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Genotypic identification of coliforms isolated from cases of subclinical mastitis among pastoral herds in parts of Kaduna State, Nigeria

1, 2*Makolo, D., 2Suleiman, A. B., 2Olonitola, O. S., 3Bello, M., and 4Ahmadu, I.

1Department of Sciences, School of Preliminary Studies, Kogi State Polytechnic, Lokoja, Nigeria

2Department of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria

3Department of Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Nigeria

4National Tuberculosis Reference Laboratory, Zaria, Nigeria *Correspondence to: makolodaniel@gmail.com

Abstract:

Background: Mastitis caused by Staphylococcus aureus was initially considered the major problem in dairy herds, but over the last few decades, the incidence of coliform mastitis has increased among the pastoral herds in Nigeria due to poor environmental and milking hygiene. Hence, this study was aimed at genotypic identification of coliform bacteria isolated from cases of bovine mastitis among pastoral herds in parts of Kaduna State, Nigeria.

Methods: A cross-sectional survey of 30 herds of cows across 7 Local Government Areas of Kaduna State, Nigeria, was conducted. One hundred and forty seven cows were proportionately selected by purposive sampling technique. The milk samples were aseptically collected and bacteriologically screened for coliform bacteria following standard bacteriological techniques. Nine out of 12 coliforms identified phenotypically were selected for PCR amplification and sequencing of their 16S rRNA gene. The Basic Local Alignment Search Tool (BLAST) analysis of the sequences obtained was done on the National Centre for Biotechnology Information (NCBI) data base, and isolates confirmed based on similarity to 16S rDNA sequences in the Gen Bank Continue reading “Genotypic identification of coliforms isolated from cases of subclinical mastitis among pastoral herds in parts of Kaduna State, Nigeria”

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Seroprevalence of Toxoplasma gondii infection and associated risk factors among pregnant women attending antenatal clinic at the Bamenda Regional Hospital, Cameroon

*1Nguemaïm, N. F., 2Takang, W. A., 2Dobgima, W. P., 2Guebidiang, B. M., 3Foumane, P., and 4Kamga, F. H. L.

1Department of Biomedical Sciences, Faculty of Health Sciences, University of Bamenda, Cameroon

2Department of Clinical Sciences, Faculty of Health Sciences, University of Bamenda, Cameroon

3Department of Obstetrics and Gynecology, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Cameroon

4Department of Medical Laboratory Science, Faculty of Health Sciences, University of Bamenda, Cameroon

*Correspondence to: ngflorema@yahoo.fr

Abstract:

Background: Toxoplasma gondii is a ubiquitous, coccidian parasite that causes toxoplasmosis. This infection, if acquired during pregnancy may result in severe damage. It affects a third of the world’s population. In many developing countries, its prevalence is unknown, and data concerning its seroprevalence among pregnant women is scarce in our study area. The objective of this study is to determine the seroprevalence of T. gondii infection and the associated risk factors among pregnant women attending the antenatal clinic (ANC) at the Bamenda Regional Hospital in Cameroon. The results obtained will be useful in giving an estimate of the prevalence among pregnant women thus informing policy on preventive measures.

Methodology: This is a descriptive cross-sectional study of pregnant women recruited between January and April 2018 using systematic random sampling technique. Socio-demographic data of participants and predisposing factors to toxoplasmosis were collected using a pretested structured questionnaire administered to them. Five milliliters of blood were collected and the serum screened for IgG and IgM antibodies against T. gondii using the cassette and buffer immunochromatographic method. The positive IgG cases were tested further by ELISA technique. Data were analyzed using SPSS version 20. Associations between variables were tested by Chi square and p value < 0.05 was considered statistically significant. Continue reading “Seroprevalence of Toxoplasma gondii infection and associated risk factors among pregnant women attending antenatal clinic at the Bamenda Regional Hospital, Cameroon”

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Biochemical and immunological characterization of haemolysin produced by Pseudomonas aeruginosa PAO1 isolated from burn wounds

*1Allam, A. A., 2El-shawadfy, A. M., 2Hassanein W. A. E., 2Hamza, E. H. A., 1Morad, E. A., 1El Shafei, M. A. E., and 3El Etriby, D. E.

1Medical Microbiology and Immunology Department, Faculty of Medicine, Zagazig University, Egypt

2Botany and Microbiology Department, Faculty of Science, Zagazig University, Egypt

3Infection Control Unit, Specialized Internal Medicine Hospital, Mansoura University, Egypt

*Correspondence to: Egyayman66@yahoo.com; 0020155777174; 00201227989609

Abstract:

Background: Infection of burn wounds by multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) is a leading cause of morbidity and mortality and remains one of the most challenging concerns for the burns unit. The aim of this study is purify and characterize the haemolysin produced by multidrug resistant P. aeruginosa PAO1 isolated from burn wounds.

Methods: Isolation and identification of P. aeruginosa from burns was done by standard bacteriological methods. P. aeruginosa PAO1 was identified by PCR amplification and sequencing of the 16S rRNA gene. The haemolysin of P. aeruginosa PAO1 was purified by 70% ammonium sulphate precipitation followed by gel filtration on Sephadex G-100, and separation by SDS-Poly Acrylamide Gel Electrophoresis. In vivo toxicity of the purified haemolysin was determined by intraperitoneal injection of Swiss albino mice, and in vitro toxin-antitoxin neutralization test was performed as previously described. Continue reading “Biochemical and immunological characterization of haemolysin produced by Pseudomonas aeruginosa PAO1 isolated from burn wounds”

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Lactobacillus sp and some fungi from termite nests on kolanut trees had mild antagonistic effects against pathogens isolated from paediatric patients

*1Afolami, O. I., 2Arogunjo, A. O., 2Oladunmoye, M. K., 3Owoyemi, O. O., 2Aribisala, J. O., 2Ajayi-Moses, O. B., 2Gabriel, P. O., 2Bhadmus, O. C., 2Wasiu, O. S., 2Arogundade, I. O., 2Aiyenuro, E. A., and 2Akinwumi, I. M.

1Department of Biological Sciences, Michigan Technological University, 49931, Houghton, MI, USA
2Department of Microbiology, Federal University of Technology, P.M.B. 704, Akure, Ondo State, Nigeria
3Department of Microbiology, Achievers University, P. M. B. 1030, Owo, Ondo State, Nigeria

Correspondence to: afolamiolufemiifeoluwa@gmail.com or oafolami@mtu.edu

Abstract:

Background: Residents in a rural suburb of Akure jettisoned antibiotic treatment; sought alternative cure to rising incidence of paediatric infections in 2017 from local herbal dealers, with many residents claiming of better treatment response. We investigated these claims since the local herbal formula included kola nut barks and ground termites.

Methodology: Microorganisms associated with termite nests on kola nut trees in the affected community were characterized and identified using standard techniques. The Kirby Bauer disk diffusion was used to evaluate the susceptibility of the bacterial isolates to selected antibiotics. Plasmid profile of multiple antibiotic resistant bacterial isolates (MDRIs) was determined by the Birnboim and Doly method while post plasmid curing antibiotic susceptibility was performed on the MDRIs against the same selected antibiotics. The microorganisms were also evaluated for possible antagonistic effects against Salmonella sp, Staphylococcus aureus and Streptococcus pyogenes isolated from paediatric patients during the period of study using previously described methods. Continue reading “Lactobacillus sp and some fungi from termite nests on kolanut trees had mild antagonistic effects against pathogens isolated from paediatric patients”

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Salinity induced apoptosis in food spoilage yeast Zygosaccharomyces bisporus

*Sharma, A., and Sharma, S. C.

Department of Biochemistry, Panjab University, Chandigarh, 160014, India

*Correspondence to: akshya.msdn@gmail.com; 9915596237

Abstract:
Background: Food spoilage is one of the most serious challenges in agriculture, and food and beverage industry, which can lead to worldwide food economic loss. The crucial organoleptic species, Zygosaccharomyces bisporus, is a highly resistant yeast fungus that can escape industrial quality check. They survive high salt environments by undergoing immediate programmed cell death (PCD), which plays an important role in mediating adaptive responses to adverse environmental conditions. Production of reactive oxygen species (ROS) prompted by salt stress is an early event in apoptosis, which in later stage is associated with prime genomic degradation.

Methodology: In this study, the tolerance mechanism to salt of Z. bisporus MTCC 4801 cells was investigated by serial dilution of exponential growth phase of the cells in 1.0M sodium chloride (NaCl) as salt stressor, and spotting on Yeast Peptone Dextrose Agar (YPDA) plates with incubation at 28oC for growth assessment and colony count. Transmission electron microscopy (TEM) was used to demonstrate characteristic ultrastructural hallmark features of apoptosis on Z. bisporus cells exposed to 1.0M NaCl at three different stress interval periods; 60, 90, and 120 minutes. Results: Growth of Z. bisporus cells on the YPDA plates was observed after 16 hours incubation period. Comparing the growths, Z. bisporus tolerated salt concentration below 1.0M NaCl but no growth was observed at 1.0M NaCl concentration indicating 1.0M NaCl to be limiting concentration for Z. bisporus growth. TEM analyses showed that treatment of Z. bisporus with 1.0M NaCl resulted in nuclear and cytoplasmic condensation, membrane blabbing, cytoskeletal distortion, and formation of apoptotic bodies. However, on prolonged stress span (90 and 120 minutes), the fungal cells were able to osmoadapt and repaired the damaged cells, resulting in lowering of the apoptotic ratio. Conclusion: These qualitative analyses contribute more insights regarding stress adaptive mechanisms in moderately halotolerant food spoilage yeast. Continue reading “Salinity induced apoptosis in food spoilage yeast Zygosaccharomyces bisporus”

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Prevalence of intestinal helminthic infections among secondary school students in Edo State, Nigeria

1Anagha, L. I., 2Inegbenosun, C. U., and *3Inegbenosun, H.

1Department of Animal Enivronmental Biology, University of Benin,Benin City, Nigeria

2Department of Animal and Environmental Biology, Ambrose Alli University, Ekpoma, Edo State, Nigeria

3Department of Periodontics, University of Benin Teaching Hospital, Benin City, Nigeria

*Correspondence to: inegbenosun190@gmail.com

Abstract:

Background: Intestinal helminthic infections are generally common in children accounting for the largest disability adjusted life years (DALYs) of all the parasitic agents. In this study, we determined the prevalence of intestinal helminthic infections among secondary school students in a semi-urban community in Edo State, Nigeria.

Methodology: A descriptive cross sectional study of 489 students from four secondary schools in Esan West Local Government Area of Edo State, Nigeria was conducted between December 2018 and July 2019. The schools were selected by stratified random sampling and all eligible students in each school were enrolled. Stool samples were collected from each student into sterile universal bottle and direct wet mount as well as formol-ether concentrated samples were examined under compound light microscope at the Animal and Environmental Biology Laboratory of the University of Benin, Benin City, Nigeria. Structured questionnaire was administered to collect data on socio-demographic and potential risk factors for helminthic infection. Data were analysed with SPSS version 22.0 and associations between variables compared using Chi square or Fischer exact test, with p<0.05 as significant value. Continue reading “Prevalence of intestinal helminthic infections among secondary school students in Edo State, Nigeria”

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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.

Corrigendum to: Afr. J. Clin. Exper. Microbiol. 2020; 21 (1): 21-29. //dx.doi.org/10.4314/ajcem.v21i1.3

There was an error made by the authors in the published article where ‘oxacillin’ instead of ‘cefoxitin’ was used in many places to report methicillin resistance in coagulase negative staphylococci. ‘Oxacillin’ should be corrected as ‘cefoxitin’ throughout the article.

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

1*Zatout, A., 2Djibaoui, R., 2Kassah-Laouar, A., et 3Benbrahim, C.

Rectificatif à: Afr. J. Clin. Exper. Microbiol. 2020; 21 (1): 21-29. //dx.doi.org/10.4314/ajcem.v21i1.3

Il y avait une erreur commise par les auteurs dans l’article publié où «oxacilline» au lieu de «céfoxitine» était utilisée dans de nombreux endroits pour signaler la résistance à la méthicilline dans les staphylocoques à coagulase négative. «Oxacilline» doit être corrigé en «céfoxitine» tout au long de l’article.

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Corrigendum : 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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Yellow fever in Nigeria: a review of the current situation

*1Adogo, L. Y., and 2Ogoh, M. O.
1Department of Biological Sciences, Faculty of Science and Technology, Bingham University, Karu, Nasarawa State, Nigeria 2Institute of Human Virology, Abuja, Nigeria *Correspondence to: adogolillian@gmail.com

Abstract:

Several African countries including Nigeria have been battling with public health challenges for decades. Nigeria is currently facing several public health emergencies including cholera, circulating vaccine-derived poliovirus infection, cerebrospinal meningitis, monkey pox, measles, Lassa fever, and Yellow fever outbreaks in some states, as well as a humanitarian crisis in the northeast region of the country. Sporadic outbreaks of Yellow fever have been occurring in the country since September 2017 involving all thirty six states of the Federation, resulting in about 90 deaths (case fatality rate of 2.2%) and 31 deaths among confirmed cases (case fatality rate of 19.0%). Although, there is currently no specific treatment for Yellow fever, vaccination with the Yellow fever vaccine provides life-long protection, and is the most important means of preventing the disease. Despite the availability of an effective vaccine, the re-emergence of Yellow fever is directly correlated with its continuous dissemination in several countries to date. Timely detection of Yellow fever and rapid response through emergency vaccination campaigns are essential for controlling outbreaks. Vector surveillance and control are important components of reducing transmission in epidemic situations. This review attempts to provide update information on the current situation of Yellow fever in Nigeria with highlights on the history, pathogenesis and diagnosis of the disease.

Key words: Yellow fever, Nigeria, Outbreaks, Mosquitoes

Received August 24, 2019; Revised September 25, 2019; Accepted September 28, 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.

Fièvre jaune au Nigéria: état des lieux

*1Adogo, L. Y., et 2Ogoh, M. O.
1Département des sciences biologiques, Faculté des sciences et technologies, Université de Bingham, Karu, État de Nasarawa, Nigéria 2Institut de virologie humaine, Abuja, Nigeria *Correspondance à: adogolillian@gmail.com Abstrait:
Plusieurs pays africains, dont le Nigéria, luttent contre des problèmes de santé publique depuis des décennies. Le Nigéria est actuellement confronté à plusieurs urgences de santé publique, y compris le choléra, une infection à poliovirus en circulation, une méningite cérébro-spinale, la variole du singe, la rougeole, la fièvre de Lassa et la fièvre jaune dans certains États, ainsi qu’une crise humanitaire dans le nord-est du pays. Des épidémies sporadiques de fièvre jaune se sont produites dans le pays depuis septembre 2017 dans les trente-six États de la Fédération, entraînant environ 90 décès (taux de létalité de 2,2%) et 31 décès parmi les cas confirmés (taux de létalité de 19,0%). Bien qu‟il n‟existe actuellement aucun traitement spécifique contre la fièvre jaune, la vaccination avec le vaccin contre la fièvre jaune offre une protection à vie et constitue le principal moyen de prévention de la maladie. Malgré la disponibilité d’un vaccin efficace, la réémergence de la fièvre jaune est directement corrélée à sa diffusion continue dans plusieurs pays à ce jour. La détection rapide de la fièvre jaune et une réponse rapide au moyen de campagnes de vaccination d’urgence sont essentielles pour contrôler les épidémies. La surveillance et le contrôle des vecteurs sont des éléments importants de la réduction de la transmission en situation épidémique. Cette revue tente de fournir des informations actualisées
sur la situation actuelle de la fièvre jaune au Nigéria, en mettant en évidence l’histoire, la pathogenèse et le
diagnostic de la maladie

Yellow fever update in Nigeria Afr. J. Clin. Exper. Microbiol. 2020; 21(1): 1 – 13

Mots-clés: fièvre jaune, Nigéria, épidémies, moustiques

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Yellow fever in Nigeria: a review of the current situation

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Fungal neonatal and infantile sepsis in Egypt: risk factors and identification of fungal isolates

1*Ahmed, S. H., 2Mokhtar, E. M., 3El-Kholy, I. M., 4El Essawy, A. K., 1El-Din, A. A., and 1Shetaia, Y. M.
1Microbiology Department, Faculty of Science, Ain Shams University, Cairo, Egypt 2Microbiology Department, Abou Al-azayem Hospital, Cairo, Egypt 3Clinical Pathology Department, Ain Shams University Specialized Hospital, Ain Shams University, Cairo, Egypt 4Microbiology Department, Ain Shams University Specialized Hospital, Ain Shams University Cairo, Egypt, *Correspondence to: sara_saifelnasr@hotmail.com; 00971563993304

Abstract:

Background: Invasive fungal diseases (IFDs) are opportunistic infections associated with significant mortality in paediatric patients, especially in those with compromised immune system and neonates with very low birth weight (VLBW). The objectives of this study are to determine the prevalence, clinical features and fungi isolates of neonatal sepsis in three hospitals in Egypt. Methodology: The study is a cross sectional survey of 176 neonates with clinical sepsis admitted to the neonatal intensive care units (NICU) of the three hospitals over a period of one year (February 2015 to January 2016). A minimum of two blood samples (collected within 24 hours) from each neonate were cultured for bacteria in automated BacT/AlerT and conventional culture bottles, while Saboraud-Brain Heart Infusion broth was inoculated for fungi culture. Positive growths from the broth were sub-cultured on Sabouraud Dextrose Agar (SDA) plates for aerobic incubation at 25oC and 37oC for 2 weeks. Identification of fungi colonies on SDA was by conventional morphology and confirmation on chromogenic agar media. Phylogenetic analysis of representative fungi isolates was done by partial nucleotide sequencing of D1-D2 domain of the large subunit rRNA gene.
Results: Of the 176 neonates, blood culture was positive for pathogens in 55 (31.3 %) samples and fungi were isolated in 26 (14.8 %); yeast (25) and mould (1). The commonly isolated yeasts were Candida albicans, Candida tropicalis, and Candida krusei representing 34.6%, 30.8% and 23.1%, respectively of the total fungi isolated. The phylogenetic analysis in comparison to Genbank data showed defined clades for Candida tropicalis, Candida parapsilosis, Candida albicans and Pichia kudriavzevii
Conclusion: This current study highlights the changing pattern of neonatal infections in Egypt caused by Candida, with increasing incidence of infections caused by non-albicans Candida species.

Key words: fungal infection, neonatal, risk factors, PCR, yeast

Received July 4, 2019; Revised September 16, 2019; Accepted September 18, 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.

Infection fongique néonatale et infantile en Égypte: facteurs de risque et identification des isolats fongiques

1*Ahmed, S. H., 2Mokhtar, E. M., 3El-Kholy, I. M., 4El Essawy, A. K., 1El-Din, A. A., et 1Shetaia, Y. M.
1Département de microbiologie, Faculté des sciences, Université Ain Shams, Le Caire, Égypte
2Département de microbiologie, Hôpital Abou Al-Azayem, Le Caire, Égypte
3Département de pathologie clinique, Hôpital spécialisé de l’Université Ain Shams, Université Ain Shams,
Le Caire, Égypte
4Département de microbiologie, Université de Ain Shams, Spécialisé Hôpital, Université Ain Shams,
Le Caire, Égypte
*Correspondance à: sara_saifelnasr@hotmail.com; 00971563993304

Abstrait:

Contexte: Les maladies fongiques invasives (IFD) sont des infections opportunistes associées à une mortalité significative chez les patients pédiatriques, en particulier ceux dont le système immunitaire est compromis et les nouveau-nés de très faible poids à la naissance (VLBW). Les objectifs de cette étude sont de déterminer la prévalence, les caractéristiques cliniques et les isolements fongiques de la sepsie néonatale dans trois hôpitaux en Égypte.
Méthodologie: L’étude est une enquête transversale menée auprès de 176 nouveau-nés présentant une septicémie clinique et admis dans les unités de soins intensifs néonatals des trois hôpitaux sur une période d’un an (de février 2015 à janvier 2016). Un minimum de deux échantillons de sang (recueillis dans les 24 heures) de chaque nouveau-né ont été cultivés pour la bactérie dans des flacons de culture automatisés BacT/AlerT et conventionnels, tandis que le bouillon Saboraud-Brain Heart Infusion a été inoculé pour la culture de champignons. Les croissances positives du bouillon ont été sous-cultivées sur des plaques de gélose Sabouraud Dextrose Agar (SDA) pour une incubation aérobie à 25°C et à 37°C pendant 2 semaines. L’identification des colonies de champignons sur la SDA a été réalisée par la morphologie conventionnelle et confirmée sur un milieu chromogène en gélose. L’analyse phylogénétique d’isolats de champignons représentatifs a été réalisée par séquençage partiel de nucléotides du domaine D1-D2 du gène de l’ARNr de grande sous-unité.
Résultats: Sur les 176 nouveau-nés, la culture de sang était positive pour les agents pathogènes dans 55 échantillons (31,3%) et les champignons ont été isolés dans 26 (14,8%); levure (25) et moisissure (1). Les levures communément isolées étaient Candida albicans, Candida tropicalis et Candida krusei, représentant respectivement 34,6%, 30,8% et 23,1% du total des champignons isolés. L’analyse phylogénétique comparée aux données de Genbank a montré des clades définis pour Candida tropicalis, Candida parapsilosis, Candida albicans et Pichia kudriavzevii
Conclusion: La présente étude met en évidence l’évolution du schéma des infections néonatales causées par Candida en Égypte, avec une incidence croissante des infections causées par des espèces de Candida non albicans.

Afr. J. Clin. Exper. Microbiol. Fungal neonatal and infantile sepsis 2020; 21 (1): 14 – 20

Mots-clés: infection fongique, néonatale, facteurs de risque, PCR, levure

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Fungal neonatal and infantile sepsis in Egypt: risk factors and identification of fungal isolates

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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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