Antibiotic susceptibility of campylobacter isolates from sewage and poultry abattoir drain water

SummaryIn this study, thein vitrosusceptibility of 209 campylobacter strains to the quinolones nalidixic acid, flumequine, ciprofloxacin, enrofloxacin, and to ampicillin, tetracycline and erythromycin was tested by the disk diffusion method. The strains were isolated from poultry abattoir effluent (DWA) and two sewage purification plants (SPA and SPB). Sewage purification plant SPA received mixed sewage, including that from a poultry abattoir, whereas SPB did not receive sewage from any meat-processing industry. The quinolone resistance of the DWA isolates ranged from 28% for enrofloxacin to 50% for nalidixic acid. The strains isolated from the sewage purification plants were more susceptible to the quinolones with a range of 11–18% quinolone resistance for SPB isolates to 17–33% quinolone resistance for SPA isolates. The susceptibility criteria as recommended by National Committee Clinical Laboratory Standards (USA) cannot readily be employed for campylobacter isolates. This investigation shows that the resistance of campylobacter bacteria is highest in the plant receiving sewage from a poultry slaughterhouse. Monitoring of antibiotic resistance of aquaticCampylobacterspp. is important, as surface waters are recognized as possible sources of infection.

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Comparison of antimicrobial susceptibilities of Corynebacterium species by broth microdilution and disk diffusion methods.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.4.930 ◽

1996 ◽

Vol 40 (4) ◽

pp. 930-933 ◽

Cited By ~ 29

Author(s):

K Weiss ◽

M Laverdière ◽

R Rivest

Keyword(s):

Clinical Laboratory ◽

High Rate ◽

Disk Diffusion ◽

Diffusion Method ◽

National Committee ◽

Broth Microdilution ◽

Disk Diffusion Method ◽

Corynebacterium Species ◽

Broth Microdilution Method

Corynebacterium species are increasingly being implicated in foreign-body infections and in immunocompromised-host infections. However, there are no specific recommendations on the method or the criteria to use in order to determine the in vitro activities of the antibiotics commonly used to treat Corynebacterium infections. The first aim of our study was to compare the susceptibilities of various species of Corynebacterium to vancomycin, erythromycin, and penicillin by using a broth microdilution method and a disk diffusion method. Second, the activity of penicillin against our isolates was assessed by using the interpretative criteria recommended by the National Committee for Clinical Laboratory Standards for the determination of the susceptibility of streptococci and Listeria monocytogenes to penicillin. Overall, 100% of the isolates were susceptible to vancomycin, while considerable variations in the activities of erythromycin and penicillin were noted for the different species tested, including the non-Corynebacterium jeikeium species. A good correlation in the susceptibilities of vancomycin and erythromycin between the disk diffusion and the microdilution methods was observed. However, a 5% rate of major or very major errors was detected with the Listeria criteria, while a high rate of minor errors (18%) was noted when the streptococcus criteria were used. Our findings indicate considerable variations in the activities of erythromycin and penicillin against the various species of Corynebacterium. Because of the absence of definite recommendations, important discrepancies were observed between the methods and the interpretations of the penicillin activity.

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In vitro activity of glycopeptides against clinical isolates of Entercocci from a tertiary care hospital

Annals of King Edward Medical University ◽

10.21649/akemu.v12i1.817 ◽

2016 ◽

Vol 12 (1) ◽

Author(s):

Muhammad Tahir Majeed Tahir Majeed ◽

Mateen Izhar

Keyword(s):

Clinical Laboratory ◽

Tertiary Care ◽

Clinical Isolates ◽

Diffusion Method ◽

Medical Institute ◽

National Committee ◽

Care Hospital ◽

Glycopeptide Antibiotics ◽

Disk Diffusion Method

Objective: The objective of this study was to establish the prevalence of glycopeptide (vancomycin and teicoplanin) resistance among clinical isolates of enterococci in Shaikh Zayed Hospital, Lahore, and comparison of antimicrobial sensitivities of vancomycin and teicoplanin among these isolates. Design: A comparative analytical study. Place of study: This study was conducted in the Department of Microbiology, Federal Postgraduate Medical Institute, Shaikh Zayed Hospital, Lahore. Materials and methods: 60 (Sixty) enterococci isolates were collected from clinical specimens received in the laboratory. Identification of these bacteria was done utilizing standard laboratory operating procedures. Their sensitivity to glycopeptide antibiotics was tested by disk diffusion method in accordance with the National Committee for Clinical Laboratory Standards (NCCLS) guidelines. Results: Results show that all enterococci were sensitive to teicoplanin. However, among these isolates 1.7% resistance to vancomycin was detected. Conclusion: The results indicate that resistance to glycopeptide antibiotics in the test organisms is low in our hospital. The presence of vancomycin resistance in 1.7% clinical enterococcal isolates necessitates strict surveillance of these organisms, institution of effective infection control policies and judicious use of antibiotics.

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Detection of Decreased Fluoroquinolone Susceptibility in Salmonellas and Validation of Nalidixic Acid Screening Test

Journal of Clinical Microbiology ◽

10.1128/jcm.37.11.3572-3577.1999 ◽

1999 ◽

Vol 37 (11) ◽

pp. 3572-3577 ◽

Cited By ~ 101

Author(s):

Antti Hakanen ◽

Pirkko Kotilainen ◽

Jari Jalava ◽

Anja Siitonen ◽

Pentti Huovinen

Keyword(s):

Nalidixic Acid ◽

Clinical Laboratory ◽

Clinical Importance ◽

Acid Resistance ◽

Great Majority ◽

Diffusion Method ◽

National Committee ◽

Disk Diffusion Method ◽

Similar Association ◽

Nalidixic Acid Resistance

We evaluated 1,010 Salmonella isolates classified as fluoroquinolone susceptible according to the National Committee for Clinical Laboratory Standards guidelines for susceptibility to nalidixic acid and three fluoroquinolones. These isolates were divided into two distinct subpopulations, with the great majority (n = 960) being fully ciprofloxacin susceptible and a minority (n = 50) exhibiting reduced ciprofloxacin susceptibility (MICs ranging between 0.125 and 0.5 μg/ml). The less ciprofloxacin-susceptible isolates were uniformly resistant to nalidixic acid, while only 12 (1.3%) of the fully susceptible isolates were nalidixic acid resistant. A similar association was observed between resistance to nalidixic acid and decreased susceptibility to ofloxacin or norfloxacin. A mutation of the gyrA gene could be demonstrated in all isolates for which the ciprofloxacin MICs were ≥0.125 μg/ml and in 94% of the nalidixic acid-resistant isolates but in none of the nalidixic acid-susceptible isolates analyzed. Identification of nalidixic acid resistance by the disk diffusion method provided a sensitivity of 100% and a specificity of 87.3% as tools to screen for isolates for which the MICs of ciprofloxacin were ≥0.125 μg/ml. We regard it as important that microbiology laboratories endeavor to recognize these less susceptibleSalmonella strains, in order to reveal their clinical importance and to survey their epidemic spread.

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Drug sensitivity pattern of Escherichia coli isolated from samples of different biological and environmental sources

Bangladesh Journal of Veterinary Medicine ◽

10.3329/bjvm.v6i1.1332 ◽

1970 ◽

Vol 6 (1) ◽

pp. 13-18 ◽

Cited By ~ 4

Author(s):

MA Zinnah ◽

MH Haque ◽

MT Islam ◽

MT Hossain ◽

MR Bari ◽

...

Keyword(s):

Drug Sensitivity ◽

Clinical Laboratory ◽

Intermediate Phase ◽

Sensitivity Test ◽

Diffusion Method ◽

National Committee ◽

E Coli ◽

Sensitivity Pattern ◽

Human Faces

A total of 100 different E. coli isolates collected from 10 different biological and environmental sources (10 isolates from each source) such as human faces, human urine, cattle, sheep, goat, chicken, duck, pigeon, drain sewage and soil were used for in-vitro drug sensitivity test in the Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh during the period from January to May 2007. Ten different drugs such as Gentamicin (GM), Azithromycin (AZM), Erythromycin (E), Levofloxacin (LVX), Ciprofloxacin (CIP), Tetracycline (TE), Amoxicillin (A), Ampicillin (AP), Nalidixic acid (NA) and Metronidazole (MET) were used in this study. Sensitivity test was carried out by the Kirby-Bauer disc diffusion method as per recommendation of National Committee for Clinical Laboratory Standards and efficacy of a drug was determined by measuring the diameter of the zone of inhibition that results from diffusion of the agent in to the medium surrounding the disc. A high of 80% and 78% E. coli isolates collectively from all the selected sources were sensitive to LVX and CIP respectively, followed by GM (46%), AZM (45%), TE (30%), AP (29%), E (19%), NA (18%) and A (15%). No isolate was sensitive to MET (0%). Incase of resistance, 96% isolates were resistant to MET, followed by A (72%), E (69%), NA (67%), TE (60%), AP (59%), AZM (33%) and GM (32%), CIP (8%) and LVX (5%). A number of isolates showed intermediate reaction to GM (22%), AZM (22%), LVX (15%), NA (15%), CIP (14%), A(13%), AP (12%), E (12%), TE (10%) and MET (4%). This may be an intermediate phase for the conversion of E. coli isolates from sensitive to resistant form. From the research it may be concluded that E. coli infection of different animals and birds and also of human being may be treated effectively with LVX and CIP followed by GM and AZM. Key words: E. coli isolates, levofloxacin, ciprofloxacin, efficacy, resistance DOI = 10.3329/bjvm.v6i1.1332 Bangl. J. Vet. Med. (2008). 6 (1): 13-18

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The frequency of resistance to antibiotics of most frequently isolated bacteria from blood cultures during the period 1997-2002

Vojnosanitetski pregled ◽

10.2298/vsp0404391m ◽

2004 ◽

Vol 61 (4) ◽

pp. 391-397

Author(s):

Veljko Mirovic ◽

Branka Tomanovic ◽

Sonja Konstantinovic

Keyword(s):

Clinical Laboratory ◽

Blood Cultures ◽

Diffusion Method ◽

National Committee ◽

Disk Diffusion Method ◽

Beta Lactamases ◽

Resistance To Antibiotics ◽

Extended Spectrum Beta Lactamases ◽

High Level

The aim of this study was to determine the frequency of resistance to antibiotics of the most frequently isolated bacteria from blood cultures of hospitalized patients during the period 1997-2002. The resistance to antibiotics was determined by disk diffusion method according to National Committee for Clinical Laboratory Standards procedures. The majority of staphylococci isolates were resistant to methicillin, and the proportion of methicillin-resistant Staphylococcus aureus was stable (76.8-81.6%), during the follow-up period. None of the staphylococci isolates were resistant to vancomycin, but there was a very high incidence of high-level resistance of enterococci to aminoglycosides (47.2-72.2%). In 1998, only one strain among enterococci was resistant to vancomycin (Enterococcus faecium, VanA fenotype). Enterococcus spp isolates expressed variable frequency of resistance to ampicillin (15-40.1%) during the follow-up period. Among Enterobacteriaceae there were no isolates resistant to imipenem, but dramatic increase of the resistance to ceftriaxone was found from 35.9% in 1997 to 95.9% in 2002 (p<0.001). Extended spectrum beta-lactamases production was found in all the species of enterobacteria isolates. Resistance to imipenem was observed in Acinetobacter spp isolates in 2002 for the first time. Pseudomonas spp isolates expressed high and very variable resistance to all antibiotics tested during the follow-up period.

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Characterization of Plasmid-Mediated Quinolone Resistance and Serogroup Distributions of Uropathogenic Escherichia coli among Iranian Kidney Transplant Patients

BioMed Research International ◽

10.1155/2020/2850183 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Amin Sadeghi ◽

Mehrdad Halaji ◽

Amirhossein Fayyazi ◽

Seyed Asghar Havaei

Keyword(s):

Escherichia Coli ◽

Nalidixic Acid ◽

Kidney Transplant ◽

Uropathogenic Escherichia Coli ◽

Quinolone Resistance ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Transplant Patients ◽

Kidney Transplant Patients ◽

Plasmid Genes

Introduction. Urinary tract infection (UTI) is one of the most frequent infections in kidney transplant patients (KTPs). This infection is mainly caused by uropathogenic Escherichia coli (UPEC). Plasmid-mediated quinolone resistance (PMQR) was also increasingly identified in UPEC. This study proposed to investigate the frequency of quinolone-resistance plasmid genes and the O-antigen serogroup among UPEC isolated from KTPs and non-KTP with UTI. Methods. Totally, 114 UPEC isolates from 49 KTPs and 65 non-KTPs patients diagnosed with an UPEC-associated UTI were obtained from June 2019 to December 2019 at three laboratory centers in Isfahan, Iran. The isolates were confirmed through phenotypic and genotypic methods. Moreover, the antimicrobial susceptibility test to nalidixic acid, ciprofloxacin, norfloxacin, and ofloxacin was performed using a disk diffusion method. The presence of the qnr gene as well as the serogroup distribution was identified using the PCR method. Result. According to data, the distribution of O1, O2, O4, O16, and O25 serogroups were 3.5%, 2.6, 3.5, 3.5, and 20.2%, respectively. Antibiotic susceptibility pattern revealed that the highest and lowest resistance rates were to nalidixic acid (69.3%) and norfloxacin (43.9%), respectively. Also, the frequency of qnrS and qnrB genes were 33.3% and 15.8%, respectively, while none of the isolates was found to be positive for the qnrA gene. There was no significant association between the presence of qnr genes and higher antibiotic resistance. Conclusion. This study recognized that the qnrS gene, O25 serotype, and resistance to nalidixic acid had the highest frequencies in UPEC strains isolated from UTI patients.

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Fluconazole Susceptibilities of Bloodstream Candidasp. Isolates as Determined by National Committee for Clinical Laboratory Standards Method M27-A and Two Other Methods

Journal of Clinical Microbiology ◽

10.1128/jcm.37.7.2197-2200.1999 ◽

1999 ◽

Vol 37 (7) ◽

pp. 2197-2200 ◽

Cited By ~ 12

Author(s):

Emilia Cantón ◽

Javier Pemán ◽

Alfonso Carrillo-Muñoz ◽

Ana Orero ◽

Pedro Ubeda ◽

...

Keyword(s):

Clinical Laboratory ◽

Geometric Mean ◽

Inhibition Zone ◽

Diffusion Method ◽

National Committee ◽

Dilution Method ◽

Inhibition Zone Diameter ◽

Zone Diameter ◽

The Mean

The in vitro activity of fluconazole against 143Candida spp. obtained from the bloodstreams of 143 hospitalized patients from 1995 to 1997 was studied. Susceptibility tests were carried out by two macrodilution methods, the M27-A and a modified M27-A method (0.165 M, pH 7/morpholinepropanesulfonic acid-buffered RPMI 1640 medium supplemented with 20 g ofd-dextrose per liter), and by the agar diffusion method (with 15-μg fluconazole [Neo-Sensitab] tablets). With 2 μg of fluconazole per ml, 96.92% of 65 C. albicans isolates, 86.2% of 58 C. parapsilosis isolates 7 of 8 C. tropicalis isolates, and 1 of 6 C. glabrata isolates were inhibited. Only one strain of C. albicans and one strain of C. tropicalis were resistant. The agreement between the two macrodilution methods was greater than 90% within ±2 log2 dilutions for all strains except C. glabrata (83.3%) and C. tropicalis(87.5%). Generally, MICs were 1 log2 dilution lower in glucose-supplemented RPMI 1640 medium. No correlation between zone sizes and MICs was found. All strains susceptible by the diffusion test were susceptible by the dilution method, but the converse was not necessarily true. Interestingly, inhibition zones were smaller forC. albicans, for which the geometric mean MIC was 0.29 μg/ml and the mean inhibition zone diameter was 25.7 mm, while for C. parapsilosis the geometric mean MIC was 0.96 μg/ml and the mean inhibition zone diameter was 31.52 mm. In conclusion, the two macrodilution methods give similar results. The modified M27-A method with 2% dextrose has the advantage of shortening the incubation time and simplifying the endpoint determination.

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Department of Microbiology, Bangladesh Agricultural University, Mymensingh

Bangladesh Journal of Medical Microbiology ◽

10.3329/bjmm.v2i2.28839 ◽

2016 ◽

Vol 2 (2) ◽

pp. 3-6

Author(s):

Nahida Akther Zahan ◽

Md. Akram Hossain ◽

AKM Shamsuzzaman ◽

AKM Musa ◽

Md. Chand Mahamud ◽

...

Keyword(s):

Clinical Laboratory ◽

Methicillin Resistance ◽

Meca Gene ◽

Toxin Production ◽

Latex Agglutination ◽

Diffusion Method ◽

National Committee ◽

Dilution Method ◽

Agar Dilution Method ◽

Disk Diffusion Method

The study was done to detect different exotoxins among the strains of Staphylococcus aureus isolated in the department of Microbiology, Mymensingh Medical College in collaboration with the Department of Medicine under the Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh between the periods from July, 2006 to June, 2007. A total of 40 S. aureus isolates investigated in this study were identified by standard microbiological techniques. Antimicrobial susceptibility of the isolates to Oxacillin was carried out by disk diffusion method as per recommendation of the National Committee for Clinical Laboratory Standards. Any isolate showing resistance to Oxacillin was tested again by agar dilution method to determine minimum inhibitory concentration (MIC) of Methicillin. All strains were also tested for mecA gene by Polymerase Chain Reaction (PCR) for confirmation of Methicillin resistance. Enterotoxin (A-D) and Toxic Shock Syndrome Toxin-1 (TSST-1) were detected by Reverse Passive Latex Agglutination (RPLA) test. Out of 40 S. aureus isolates, 7 (17.5%) Methicillin Resistant S. aureus (MRSA), 1 (2.5%) Methicillin Sensitive S. aureus (MSSA) produced Staphylococcal Enterotoxin A (SE-A) and 1 MRSA isolate was positive for TSST-1. In case of combined toxin production among the S. aureus isolates, 2 (5%) MSSA were found to produce SE-A and SE-B, 2 (5%) MSSA produced SE-C and SE-D, and 1 (2.5%) MRSA, 1 (2.5%) MSSA produced SE-C and TSST-1.Bangladesh J Med Microbiol 2008; 02 (02): 3-6

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Use of an Oxacillin Disk Screening Test for Detection of Penicillin- and Ceftriaxone-Resistant Pneumococci

Journal of Clinical Microbiology ◽

10.1128/jcm.37.4.1178-1181.1999 ◽

1999 ◽

Vol 37 (4) ◽

pp. 1178-1181 ◽

Cited By ~ 5

Author(s):

Louise P. Jetté ◽

Christian Sinave

Keyword(s):

Antimicrobial Agents ◽

Clinical Laboratory ◽

Disk Diffusion ◽

Diffusion Method ◽

National Committee ◽

Zone Of Inhibition ◽

Diffusion Test ◽

Disk Diffusion Method ◽

Disk Diffusion Test ◽

Intermediate Resistance

In a context of worldwide emergence of resistance amongStreptococcus pneumoniae strains, early detection of strains with decreased susceptibility to β-lactam antibiotics is important for clinicians. If the 1-μg oxacillin disk diffusion test is used as described by the National Committee for Clinical Laboratory Standards, no interpretation is available for strains showing zone sizes of ≤19 mm, and there is presently no disk diffusion test available for screening cephalosporin resistance. The zones obtained by the diffusion method by using the 1-μg oxacillin disk were compared with penicillin MICs for 1,116 clinical strains and with ceftriaxone MICs for 695 of these strains. Among the 342 strains with growth up to the 1-μg oxacillin disk margin, none were susceptible (MIC, ≤0.06 μg/ml), 62 had intermediate resistance (MIC, 0.12 to 1.0 μg/ml), and 280 were resistant (MIC, ≥2.0 μg/ml) to penicillin. For ceftriaxone, among 98 strains with no zone of inhibition in response to oxacillin, 68 had intermediate resistance (MIC, 1.0 μg/ml), and 22 were resistant (MIC, ≥2.0 μg/ml). To optimize the use of the disk diffusion method, we propose that the absence of a zone of inhibition around the 1-μg oxacillin disk be regarded as an indicator of nonsusceptibility to penicillin and ceftriaxone and recommend that such strains be reported as nonsusceptible to these antimicrobial agents, pending the results of a MIC quantitation method.

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Fluoroquinolone Resistance in Clinical Isolates of Klebsiella Pneumoniae

Journal of Laboratory Physicians ◽

10.1055/s-0040-1716478 ◽

2020 ◽

Vol 12 (02) ◽

pp. 121-125

Author(s):

Pacha Venkataramana Geetha ◽

Kayanam Vijaya Lalitha Aishwarya ◽

Shanthi Mariappan ◽

Uma Sekar

Keyword(s):

Klebsiella Pneumoniae ◽

Clinical Laboratory ◽

Pcr Amplification ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Fluoroquinolone Resistance ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Agar Dilution ◽

High Level

Abstract Introduction Fluoroquinolones are widely used broad-spectrum antibiotics. Recently, increased rate of resistance to this antibiotic has been observed in Klebsiella pneumoniae. The aim of the present study was to determine the presence of quinolone resistance determining regions (QRDR) mutation genes and plasmid-mediated quinolone resistance (PMQR) determinants in clinical isolates of ciprofloxacin-resistant K. pneumoniae. Material and Methods The study included 110 nonduplicate ciprofloxacin-resistant K. pneumoniae clinical isolates. Antibiotic susceptibility testing by disk diffusion method and minimum inhibitory concentration (MIC) by agar dilution methods for ciprofloxacin was performed according to the recommendations of Clinical Laboratory Standards Institute. The presence of QRDR genes and PMQR genes was screened by polymerase chain reaction (PCR) amplification. Result All 110 isolates were resistance to ciprofloxacin, levofloxacin, and ofloxacin. As much as 88% of the isolates exhibited high-level of MIC to ciprofloxacin. Among the 110 isolates, 94(85%) harbored gyrA and 85 (77%) gyrB. The parC and parE genes were detected in 88 (80%) and 64 (58%) isolates. qnrB was detected in 13 (12%) isolates and qnrS in 5 (4.5%) isolates. Two (1.8%) isolates carried both qnrB and qnrS genes. The acc (6')-Ib-cr gene was found in 98 (89%) isolates and oqxAB was detected in 7 (6.3%) isolates. One (0.9%) isolate carried qnrB, acc(6')-Ib-cr and oqxAB genes. Conclusion The prevalence of acc (6')-Ib-cr gene is high among PMQR determinants, followed by qnrB, oqxAB and qnrS.

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