Categorization of temocillin susceptibility using the disc diffusion method: Susceptible, Intermediate, Resistant or Undetermined?

2020 ◽  
Author(s):  
Amandine HENRY ◽  
Anthony Michaud ◽  
Nicolas Degand ◽  
Emmanuelle Bille ◽  
Damien Fournier ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Inhibition Zone ◽  
Generation Cephalosporin ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Disc Diffusion Method ◽  
Beta Lactamases ◽  
Inhibition Zone Diameter ◽  
Zone Diameter ◽  
Extended Spectrum Beta Lactamases

Abstract Background: Since the pandemic of ESBL (extended-spectrum beta-lactamases) and the emergence of carbapenemase-producing Enterobacterales there is a renewed interest in temocillin. However, as the molecule was little used, except in Belgium and UK, there are few guidelines for its antibiotic susceptibility testing (AST). We aim to assess the accuracy of the disc diffusion method (DDM) for temocillin susceptibility testing. Methods: Eight hundred eighty-eight Enterobacterales clinical strains of which 61.7% were resistant to 3 rd generation cephalosporin (3GC-R) were included. AST was performed using DDM in comparison to gradient strip tests (GST) and interpreted using the diameter breakpoint of 20mm and MIC breakpoint of 8 mg/L for DDM and GST as recommended by EUCAST-CASFM recommandations. Results: At breakpoint of 8mg/L, temocillin rates of susceptibility were 76.9%, 95.6% and 67.7% for overall, 3GC-S and 3GC-R strains respectively. Ninety-four (10.6%) discrepancies were noticed including 68 (72.3%) major errors and 26 (27.6%) very major errors. Sixty-eight (72.3%) of all errors correspond to inhibition diameters comprised between 17 and 23 mm. The presence of colonies within the inhibition diameter was noticed for 32 (5.3%) strains susceptible to temocillin. Conclusions: DDM lacks accuracy for strains displaying borderline inhibition zone diameter. We suggest applying the concept of area of technical uncertainty (ATU) for standard DDM. The strains displaying a diameter within the ATU should be tested by another method. The significance of colonies within the inhibition zone diameter should be explored.

scholarly journals Formulation and Antibacterial Activity of Liquid Soap Containing Ketapang (Terminalia catappa L.) Leaves Extract

2021 ◽  
Vol 4 (1) ◽  
pp. 43-50
Author(s):  
Asiska Permata Dewi ◽  
Dini Mardhiyani
Keyword(s):  
Antibacterial Activity ◽  
Staphylococcus Epidermidis ◽  
Foam Stability ◽  
Inhibition Zone ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Liquid Soap ◽  
Disc Diffusion Method ◽  
Inhibition Zone Diameter ◽  
Terminalia Catappa

Ketapang (Terminalia catappa L.) is traditionally used by the community to treat infections of the skin caused by bacteria or fungi. In this study, T. catappa leaves extract was added to the liquid soap formula as an antibacterial. The purpose of this study was to determine the secondary metabolite compounds contained in T. catappa leaves extract, physical evaluation of the preparation, and antibacterial activity of liquid soap. Liquid soap formula is made with various concentrations of T. catappa leaves extract F0 (0%), F1 (1%), F2 (2%), and F3 (3%). The resulting soap was evaluated for organoleptic, pH, high foam, homogeneity, irritation, and its activity against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli using the disc diffusion method. The results showed that the T. catappa leaves extract contained flavonoids, tannins, saponins, and triterpenoids. The liquid soap formula F0 is clear, while F1, F2, and F3 have the characteristics of brown-dark brown, homogeneous, pH between 4.6-5.2, foam stability between 67-72%, which is not significantly different and stable after five minutes of testing, and it does not irritate the skin. Terminalia catappa leaves extracts liquid soap has antibacterial activity at a concentration of 1%, 2%, and 3%, with the largest inhibition zone diameter produced by S. aureus.

scholarly journals Antifungal and growths regulation activity of new metal-organic compounds

2019 ◽  
Vol 16 (2) ◽  
pp. 143-149
Author(s):  
O. V. Bashta ◽  
L. P. Pasichnyk ◽  
N. M. Voloshchuk ◽  
G. G. Repich ◽  
O. O. Zholob ◽  
...  
Keyword(s):  
Seed Germination ◽  
Organic Compounds ◽  
Copper Complex ◽  
Inhibition Zone ◽  
Diffusion Method ◽  
Chelate Complexes ◽  
Inhibition Zone Diameter ◽  
Zone Diameter ◽  
Grain Crops ◽  
Metal Organic

The aim of present paper is to study the antifungal activity of the new platinum, palladium and copper chelate complexes with different organic ligands against Fusarium strains and to determine the influence of these compounds on the germination energy and seed germination of investigated grain crops. Methods. In vitro antifungal activities of new chelate complexes were studied by the agar disk diffusion method. New complexes were tested against pathogenic Fusarium strains such as — F. culmorum 3260/4, F. verticillioides and F. sporotrichioides. The toxic effect of new complexes was evaluated according to changes in germination power and seed germination of grain crops — winter wheat, vernal barley and maize. The determination of these characteristics was carried out in accordance with the standard demands. Results. Our results revealed that palladium complex H exhibited fungicidal activity against F. culmorum 3260/4 and fungistatic activity against F. verticillioides with growth inhibition zone diameter 25 mm ad 20 mm respectively. Copper complex 2 showed a moderate fungicidal effect against F. culmorum 3260/4 strain (inhibition zone diameter 12 mm). The treatment of grain crops seeds with the H and 2 complexes demonstrated the less toxicity than standard agent — commercial fungicide tebuconazol. These complexes had also less negative influence on the germination power for all test cultures than tebuconazol. Copper complex 2 showed a noticeable growth promoting effect on studied seeds compared to seeds under conditions without treatment. Conclusions. Thus, the studied complexes can be considered as promising antifungal agents with growth regulating properties. The directional modification of the complexes to obtain the more potent derivatives will be performed.Keywords: metal-organic compounds, antifungal, growths regulation activity.

scholarly journals Russia-made Mueller–Hinton agar: compliance with contemporary requirements

2019 ◽  
Vol 9 (2) ◽  
pp. 409-416
Author(s):  
L. V. Domotenko ◽  
I. S. Kosilova ◽  
A. P. Shepelin
Keyword(s):  
Quality Control ◽  
Antimicrobial Agents ◽  
Susceptibility Testing ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Disc Diffusion Method ◽  
Nutrient Media ◽  
Mueller Hinton ◽  
Mueller Hinton Agar

At present, a rise of antimicrobial resistance requires that susceptibility of infectious agents to antimicrobial agents could be accurately evaluated as related errors may lead to selecting improper therapeutics provoking spread of drug resistance. Pathogen sensitivity to antimicrobial agents is commonly determined by a disc diffusion method. A quality of nutrient medium used in assays plays a crucial role influencing final results. In Russia, it turned out that regulatory documents such as the nationwide guidelines and clinical recommendations outlining methodology for antimicrobial susceptibility testing underlay availability in domestic market few nutrient media, including Mueller–Hinton Agar, AGV medium etc. exhibiting sometimes unsatisfactory quality. To harmonize such methodology with international requirements, theStateResearchCenterfor Applied Microbiology and Biotechnology has developed a technology and promoted manufacture of Russia-made Mueller–Hinton agar satisfying requirements of EUCAST documents, clinical guidelines, and ISO/TS 16782:2016. The main objective of this study was to compare quality of new agar product with five similar foreign media while examining 11 test strains by disc diffusion method. As a result, some of nutrient media available to the Russian market turned out to be off-standard: not all of them satisfy to the EUCAST requirements and clinical guidelines since diameter distribution for growth inhibition recommended by EUCAST for quality control does not fit into permissible range. Moreover, susceptibility of P. aeruginosa ATCC 27853 to aminoglycosides, fluoroquinolones, Meropenem, as well as S. aureus ATSS 25923 and E. faecalis ATCC 29212 to tigecycline was assessed with certain mistakes. The data obtained by us were analyzed in accordance to the new document ISO/TS 16782:2016 “Clinical laboratory testing — criterion for acceptable lots of dehydrated Mueller–Hinton agar and broth for antimicrobial susceptibility testing”, not approved yet In Russia. To determine potential reason for deviation of data from reference range, we measured concentration of bivalent metals in all nutrient media examined by atomic emission spectrometry with inductively coupled plasma. We determined new patterns affecting reliability of results on microbial antibiotic susceptibility. A need to check intralaboratory quality control of nutrient media was emphasized.  

Current Fluoroquinolone Susceptibility Criteria for Salmonella Needs Re-evaluation

2012 ◽  
Vol 10 (1) ◽  
pp. 66-71 ◽  
Author(s):  
D Acharya ◽  
S Malla ◽  
DR Bhatta ◽  
N Adhikari ◽  
SP Dumre
Keyword(s):  
Nalidixic Acid ◽  
Enteric Fever ◽  
Susceptibility Testing ◽  
Break Point ◽  
Resistance Rate ◽  
Diffusion Method ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Disc Diffusion ◽  
Zone Diameter

Background Disc diffusion technique is the routine susceptibility testing procedure for isolates of enteric fever, the most common clinical diagnosis among febrile patients in Nepal. Objective To evaluated the current fluoroquinolones (FQs) susceptibility criteria and nalidixic acid screening test in Salmonella enterica serovar Typhi and Paratyphi A. Methods S. Typhi and Paratyphi A strains isolated from 443 suspected enteric fever patients visiting National Public Health Laboratory (NPHL) during April through October 2008 were analyzed. All isolates were confirmed by standard microbiological procedures including serotyping. Antibiotic susceptibility testing was performed by using Kirby Bauer disc diffusion method and Clinical and Laboratory Standards Institute (CLSI) approved interpretive criteria. Agar dilution method was used to determine Minimum Inhibitory Concentration (MIC) of ciprofloxacin, ofloxacin and nalidixic acid. Result Out of 41 Salmonella isolates, 80.49% were nalidixic acid resistant, with S. Paratyphi A showing higher resistance rate (88.23%) compared to S. Typhi (75%). The difference in both MIC and zone diameter in nalidixic acid susceptible and nalidixic acid resistant isolates was found to be significant (P < 0.001) and decreased susceptibility to FQs was strongly correlated (sensitivity and specificity of 100%) with resistance to nalidixic acid. Regression analysis of MIC against zone diameter based on the current CLSI recommended guidelines suggests that accommodation of current susceptible and resistant MIC requires increase in the zone diameter of ciprofloxacin and ofloxacin. Conclusion Before using these drugs for management of enteric fever, appropriate identification of Salmonella isolates with reduced susceptibility to FQs is essential to limit the possible treatment failure and development of highly resistant strains. The current FQs susceptibility break point criteria for Salmonella need re-evaluation. KATHMANDU UNIVERSITY MEDICAL JOURNAL  VOL.10 | NO. 1 | ISSUE 37 | JAN - MAR 2012 | 24-29DOI: http://dx.doi.org/10.3126/kumj.v10i1.6909

scholarly journals Interpretive criteria to differentiate low- and high-level mupirocin resistance in Staphylococcus aureus

2007 ◽  
Vol 56 (7) ◽  
pp. 937-939 ◽  
Author(s):  
Naira Elane Moreira de Oliveira ◽  
Ana Paula Couto Marques Cardozo ◽  
Elizabeth de Andrade Marques ◽  
Kátia Regina Netto dos Santos ◽  
Marcia Giambiagi deMarval
Keyword(s):  
Staphylococcus Aureus ◽  
High Resistance ◽  
The Other ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Disc Diffusion Method ◽  
Zone Diameter ◽  
Resistant Strains ◽  
Mupirocin Resistance ◽  
High Level

Meticillin-resistant Staphylococcus aureus isolates were classified into three mupirocin susceptibility groups by the disc diffusion method using 5 and 200 μg mupirocin discs. The zone diameter observed for a 5 μg disc distinguished MupS from the resistant strains (either MupRL or MupRH). On the other hand, a 200 μg disc distinguished the high-resistance MupRH strains from the other two (MupS or MupRL). Thus, the concomitant use of 5 and 200 μg mupirocin discs allowed the clear distinction among the three mupirocin susceptibility groups, MupS, MupRL or MupRH.

scholarly journals ISOLASI JAMUR SIMBION ASCIDIA Schizophyllum commune YANG MEMILIKI AKTIVITAS ANTIBAKTERI

2021 ◽  
Vol 9 (1) ◽  
pp. 22
Author(s):  
Gianfranco Montolalu ◽  
Deiske A Sumilat ◽  
Natalie D.C. Rumampuk ◽  
Inneke FM Rumengan ◽  
Rosita AJ Lintang ◽  
...  
Keyword(s):  
Biological Activities ◽  
Schizophyllum Commune ◽  
Inhibition Zone ◽  
Benthic Invertebrate ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Disc Diffusion Method ◽  
Self Defense ◽  
Identification Of Fungi ◽  
Symbiotic Fungi

Ascidian is a benthic invertebrate that produces secondary metabolites. The substances were produced by the ascidian as self-defense from many environmental factors. Several studies report the similar structure between the substances extracted from ascidian and symbiotic fungi with biological activities. This study aims to isolate fungi associated with ascidian Eudistoma sp., then observe its potency on inhibiting bacteria S. aureus dan A. hydrophila. PDA was used to isolate and culture fungal isolate, then extraction using solvent ethyl acetate. Antibacterial activity of this symbiotic fungi isolates extract was performed using the Kirby-Bauer disc diffusion method. Molecular identification of fungi results that the symbiotic fungi were Schizophyllum commune. The observing result showed that fungal extract has the ability on inhibiting the growth of S. aureus and with the inhibition zone 8 mm and A. hydrophila 8,5 mm.Keywords: Ascidian, Eudistoma sp., Schizophyllum commune, Symbiotic, Antibacterial

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

1999 ◽  
Vol 37 (7) ◽  
pp. 2197-2200 ◽  
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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