Posted on

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”

Posted on

Nasal carriage of methicillin resistant Staphylococcus aureus among medical students of a private institution in Ilishan-Remo, Ogun State, Nigeria

*1Ajani, T. A., 1Elikwu C. J., 1Nwadike, V., 1Babatunde, T., 2Anaedobe, C. J., 1Shonekan, O., 1Okangba, C. C., 1Omeonu, A., 1Faluyi, B., 1Thompson, T. E., 1Ebeigbe, E., 3Eze, B. G., 4Ajani, M. A., 1Perelade, K., 1Amoran, M., 1Okisor, P., 1Worancha, T., 1Ayoade, J.,
1Agbeniga, E., 1Emmanuel, C., and 1Coker, C. A.

1Department of Medical Microbiology, Ben Carson School of Medicine/Babcock University Teaching Hospital, Ilishan-Remo, Ogun State, Nigeria

2Department of Medical Microbiology, University of Abuja, Federal Capital territory, Abuja, Nigeria

3Department of Histopathology, Babcock University Teaching Hospital, Ilishan-Remo, Ogun State, Nigeria

4Department of Histopathology, College of Medicine/University College Hospital, Ibadan, Oyo State, Nigeria *Correspondence to: solamustoo@yahoo.com; +2348034412609

Abstract:

Background: Nasal carriage of methicillin resistant Staphylococcus aureus (MRSA) is a major factor for its transmission especially from the health workers and medical students to their patients. There are a number of published data on the prevalence of MRSA among health workers but data on nasal colonization of medical students by MRSA are sparse in Nigeria. The objectives of this study are to determine the prevalence of nasal carriage of MRSA among medical students of the Ben Carson School of Medicine, Babcock University, Ilishan-Remo, Ogun State, Nigeria, and identify risk factors associated with this nasal carriage.

Methodology: A case control study involving 100 clinical (study group) and 100 pre- clinical (control group) medical students was undertaken between March 2018 and October 2019. Structured questionnaire was administered to obtain socio-demographic information and potential risk factors. Nasal swab was collected from each student and cultured for isolation of S. aureus by standard microbiology techniques. Phenotypic MRSA was detected by the cefoxitin 30μg disk diffusion method according to the guideline of Clinical and Laboratory Standards Institute. The mecA gene was detected by conventional polymerase chain reaction (PCR) assay.

Results: The prevalence of S. aureus nasal carriage among the study group was 14% (14/100) while the prevalence among the control group was 6% (6/100) (p=0.097). The prevalence of phenotypic MRSA among the study group was 4% (4/100) and 1% (1/100) among the control group (p=0.3687) while mecA gene was detected in 3 of the 4 (75%) phenotypic MRSA positive study participants and in the only (100%) phenotypic MRSA positive (1%) control group. Antibiotics usage without prescription, antibiotic treatment of common cold, and use of antibiotics in the previous one year, were significantly associated with MRSA carriage among the study group.

Conclusion: Although the prevalence of nasal carriage of S. aureus and MRSA among clinical and pre-clinical medical students was not statistically significant, the risk factors identified with carriage of MRSA among the study group indicates the need for antimicrobial stewardship program to reduce carriage and transmission of MRSA by medical students.

Keywords: methicillin resistant, Staphylococcus aureus, mecA gene, nasal carriage, medical students

Received March 25, 2020; Revised April 27, 2020; Accepted April 28, 2020 Copyright 2020 AJCEM Open Access. This article is licensed and distributed under the terms of the Creative Commons Attrition 4.0 International License <a rel=”license” href=”http://creativecommons.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.

Continue reading “Nasal carriage of methicillin resistant Staphylococcus aureus among medical students of a private institution in Ilishan-Remo, Ogun State, Nigeria”

Posted on

Correlation of methicillin resistance and virulence genes of Staphylococcus aureus with infection types and mode of acquisition in Sofia, Bulgaria

1*Gergova, R. T., 1Tsitou, V. S., 2Gergova, I. I., 1Muhtarova, A. A., and 1Mitov, I. G.
1Department of Medical Microbiology, Faculty of Medicine, Medical University of Sofia, 2 Zdrave str., 1431-Sofia, Bulgaria
2Department of Military Epidemiology and Hygiene, Military Medical Academy, Sofia, Bulgaria *Correspondence to: rtgergova@gmail.com; +35929172547

Abstract:
Background: Infections due to methicillin resistant Staphylococcus aureus (MRSA) which is the most virulent species among the staphylococci have become a global health challenge. The aim of this study was to assess the correlation of genes encoding virulence and methicillin resistance in invasive and non-invasive isolates from inpatients/outpatients with staphylococcal infections in Sofia, Bulgaria. Materials and methods: Non-duplicate S. aureus isolates were recovered from clinical samples obtained from a total of 368 in-patients with healthcare-associated infections and outpatients with community acquired infections, following overnight cultures of samples on Columbia agar with 5% sheep blood at 35°C. The isolates were presumptively identified by colony and Gram stain morphology, positive catalase reaction and plasma-coagulase test. Isolates were screened for methicillin resistance by the cefoxitin disk method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) protocol. The mecA and mecC, and 12 staphylococcal virulence genes were detected by a combination of monoplex and multiplex polymerase chain reaction (PCR) assays.
Results: The prevalence of MRSA based on carriage of mecA gene was 12%; 7.7% for outpatients and 16.2% for inpatients (p<0.05). The frequency of toxin genes detection in the staphylococcal isolates were as follows; sei (72.6%), seb (59.8%), seh (41.3%), sec (38.3%), seg (37.5%), sej (32.3%), sea (26.6%), sed (10.3%), tst (6.5%), and see (4.3%). The virulence genes, tst, sea, seb, sec, seg, seh and sei were more frequently associated with MRSA than methicillin sensitive (MSSA) strains (p<0.05). About one-third of the clinical S. aureus isolates harbored seven virulence genes; sea, seb, sec, see, seg, seh and sei, that were detected significantly more among the invasive isolates (p<0.05).
Conclusions: This study shows the occurrence of highly virulent staphylococcal isolates in our geographical region.

Key words: Staphylococcus aureus, virulence, methicillin resistance

Received May 17, 2019; Revised June 5, 2019; Accepted June 7, 2019 Copyright 2019 AJCEM Open Access. This article is licensed and distributed under the terms of the Creative Commons Attrition 4.0 International License (http://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.

Corrélation des gènes de résistance à la méthicilline et de virulence de Staphylococcus aureus avec les types d’infection et le mode d’acquisition à Sofia, Bulgarie

1*Gergova, R. T., 1Tsitou, V. S., 2Gergova, I. I., 1Muhtarova, A. A., et 1Mitov, I. G.
1Département de microbiologie médicale, Faculté de médecine,
Université médicale de Sofia, 2, Zdrave str., 1431-Sofia, Bulgarie
2Département d’épidémiologie et d’hygiène militaires, Académie de médecine militaire, Sofia, Bulgarie *Correspondence à: rtgergova@gmail.com; +35929172547

Abstrait:

Contexte: Les infections dues à Staphylococcus aureus résistant à la méthicilline (SARM) l’espèce la plus virulente parmi les staphylocoques, sont devenues un problème de santé mondial. Le but de cette étude était
Methicillin resistance and virulence genes of S. aureus Afr. J. Clin. Exper. Microbiol. 2019; 20 (4): 280-288
281
d’évaluer la corrélation des gènes qui codant pour la virulence et la résistance à la méthicilline avec des isolats invasifs ou non invasifs de patients hospitalisés/ambulatoires patients infectés par le staphylocoque dans Sofia, Bulgarie. Matériels et méthodes: Des isolats de S. aureus non dupliqués ont été récupérés à partir d’échantillons cliniques prélevés chez 368 patients atteints d’infections associées aux soins de santé et de patients ambulatoires présentant des infections acquises en communauté, après avoir effectué des cultures pendant la nuit d’échantillons sur de la gélose Columbia contenant 5% de sang de mouton à 35°C. Les isolats ont été présumés identifiés par la morphologie de la colonie et de la coloration de Gram, la réaction positive à la catalase et le test plasma-coagulase. Les isolats ont été criblés pour la résistance à la méthicilline par la méthode de la céfoxitine selon le protocole du Comité européen sur les tests de sensibilité aux antimicrobiens (EUCAST). Les gènes mecA et mecC, ainsi que 12 gènes de virulence staphylococcique ont été détectés par une combinaison de tests de réaction en chaîne de la polymérase (PCR) monoplex et multiplex. Résultats: La prévalence de SARM basée sur le portage du gène mecA était de 12%; 7,7% pour les patients ambulatoires et 16,2% pour les patients hospitalisés (p<0,05). La fréquence de détection des gènes de toxines dans les isolats de staphylocoques était la suivante: sei (72,6%), seb (59,8%), seh (41,3%), sec (38,3%), seg (37,5%), sej (32,3%), sea (26,6%), sed (10,3%), tst (6,5%) et see (4,3%). Les gènes de virulence, tst, sea, seb, sec, seg, seh et sei étaient plus fréquemment associés à SARM que les souches sensibles à la méthicilline (MSSA) (p<0,05). Environ un tiers des isolats cliniques de S. aureus portaient sept gènes de virulence; sea, seb, sec, see, seg, seh et sei, qui ont été détectés significativement plus parmi les isolats invasifs (p<0,05). Conclusion: Cela crée un risque de propagation d’isolats très virulents dans la région géographique

Mots-clés: Staphylococcus aureus, virulence, résistance à la méthicilline

Download full journal in PDF below

Correlation of methicillin resistance and virulence genes of Staphylococcus aureus with infection types and mode of acquisition in Sofia, Bulgaria

Posted on

Bacterial contamination of white coats and hands of healthcare workers at mansoura university children’s hospital, Mansoura-Egypt

N. S Gouda, A. M. Sultan, H. Eldegla, W.A Seliem

 

Abstract

Background: Transmission of hospital acquired infections (HAIs) may be associated with contamination of healthcare workers’ (HCWs) hands and white coats.
Objective: The purpose of this study was to clarify the role of HCWs’ white coats in transmitting HAIs and to determine the association between bacterial contamination of HCWs’ hands and white coats.
Methods: A total of 154 HCWs were enrolled in the study; different samples were taken from their hands and white coats. Samples were processed and both microbiological and biochemical characterization of the isolates were done using standard microbiological protocols.
Results: Up to 65.6% of hands and 61% of coats of HCWs were contaminated by microorganisms. Staphylococcus aureus was the most commonly isolated organisms from both hands and coats of HCWs (29.2%, 27.3% respectively) followed by MRSA (22.1%, 24.7% respectively).
Conclusions: The risk for contamination of hands and coats of HCWs is high in different clinical settings. In order to reduce the rate of HAIs, a strict dress protocol should be set into play to prevent cross contamination between HCWs and patients.

Keywords: contamination, HCWs, coat, hand, Staphylococcus aureus, MRSA.

 

Contamination bacterienne de manteaux blancs et de mains de soins de sante a l’hopital pour enfants de l’universite mansoura, Mansoura-Egypte

Contexte: La transmission des infections

Objectif: Le but de cette étude était de déterminer l’étendue, le type et l’association entre la contamination bactérienne des mains des travailleurs de la santé et les blouses blanches.

Méthodes: Au total, 154 travailleurs de la santé ont été inclus dans l’étude; différents échantillons ont été pris de leurs mains et des manteaux blancs. Les échantillons ont été traités et la caractérisation microbiologique et biochimique des isolats a été effectuée en utilisant des protocoles microbiologiques standard.

Résultats: Jusqu’à 65,6% des mains et 61% des couches de TS ont été contaminées par des micro-organismes. Le Staphylococcus aureusétait le plus souvent isolé des deux mains et des deux sexes (29,2%, 27,3%), suivi par le SARM (22,1%, 24,7% respectivement).

Conclusions: Le risque de contamination des mains et des couches de TS est élevé dans différents contextes cliniques. Afin de réduire le taux d’IASS, un protocole vestimentaire strict devrait être mis en place pour prévenir la contamination croisée entre les travailleurs de la santé et les patients.

Mots clés: contamination, agents de santé, manteau, main, Staphylococcus aureus, SARM

Download full journal in PDF below

Bacterial contamination of white coats and hands of healthcare workers at mansoura university children’s hospital, Mansoura-Egypt

Posted on

In-vitro antimicrobial susceptibility pattern of Staphylococcus aureus isolates in Umuahia, Abia state, Nigeria

EO Ekundayo, RN Ndubuisi

 

Abstract

The antimicrobial susceptibility pattern of Staphylococcusaureus in Umuahia was investigated in this study.A total of 113 strains of S. aureusconsisting of 30 isolates from clinical specimens obtained from 10 medical Laboratories and 83 isolates from nasal swabs of University students in Umuahia, were tested against 10 antimicrobial agents using the disc agar diffusion method. Resistance to penicillin, ampicillin, cloxacillin and tetracycline was 100% among strains isolated from clinical specimens. The clinical isolates also exhibited high rates of resistance to chloramphenicol (97%) and erythromycin (97%). Seven (23%) of these isolates were sensitive to Gentamicin and 6 (20%) to Streptomycin. Likewise, all the 83(100%) and 82 (98.8%)were resistant to penicillin and cloxacillin, respectively.Isolates from nasal passages appeared to be less resistant to chloramphenicol (54.2%), gentamicin (43.4), streptomycin (31.3%) and tetracycline (51.8%). Ampicillin did not produce any zone of inhibition against 29 (96.7%) isolates from clinical specimens and only slightly inhibited one with zone of inhibition of 8mm. Nineteen of the isolates manifested low to high level of resistance to chloramphenicol with mean zone of inhibition ranging from 15. 8± 0.7 mm to 9.8± 2.0 mm. All the isolates were completely resistant to penicillin and cloxacillin with no zone of inhibition at all. In the case of gentamicin, 5 (16.7%) had intermediate susceptibility (mean zone of inhibition 14±0 mm), 12(40%) had mean inhibition zone of 9.6±2.9 mm and 6(20%) were not inhibited. This study shows that S. aureus strains isolated from clinical specimens and healthy students in Umuahia are highly resistant to common antibiotics. This may not be unconnected with indiscriminate use of antibiotics and calls for more control and rational use of antibiotics to minimize the rate of development of resistance to other antibiotics.

Key words: Staphylococcus aureus, antimicrobial resistance, disc agar diffusion, antibiotic susceptibility

French Abstract

Le profil de sensibilité antimicrobienne de Staphylococcus aureus à Umuahia a été recherché dans cette étude. Au total, 113 souches de S. aureus composé de 30 souches provenant d’échantillons cliniques obtenus à partir de 10 laboratoires médicaux et 83 souches d’écouvillons nasaux des étudiants universitaires à Umuahia, ont été testées contre 10 agents antimicrobiens par la méthode de diffusion disque sur gélose. La résistance à la pénicilline, l’ampicilline, la cloxacilline et la tétracycline a été de 100% chez les souches isolées d’échantillons cliniques. Les souches cliniques ont également présenté des taux élevés de résistance au chloramphénicol (97%) et à l’érythromycine (97%). Sept (23%) de ces souches étaient sensibles à la gentamicine et 6 (20%) à la streptomycine. De même, tous les 83 (100%) et 82 (98,8%) étaient résistants respectivement à la pénicilline et à la cloxacilline. Les souches de voies nasales semblaient être moins résistantes au chloramphénicol (54,2%), à la gentamicine (43,4), à la streptomycine (31,3%) et à la tétracycline (51,8%). L’ampicilline n’a produit aucune zone d’inhibition contre 29 (96,7%) souches provenant d’échantillons cliniques et seulement légèrement inhibées avec une zone d’inhibition de 8mm. Dix-neuf souches ont manifesté un faible niveau élevé de résistance au chloramphénicol avec une zone d’inhibition moyenne allant de 15. 8 ± 0,7 mm à 9.8± 2,0mm. Toutes les souches étaient complètement résistantes à la pénicilline et à la cloxacilline sans zone d’inhibition. Dans le cas de la gentamicine, 5 (16,7%) souches avaient une sensibilité intermédiaire (zone d’inhibition moyenne de 14 ± 0 mm), 12 (40%) souches ont eu une zone d’inhibition moyenne de 9,6 ± 2,9 mm et 6 (20%) souches ne ont pas été inhibées. Cette étude montre que les souches de S. aureus isolées  à partir d’échantillons cliniques et des étudiants en bonne santé à Umuahia sont très résistantes aux antibiotiques courants. Cela peut ne pas être en rapport avec l’utilisation sans discernement des antibiotiques et des appels pour plus de contrôle et d’utilisation rationnelle des antibiotiques afin de minimiser le taux de développement d’une résistance à d’autres antibiotiques.

Mots clés: Staphylococcus aureus, résistance aux antimicrobiens, disque de diffusion sur gélose, sensibilité aux

Download full journal in PDF below

In-vitro antimicrobial susceptibility pattern of Staphylococcus aureus isolates in Umuahia, Abia state, Nigeria

Posted on

In vitro and in vivo antimicrobial activity of partially purified enterocin produced by Enterococcus faecalis and its application in wound healing

O.M. David, M.O. Alese, D.M. Komolafe, I.J. Adejare, O.O. Alese, A.E. Omonisi

 

Abstract

Background: The recent global upsurge in antibiotic resistance among bacteria associated with wounds has contributed to high treatment failures in wound management. Enterocin are produced by enterococci and has been reported to inhibit the growth of many bacteria including those associated with wound infections.

Objectives: In this study, antibacterial and physico-chemical properties of partially purified enterocin (PPE) from Enterococcus faecalis was determined. Also, the possible application of the enterocin in wound management was evaluated.

Materials and Methods: Eight different enterocin were tested and that with highest antibacterial (E3) was partially purified using standard methods. The molecular weight of the PPE was determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis after which the in vitro anti-Staphylococcus aureus potential of the PPE was determined.

Results: Enterocin (E3) was effective against Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter cloaca, Listeria monocytogenes and Proteus vulgaris. The activity of the E3 was very prominent at pH of 4 and 8. The molecular size of the isolated enterocin was 5.5 KDa. The photomicrograph of the skin tissue of the skin treated with partially purified enterocin for day 7showed epidermis covered by atrophic stratified squamous epithelium. A synergistic interaction was noticed when Eusol was used with the enterocin.

Conclusions: From this study, enterocin from E. faecalis has a low molecular weight and inhibited bacteria isolates from wound and also aids physiological healing of wound.The antibacterial potency of this bacteriocin indicates that it is an alternative therapeutic agent that can be employed in wound care and management.

Keywords: Enterocin, Enterococcus faecalis, wounds, bacteriocin, Staphylococcus aureus, skin

Download full journal in PDF below

In vitro and in vivo antimicrobial activity of partially purified enterocin produced by Enterococcus faecalis and its application in wound healing

Posted on

Incidence and Distribution of Multi-Drug Resistant Pathogens from Clinical Samples in a Tertiary Hospital in South-South Nigeria

O Iyoha, MY Tula

 

Abstract

Background
Antibiotics have proven to be a dynamic category of drugs in the fight against infectious bacteria. However, antibiotic
resistance is one of the greatest current challenges to the effective treatment of infections and there is every indication that
antibiotic resistance will become an even greater challenge in the future.
Methodology
Ten clinical samples with varying frequencies were analyzed for bacterial growth, antibiotic susceptibility testing and
multiple antibiotic resistances. The clinical samples includes; urine (42%), wound swab (21.33%), blood (10%), ear swab
(9.33%), catheter tip (5.33%), endocervical swab (4.67%), high vaginal swab (HVS) (2.67%), urethral swab (2.67%), pus
(1.33%) and antral aspirate (0.67%).
Results
A total of 150 bacterial isolates distributed among these ten (10) clinical samples were identified, of which Staphylococcus
aureus (30%) was the most predominant, while Klebsiella oxytoca, Citrobacter spp. and Streptococcus spp. were the least
(0.67%). These were tested for sensitivity against 9 antibiotics. The resistance rate observed was as follows; cefuroxime
(93%), ceftazidime (87%), gentamycin (79%), augmentin (70%), cloxacillin (67%), ofloxacin (54%), ciprofloxacin (51%),
ceftriaxone (38%) and ocefix (34%). One hundred and forty-three (95.3%) of the isolates showed multiple resistance against
3 – 8 antibiotics. None was resistant to as few as 1 – 2 antibiotics.
Conclusion
The high susceptibility to some antibiotics such as ceftriaxone and ocefix could be a welcoming relief, since they can be
used to address the problem of resistance in this area. There is need for nationwide surveillance programme to monitor
microbial trends and antimicrobial resistance patterns in Nigeria.

Key words: multi-drug resistant, clinical samples, Staphylococcus aureus, ocefix.

 

Contexte
Les antibiotiques se sont démontrés être une catégorie dynamique des médicaments pour lutter contre les infections
bactériennes. Cependant, la résistance aux antibiotiques est l’un des grands défis actuels pour le traitement efficace des
infections et tout porte à croire que la résistance aux antibiotiques devient un défi encore plus grand à l’avenir.
Méthodologie
Dix échantillons cliniques avec leurs grandes fréquences ont été analysés par la culture bactériennes, le teste de sensibilité
aux antibiotiques et le teste de la multirésistance aux antibiotiques. Les échantillons cliniques sont constitués de l’urine
(42%), de pus de la plaie (21,33%), de sang (10%), de prélèvement d’oreille (9,33%), d’extrémité du cathéter (5,33%), de
prélèvement d’endocervical (4,67%), de prélèvement vaginal (2,67%), de prélèvement urétral (2,67%), de pus (1,33%), de
ponctionantrale(0,67%).
Résultats
Au total, 150 souches bactériennes réparties parmi les dix (10) échantillons cliniques ont été identifiées, parmi lesquelles
Staphylococcus aureus (30%) était le plus prédominant, alors que Klebsiellaoxytoca,Citrobacter spp et Streptococcus spp
étaient les moindres (0,67%). Ils ont été testés pour la sensibilité de 9 antibiotiques. Le taux de résistance observé était le suivant: céfuroxime (93%), ceftazidime (87%), gentamicine (79%), augmentin (70%), cloxacilline (67%), ofloxacine (54%),
ciprofloxacine (51%), ceftriaxone (38%) etocefix (34%). Cent-quarante-trois (95,3%) d’isolats ont montré la multi-résistance
contre 3 à 8 antibiotiques. Aucune souche n’a été résistante à moins de 1 à 2 antibiotiques.
Conclusion
La forte sensibilité de certains antibiotiques tels que la ceftriaxone et l’ocefix pourraient être un ouf de soulagement, car ils
peuvent être utilisés pour résoudre le problème de la résistance dans cette région. Il est nécessaire pour le programme
national de surveillance pour suivre les tendances microbiennes et les situations de résistance aux antimicrobiens au
Nigeria.

Mots clés: multi-résistance aux antibiotiques, échantillons cliniques, Staphylococcus aureus, ocefix.

Article in English.

Download full journal in PDF below

Incidence and Distribution of Multi-Drug Resistant Pathogens from Clinical Samples in a Tertiary Hospital in South-South Nigeria.

Posted on

Antibacterial properties of Mangifera indica on Staphylococcus aureus

J Mushore, M Matuvhunye

 

Abstract

Antibacterial activity of Mangifera indica stem bark extracts was determined using disk diffusion, agar and broth dilution methods. In disk diffusion method, inhibition zone sizes were used to determine the susceptibility of S. aureus to the extracts. The results showed that the stem-bark extracts of M. indica have antimicrobial activity against S. aureus. Methanol extracts showed the highest inhibition zone diameter of 25 mm, followed by ethyl acetate, water and hexane extracts with inhibition zone diameter of 22 mm, 14 mm and 10 mm, respectively. The antibacterial activities of different extracts were found to be concentration dependent, in agar and broth dilution methods. The plant extracts were shown to have a MIC range of 0.62 mg/ml to 4.17 mg/ml, in agar dilution method. Results from the broth dilution method had a MIC range of 0.16 mg/ml to 1.25 mg/ml. The control (ampicillin) was however, more effective than plant extracts since only a concentration of 0.03 mg/ml in agar dilution and 0.001 mg/ml in broth dilution method were effective to inhibit the growth of S. aureus. The extracts were shown to be bacteriostatic at low concentrations. Phytochemical screening of the extracts revealed the presence of phyto-compounds such as alkaloids and tannins which are known to inhibit bacterial growth by different mechanisms from those of synthetic drugs. These phyto-constituents may be responsible for the M. indica antibacterial
activity.

Keywords: Staphylococcus aureus, antimicrobial activity, MIC, Phytochemical screening, MBC.

Download full journal in PDF below

Antibacterial properties of Mangifera indica on Staphylococcus aureus

Posted on

In vitro effect of some quinolone antibiotics on strains of Staphylococcus aureus isolated from a hospital environment

RK Obi, FC Nwanebu

 

Abstract

A total of 30 different strains of Staphylococcus aureus were isolated from some selected wards of Madonna University Teaching Hospital (MUTH), Elele, Nigeria, using blood agar and nutrient agar. All the isolates were subjected to some selected quinolones (ciprofloxacin, pefloxacin, ofloxacin, norfloxcin and sparfloxacin) to determine their antibiotic susceptibility pattern using the disk diffusion method. Ofloxacin had the highest percentage
susceptibility of 93.3%, followed by ciprofloxacin with 73.3%; pefloxacin was next with 70%, sparfloxacin 63.3%, while norfloxacin recorded the lowest percentage of 50%. The minimum inhibitory concentration (MIC) of the quinolones to the isolates was also determined. The results show that all the tested quinolones had an MIC ranging from 2.5-10mg/ml.

Keywords: Staphylococcus aureus, quinolones, hospital environment

African Journal of Clinical and Experimental Microbiology Vol. 9 (3) 2008: pp. 142-146

Posted on

Pattern of resistance to vancomycin and other antimicrobial agents in staphylococcal isolates in a university teaching hospital

BO Olayinka, AT Olayinka, JA Onaolapo, PF Olurinola

 

Abstract

Multidrug resistance has been reported in clinical isolates of both coagulase-negative staphylococci (CoNS) and Staphylococcus aureus that are most often resistant to oxacillin/methicillin. Vancomycin, a glycopeptide is the drug of choice for infections caused by such multidrug resistant strains. This study determined the pattern of resistance to vancomycin and other antimicrobial agents in staphylococcal isolates from a University Teaching Hospital. Staphylococcal isolates from clinical specimens submitted to the diagnostic medical microbiology laboratory of the Ahmadu Bello University Teaching Hospital, Zaria (over a three-month period) were characterized using standard microbiological procedures and their susceptibility to vancomycin and other commonly used antimicrobial agents determined by Kirby-Bauer-NCCLS modified disc diffusion technique. A total of 56 of the 97 (57.7%) staphylococcal isolates characterized were resistant to vancomycin 30μg, showing a zone of inhibition less than 15mm. Most of these isolates were from urine (27.3%), wound (21.8%) and pleural aspirate (12.8%). The 56 staphylococcal isolates were made up of 75% (41/56) Staphylococcus aureus and 25% (14/56) coagulase-negative staphylococci. Majority of the isolates, 60.7% (34/56) produced β-lactamase enzyme. Resistance pattern to other antimicrobial agents was benzyl penicillin G (92.9%); tetracycline (69.6%); cefuroxime (60%); chloramphenicol (54.5%); oxacillin (49.1%); erythromycin (35.7%); gentamicin (25%) and ciprofloxacin (16.1%). Analysis of the multiple antibiotic resistance index (MARI) showed that majority (91.1%) were resistant to 3 to 7 of the other antimicrobial agents tested. No isolate was resistant to all the tested antimicrobial agents. A very high proportion of the staphylococcal isolates were resistant to vancomycin, a glycopeptide that is not commonly used in this environment. Ciprofloxacin and gentamicin appear to be the only agents that will be effective in treating infections by these isolates. The high proportion of isolates with MARI of 0.3 and above, suggest that the isolates originated from an environment where antibiotics are often used. There is need for constant, on-going antimicrobial resistance surveillance in important and commonly isolated clinically significant pathogens to form the basis for developing and implementing measures that will reduce the burden of antimicrobial resistance.

Key Words: vancomycin, methicillin resistance, Staphylococcus aureus, coagulase-negative staphylococci, antimicrobial agents

Afr. J. Clin. Exper. Microbiol. Vol.6(1) 2005: 21-27