1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58systems Susceptibility testing of infectious agents and evaluation of performance of antimicrobial
2、susceptibility test devices Part 1: Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseasesThe European Standard EN ISO 20776-1:2006 has the status of a British StandardICS 11.100Clinical laboratory testing a
3、nd in vitro diagnostic test BRITISH STANDARDBS EN ISO 20776-1:2006BS EN ISO 20776-1:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 December 2006 BSI 2006ISBN 0 580 49791 7Amendments issued since publicationAmd. No. Date Commentscontra
4、ct. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of EN ISO 20776-1:2006.The UK participation in its preparation was entrusted
5、 to Technical Committee CH/212, IVDs.A list of organizations represented on CH/212 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 20776-1November 2006ICS 11.100English Ve
6、rsionClinical laboratory testing and in vitro diagnostic test systems -Susceptibility testing of infectious agents and evaluation ofperformance of antimicrobial susceptibility test devices - Part 1:Reference method for testing the in vitro activity of antimicrobialagents against rapidly growing aero
7、bic bacteria involved ininfectious diseases (ISO 20776-1:2006)Systmes dessais en laboratoire et de diagnostic in vitro -Essais de rceptivit dagents infectieux et valuation desperformances des dispositifs de rceptivit antimicrobienne- Partie 1: Mthode de rfrence pour la dtermination dela sensibilit i
8、n vitro aux agents microbiens des bactriesarobies croissance rapide impliques dans les maladiesinfectieuses (ISO 20776-1:2006)Labormedizinische Untersuchungen und In-vitro-Diagnostika-Systeme - Empfindlichkeitsprfung vonInfektionserregern und Evaluation von Gerten zurantimikrobiellen Empfindlichkeit
9、sprfung - Teil 1:Referenzmethoden zur Testing der In-vitro-Aktivitt vonantimikrobiellen Substanzen gengen Bakterien, dieInfektionskrankheiten verursachen (ISO 20776-1:2006)This European Standard was approved by CEN on 14 November 2006.CEN members are bound to comply with the CEN/CENELEC Internal Reg
10、ulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This Eur
11、opean Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the nation
12、al standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom
13、.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 20776-1:2006: EForewor
14、d This document (EN ISO 20776-1:2006) has been prepared by Technical Committee CEN/TC 140 “In vitro diagnostic medical devices“, the secretariat of which is held by DIN, in collaboration with Technical Committee ISO/TC 212 “Clinical laboratory testing and in vitro diagnostic test systems“. This Euro
15、pean Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2007, and conflicting national standards shall be withdrawn at the latest by May 2007. This document has been prepared under a mandate given to CEN by th
16、e European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this document. According to the CEN/CENELEC Internal Regulations, the national standard
17、s organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Roman
18、ia, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN ISO 20776-1:2006Reference numberISO 20776-1:2006(E)INTERNATIONAL STANDARD ISO20776-1First edition2006-11-15Clinical laboratory testing and in vitro diagnostic test systems Susceptibility testing of infectious agents and evalua
19、tion of performance of antimicrobial susceptibility test devices Part 1: Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases Systmes dessais en laboratoire et de diagnostic in vitro Essais de rceptivit da
20、gents infectieux et valuation des performances des dispositifs de rceptivit antimicrobienne Partie 1: Mthode de rfrence pour la dtermination de la sensibilit in vitro aux agents microbiens des bactries arobies croissance rapide impliques dans les maladies infectieuses EN ISO 20776-1:2006ii iiiConten
21、ts Page Foreword iv Introduction v 1 Scope . 1 2 Terms and definitions. 1 3 Test procedures 4 3.1 General. 4 3.2 Medium 4 3.3 Antimicrobial agents 4 3.4 Preparation of inoculum 9 3.5 Inoculation of microdilution trays. 10 3.6 Incubation of microdilution trays 10 3.7 Reading results . 10 3.8 Special
22、test situations where the MIC result might give unreliable results . 10 4 Quality control. 11 Annex A (normative) Requirements for Mueller-Hinton broth. 16 Bibliography . 18 Annex ZA (informative) Relationship between this European Standard and the EssentialRequirements of EU Directive 98/79. 20 EN
23、ISO 20776-1:2006iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a su
24、bject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (
25、IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical commi
26、ttees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not b
27、e held responsible for identifying any or all such patent rights. ISO 20776-1 was prepared by the European Committee for Standardization (CEN) Technical Committee CEN/TC 140, In vitro diagnostic medical devices, in collaboration with Technical Committee ISO/TC 212, Clinical laboratory testing and in
28、 vitro diagnostic test systems, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement). ISO 20776 consists of the following parts, under the general title Clinical laboratory testing and in vitro diagnostic test systems Susceptibility testing of infectious a
29、gents and evaluation of performance of antimicrobial susceptibility test devices: Part 1: Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases Part 2: Evaluation of performance of antimicrobial susceptibil
30、ity test devices EN ISO 20776-1:2006vIntroduction In vitro susceptibility tests are performed on microorganisms suspected of causing disease, particularly if the organism is thought to belong to a species that may exhibit resistance to frequently used antimicrobial agents. The tests are also importa
31、nt in resistance surveillance, epidemiological studies of susceptibility and in comparisons of new and existing agents. Dilution procedures are used to determine the minimum inhibitory concentrations (MICs) of antimicrobial agents and are the reference method for antimicrobial susceptibility testing
32、. MIC methods are used in resistance surveillance, comparative testing of new agents, to establish the susceptibility of organisms that give equivocal results in routine tests, for tests on organisms where routine tests may be unreliable and when a quantitative result is required for clinical manage
33、ment. In dilution tests, microorganisms are tested for their ability to produce visible growth on a series of agar plates (agar dilution) or in broth (broth dilution) containing serial dilutions of the antimicrobial agent. The lowest concentration of an antimicrobial agent (in mg/l) that, under defi
34、ned in vitro conditions, prevents the appearance of visible growth of a microorganism within a defined period of time is known as the MIC. The MIC is a guide for the clinician to the susceptibility of the organism to the antimicrobial agent and aids treatment decisions. Careful control and standardi
35、sation is required for intra- and inter-laboratory reproducibility, as results may be significantly influenced by the method used. It is generally accepted that broth MIC tests are reproducible to within one doubling dilution of the real end point (i.e. one well or tube in a doubling dilution series
36、). Broth dilution is a technique in which containers holding identical volumes of broth with antimicrobial agent solutions in incrementally (usually geometrically) increasing concentrations are inoculated with a known number of microorganisms. Broth microdilution denotes the performance of the broth
37、 dilution test in microdilution trays. The method described in this part of ISO 20776 is intended for the testing of pure cultures of aerobic bacteria that are easily grown by overnight incubation on agar and grow well in Mueller-Hinton broth, which may be supplemented. The broth microdilution metho
38、d described in this part of ISO 20776 is essentially the same as those used in many countries, including France1, Germany2, Sweden3, the United Kingdom4, and the United States5. The method is also essentially the same as the broth microdilution method published by the European Committee on Antimicro
39、bial Susceptibility Testing (EUCAST)6. All these methods are based on those described by Ericsson and Sherris7. EN ISO 20776-1:2006blank1Clinical laboratory testing and in vitro diagnostic test systems Susceptibility testing of infectious agents and evaluation of performance of antimicrobial suscept
40、ibility test devices Part 1: Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases WARNING The use of this part of ISO 20776 may involve hazardous materials, operations and equipment. This part of ISO 20776
41、 does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this part of ISO 20776 to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1 Scope This part of ISO 20776
42、describes one reference method, broth microdilution, for determination of MICs. The MIC reflects the activity of the drug under the described test conditions, and can be interpreted for clinical management purposes by taking into account other factors, such as drug pharmacology or bacterial resistan
43、ce mechanisms. This allows categorization of bacteria as “susceptible” (S), “intermediate” (I), or “resistant” (R). In addition, MIC distributions can be used to define wild type or non-wild type bacterial populations. Although clinical interpretation of the MIC value is beyond the scope of this par
44、t of ISO 20776, modifications of the basic method are required for certain antimicrobial agent - bacteria combinations to facilitate clinical interpretation. These modifications are included in a separate table. It is advisable to compare other susceptibility testing methods (e.g. routine methods or
45、 diagnostic test devices) with this reference method for validation, in order to ensure comparable and reliable results. 2 Terms and definitions For the purposes of this document, the following terms and definitions apply. 2.1 antimicrobial agent substance of biological, semi-synthetic or synthetic
46、origin that inhibits the growth of or kills bacteria, and is thus of potential use in the treatment of infections NOTE Disinfectants, antiseptics and preservatives are not included in this definition. 2.2 Antimicrobial agents properties 2.2.1 potency antimicrobially active fraction of a test substan
47、ce, determined in a bioassay against a reference powder of the same substance EN ISO 20776-1:20062 NOTE The potency is expressed as mass fraction in milligrams per gram (mg/g), or as activity content in International Units (IU) per gram, or as a volume fraction or mass fraction in percent, or as an
48、amount-of-substance concentration (mass fraction) in mole per litre of ingredients in the test substance. 2.2.2 concentration amount of an antimicrobial agent in a defined volume of liquid NOTE 1 The concentration is expressed as mg/l. NOTE 2 mg/l g/ml but it is not recommended to use the unit g/ml.
49、 2.3 stock solution initial solution used for further dilutions 2.4 minimum inhibitory concentration MIC lowest concentration that, under defined in vitro conditions, prevents visible growth of bacteria within a defined period of time NOTE The MIC is expressed in mg/l. 2.5 breakpoint BP specific values of parameters, such as MICs, on the basis of which bacteria can be assigned to the clinical categories “susceptible”, “intermediate” and “resistant” NOTE For curre
