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

The antimicrobial susceptibility pattern of Staphylococcusaureus in Umuahia was investigated in this study.A total of 113 strains of S. aureus consisting 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 susceptibilityFrench AbstractLe 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 au

Evaluation Of The Quality Of Locally Manufactured Antimicrobial Susceptibility Testing Discs Used In South Eastern Nigeria

Locally manufactured antimicrobial susceptibility discs are becoming increasingly used in both private and government hospital laboratories in Nigeria. Data on the quality of these locally manufactured antimicrobial discs are not available. In order to provide some data, we evaluated the quality of three brands of locally manufactured antimicrobial susceptibility discs in common use in southeastern Nigeria. The three brands are Brodisk, Jirehdisk and Optudisc. The performances of these brands in agar disc diffusion assay against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were compared with that of Abtek, the imported brand. Un-interpretable zones of inhibition defined as large zones of inhibition that merged together or complete wiping out of bacterial growth at the time of reading of the plate, were common with Optudisc and Jiredisk brands. The imported brand, Abtek, did not produce any such results. While Gentamycin on Abtek produced a mean diameter of zone of inhibition of 15mm, 19mm and 16mm against S. aureus, P. aeruginosa and E. coli respectively, the same antibiotic disc with the same stated potency on Brodisk an Jiredisk produced no zone of inhibition against the test bacteria. Amoxylin and Augmentin discs on Abtek produced zones of inhibition of 13mm and 21mm against S. aureus respectively. Amoxylin disc on Brodisk did not produce any zone of inhibition against the bacterial strain while Augmentin disc on Jirehdisk produced un-interpretable result. Of the three locally made brands, Brodisk is the only one that conformed to the international standard of not having more than eight discs per 90mm plate. In our opinion, Brodisk can be recommended for clinical use in Nigeria with further improvement. The outcome of this study indicates the need for improved standardization in the production of these locally manufactured susceptibility discs. African Journal of Clinical and Experimental Microbiology Vol. 9 (3) 2008: pp. 122-12

Case-Detection Rate of Direct Sputum Smear Microscopy for Diagnosis of Pulmonary Tuberculosis in Abia State, Nigeria

The accuracy of sputum smear microscopy, the tuberculosis case-finding method in the Abia State TB Control Programme has never been assessed due to lack of culture facilities. To assess the accuracy of sputum smear microscopy in routine control programme conditions in Abia State, sputum samples from patients undergoing investigation for tuberculosis were analyzed using Ziehl-Neelsen staining technique for sputum smear  microscopy and culture on Löwenstein-Jensen medium as reference standard. Out of 150 participants tested, 51 were smear –positive for acid fast bacilli (positivity rate, 34.0 %, 51/150) while 79 were culture positive for Mycobacterium tuberculosis complex and 12 for non-tuberculous mycobacteria (NTM). Thirty-seven of the 79 culture positive for M. tuberculosis were smear positive giving a ratio of smear to culture positivity of 46.84%. Forty-two (42.4%) of the 99 smear negative cases were culture positive for M. tuberculosis. The sensitivity of smear microscopy was 50.0%(95%CI=39.0-61.0) and specificity was 92.3% (95% CI=86.4-98.2). The prevalence of HIV/TB coinfection among the study participants was 48% (12/25). Although the case- detection rate of smear microscopy was moderate in this study, the large proportion of TB patients missed by smear microscopy is a cause for concern and requires concerted effort to improve the sensitivity of smear microscopy. Introduction of more sensitive diagnostic methods like culture also need to be considered. La précision des frottis, la méthode la recherche de cas de tuberculose  dans le programme de lutte contre la tuberculose dans l’Etat d'Abia n'a jamais été évalué en raison du manque d'installations de culture. Pour évaluer la précision des frottis dans les conditions du programme de  contrôle de routine dans cet Etat , les expectorations de patients subissant une enquête de la tuberculose ont été analysées à l'aide de technique de coloration de Ziehl-Neelsen pour la microscopie des frottis de crachats etde la culture sur milieu de Löwenstein- Jensen en tant que norme de  référence . Sur les 150 participants testés, 51 étaient à frottis positif pour les bacilles acido rapide (taux de positivité, 34,0%, 51/150), tandis que 79 étaient positifs à la culture pour complexe Mycobacterium tuberculosis et 12 pour les mycobactéries non tuberculeuses (NTM). Trente-sept de la culture 79 positive pour M.tuberculosis étaient à frottis positif donnant un ratio de frottis de positivité de la culture de 46,84 %. Quarante-deux  (42,4%) des 99 cas à frottis négatifs étaient positifs à la culture pour M. tuberculosis. La sensibilité de la microscopie des frottis était de 50,0 % (IC à 95% = 39,0 à 61,0) et la spécificité était de 92,3 % (IC à 95% = 86,4 à 98,2). La prévalence du VIH / TB coïnfection parmi les participants à l'étude était de 48% (12 /25). Bien que le taux de microscopique des  frottis de dépistage des cas ait été modéré dans cette étude, la forte proportion de patients atteints de tuberculose manqués par examen microscopique des frottis est un sujet préoccupant et exige un effort concerté pour améliorer la sensibilité de la microscopie des frottis. La présentation des méthodes de diagnostic plus sensibles comme la culture doivent aussi être pris en considération

Assessment of the Diagnostic Potential of Clinotech TB Screen Test for Diagnosis of Pulmonary Tuberculosis in Nigeria

The Clinotech TB Screen test, a 3rd generation multi-antigen rapid chromatographic immunoassay for detection of IgG antibodies in serum against recombinant protein antigens 38kDa, 16kDa and 6kDa, was assessed for its diagnostic potential for diagnosis of active pulmonary TB in routine TB control programme in Abia State, Nigeria. The overall sensitivity and specificity of Clinotech TB Screen test were 24.1% and 87.8% (95% Confidence intervals [CI]: 14.7-33.5% and 80.6-95.0%) respectively. The positive and Negative Predictive Values (PPV and NPV) were 79.2% and 37.5% respectively. The performance of the test was inferior to that of the sputum smear microscopy which had a sensitivity of 50.0% (95% CI, 39.0%-61.0%) and specificity of 92.3(95% CI: 86.4-98.2%). In 37 culture positive smear positive PTB cases, Clinotech TB Screen test was positive in 18(48.65%). The rapid test showed a very low degree of sensitivity in smear –negative culture positive PTB cases; detecting just one (2.38%) out of 42 cases. These results indicate that the diagnostic value of Clinotech TB Screen test for routine diagnosis of PTB in this setting is limited.Key words: Tuberculosis, serological tests, immunochromatographic tests, rapid TB test

Phytochemical and antimicrobial properties of Solanum macranthum Dunal

Extracts of leaves, stem bark, roots and fruits of Solanum macranthum Dunal were subjected to preliminary phytochemical screening for the presence of plant secondary metabolites and in vitro antibacterial and antifungal studies respectively. The results of the preliminary investigation revealed the presence of alkaloids, the steroidal nucleus, saponins, tannins, cardiac glycosides, flavonoids, reducing sugars and  anthraquinones. The in vitro antimicrobial activity was done using agar well diffusion technique. Six clinical strains of human pathogenic  microorganisms, comprising two Gram positive, two Gram negative bacteria and two fungi were utilized in the studies. The various plant extracts varied in their high inhibitory activity to Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli at 1000 mg/ml comparable to the  reference antibacterial drug, gentamicin at 2.5 mg/ml. High activity was exhibited against Bacillus subtilis whilst Candida albicans and Aspergillus niger were moderately inhibited even at 2000 mg/ml.Key words: Solanum macranthum, Solanaceae, antimicrobial activity, phytochemical screening

Uptake of Cervical Cancer Screening Services Among Female Medical Practitioners in Ogun State, South-West Nigeria

Background: There is an increasing awareness of cancer screening services in the general population, but the uptake of the services varies. Objective: To determine the uptake of cervical cancer screening services among female medical doctors as service providers. Methods: This was a questionnaire-based, cross-sectional, descriptive study of female doctors practising in Ogun State, Nigeria. The questionnaires were self-administered, and convenience sampling method was used. Results: A total of 85 female doctors were surveyed. A little over half of the respondents (57.6%) reported routine medical checks and 54.2% of the respondents had a check up in the last two years. Seventy percent of the respondents who had a routine medical check-up and screening for cervical cancer were within the age range 31-50 years, and there were significant relationships between age and routine medical check-up and screening for cervical cancer (p values =0.014 and 0.005 respectively. Thirty-three of the respondents (39.8%) had ever been screened for cervical cancer while only 30.1% of the respondents had been screened for cervical cancer in the last three years. The majority of the respondents (59.8%) did not approve of making cervical cancer screening a condition for social benefits. Conclusion: Female medical doctors had a low uptake rate for cervical cancer screening services. The low uptake may adversely affect the cervical cancer screening campaigns targeted at the general population. Mandatory cervical cancer screening, as a prerequisite for social benefit, may improve the uptake rates for the screening services

Microbial flora associated with the soils of edible snail farms in Southern Nigeria

Microbial analysis of soil samples collected from snail farms in two different locations (Ughelli, Delta State and Obokofia, Imo State) in southern Nigeria were carried out and compared with that of soil samples collected from ordinary farmlands in these locations.The snail species encountered in this study were Achatina achatina and Archachatina marginata, which are the popular species of economic interest in Nigeria. Analysis of snail farm soil indicated a high number of heterotrophic bacteria (7.20x105 to 9.60x105 cfu/g) than the farmland soil (1.06x105 to 4.40x105 cfu/g). The snail shell effluent contained 1.9x105 to 2.28x105 cfu/ml. Coliform bacteria was 1200 MPN/100g in the snail farm soil, 260 MPN/100g in the unimpacted farmland soil, 480 MPN/100ml in the visceral mass and 160MPN/100ml in the sail shell effluent. Counts of Vibrios recorded were in the ranges of 1.80x104 to 3.2x104 cfu/g for the snail farm soil, 4.0x104 to 2.70x105cfu/ml in the snail shell affluent and 0 to 1.30x104 cfu/ml in the visceral mass. None was recorded in the unimpacted farmland soil. Staphylococcus species was in the range of 1.48x103 to 2.6x103 to 1.6x10 4 cfu/ml in the snail shell effluent and 2.40x10 to 4.8x10cfu/ml in the visceral mass. Pseudomonas/Aeromonas species were low in number in the farmland soil (0 to 1.06x102 cfu/g), snail farm soil (1.1x103 to 2.1x103cfu/g), snail shell effluent (7.1x102 to 2.20x103 cfu/ml) and visceral mass (2.69x102 to 3.2x102 cfu/ml).Other bacterial genera isolated from the farms included Salmonella, Escherichia coli, Bacillus, Klebsiella, Streptococcus and Proteus, and these occurred in higher numbers than in the unimpacted farmland soil. Nigerian Journal of Soil Science Vol. 15 2005: 75-8