de biofilms et pour rechercher des gènes mecA et icaAD dans les isolats cliniques de staphylocoques à coagulase négative du Centre Anti-Cancer (AAC) de Batna en Algérie. Méthodes: au total de 66 des SCN ont été isolés de différents prélèvements et identifiés par galerie API Staph. Le test de sensibilité aux antibiotiques In vitro de chaque isolat par rapport aux antibiotiques sélectionnés a été déterminé par la méthode de diffusion sur disque, et les concentrations minimales inhibitrices (MICs) de l’oxacilline et de la vancomycine ont été déterminées par E-test. La formation de biofilm a été évaluée par la méthode de culture de tissu en plaque (TCP) et la méthode de Rouge Congo Agar (CRA). La réaction en chaîne par polymérase (PCR) a été utilisée pour amplifier l’ADN du gène mecA dont 9 des SCN résistants à l’oxacilline et 1 sensible à l’oxacilline et le gène icaAD dont 9 des SCN formant biofilm et 1 non-formant biofilm. Le séquençage de l’ADNr 16S des isolats positifs, 1 mecA et 1 icaAD ont été réalisés par la méthode de Sanger. Résultats: Neuf espèces des SCN ont été identifiées avec Staphylococcus epidermidis (n=29, 44%) et Staphylococcus haemolyticus (n=15, 22,7%) constituant la plus grande proportion, et isolées principalement de l’unité de service d’onco-hématologie du centre. Les isolats étaient résistants à la pénicilline G (98,5%), à la céfoxitine (80,3%) et à l’oxacilline (72,2%). La méthode TCP était plus sensible (89,4%) que la méthode CRA (31,8%) dans la détection de la formation de biofilm. Le gène mecA a été détecté dans 66,7% (6/9) des SCN résistants à l’oxacilline et le gène icaAD dans 55,6% (5/9) des isolats positifs des SCN pour CRA. Conclusion: La résistance à la méthicilline (oxacilline) in vitro et la formation de biofilms étaient élevées chez les isolats des SCN de cette étude, mais leur corrélation avec le portage respectif des gènes mecA et icaAD était faible.

Mots-clés: Staphylocoque à coagulase négative, identification, résistance aux antibiotiques, biofilm, PCR

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Coagulase negative staphylococci in Anti-Cancer Center, Batna, Algeria: antibiotic resistance pattern, biofilm formation, and detection of mecA and icaAD genes

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Antibiotic resistance and ndvB gene expression among biofilm producing Pseudomonas aeruoginosa isolates

N.A. Mohammed, I.M. Abd Alla

 

Abstract

A novel antibiotic resistant mechanism among biofilms is glucan-mediated sequestration in which ndvB gene encodes a glucosyltransferase involved in the formation of this glucans. We studied the biofilm formation and antibiotic susceptibility pattern of P. aeruginosa isolated from clinical samples, and measured the expression of ndvB gene among biofilm forming isolates and their planktonic counterparts. The study was conducted on 92 P. aeruginosa isolates. Biofilm was measured using tissue culture plate method. Antibiotic susceptibility of biofilm positive isolates and planktonic counterparts for ciprofloxacin, tobramycin and gentamycin was tested using tube microdilution method. Expression of ndvB gene was measured using Syper green real time PCR. We found that 44 isolates (47.8%) of P. aeruginosa were biofilm positive. The biofilm formation was high among urine, endotracheal tube aspirate and burn isolates compared to isolates of wound specimens, with statistically nonsignificant differences. None of biofilm forming isolates was susceptible to the 3 antibiotics compared to the presence of susceptible isolates among the planktonic counterpart (18/40.9% for ciprofloxacin, 12/27.3% for tobramycin and 13/29.5% for gentamycin). Expression of ndvB gene was significantly high in biofilm isolates than their corresponding counterpart, with significant correlations with minimal biofilm inhibitory concentration (MBIC) values of cibrofloxacin (r=+ 0.65, p< 0.05 ), tobramycin (r= + 0.54 p< 0.05 ) and gentamycin (r=+ 0.77, p< 0.001 ).From this study we concluded that biofilm formation is an important character of P. aeruginosa that is a main cause of antibiotic resistance especially in isolates from catheterized urine , wound and endotracheal tube aspirate. NdvB gene expression is a mechanism of resistance to antibiotics in P. aeruginosa biofilms.

Keywords: P. aeruginosa, biofilm, antibiotic resistance and ndvB gene

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Antibiotic resistance and ndvB gene expression among biofilm producing Pseudomonas aeruoginosa isolates