EN ISO 20776-1:2006

Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents 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 (ISO 20776-1:2006)

ISO 20776-1:2006 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 resistance 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 ISO 20776-1:2006, 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 diagnostic test devices) with this reference method for validation, in order to ensure comparable and reliable results.

Labormedizinische Untersuchungen und In-vitro-Diagnostika-Systeme - Empfindlichkeitsprüfung von Infektionserregern und Evaluation von Geräten zur antimikrobiellen Empfindlichkeitsprüfung - Teil 1: Referenzmethode zur Testung der In-vitro-Aktivität von antimikrobiellen Substanzen gegen schnell wachsende aerobe Bakterien, die Infektionskrankheiten verursachen (ISO 20776-1:2006)

Dieser Teil der ISO 20776 beschreibt eine Referenzmethode (Mikrodilution) zur MHK-Bestimmung. Die MHK ist ein Maß für die Aktivität einer Substanz unter den beschriebenen Testbedingungen. Bei der Interpretation für klinische Zwecke können auch andere Faktoren wie die Pharmakologie des Wirkstoffs oder bakterielle Resistenzmechanismen berücksichtigt werden. Diese Vorgehensweise erlaubt die Einstufung bakterieller Isolate in die Kategorien sensibel (S), intermediär (I) und resistent (R). Die Verteilung der MHK-Werte kann zudem dazu dienen, bakterielle Wildtyp-Populationen von Nicht-Wildtyp-Populationen zu unterscheiden. Für bestimmte Antibiotika/Erreger-Kombinationen sind Modifikationen der Basismethode erforderlich, um die klinische Interpretation der MHK-Ergebnisse zu erleichtern. Obwohl die klinische Interpretation nicht zur Zielsetzung dieses Teils der EN ISO 20776 gehört, sind entsprechende Modifikationen in einer separaten Tabelle aufgelistet. Es ist ratsam, andere Methoden zur Empfindlichkeitsprüfung (z. B. mittels Routinetests oder Diagnosegeräten) anhand der Ergebnisse dieser Referenzmethode zu kalibrieren, um vergleichbare und reproduzierbare Werte sicherzustellen.

Systèmes d'essais en laboratoire et de diagnostic in vitro - Sensibilité in vitro des agents infectieux et évaluation des performances des dispositifs pour antibiogrammes - Partie 1: Méthode de référence pour la détermination de la sensibilité in vitro aux agents microbiens des bactéries aérobies à croissance rapide impliquées dans les maladies infectieuses (ISO 20776-1:2006)

L'ISO 20776-1:2006 décrit une méthode de référence, la microdilution en bouillon, pour déterminer les CMI. La CMI reflète l'activité du médicament dans les conditions d'essai décrites, et peut être interprétée pour des besoins de gestion clinique en tenant compte d'autres facteurs tels que la pharmacologie du médicament ou les mécanismes de résistance bactérienne. Cela permet de classer les bactéries comme étant «sensibles» (S), «intermédiaires» (I), ou «résistantes» (R). En outre, les distributions de CMI peuvent être utilisées pour définir les populations bactériennes de type sauvage ou non sauvage. Bien que l'interprétation clinique de la valeur de la CMI se trouve au-delà du domaine d'application de la présente partie de l'ISO 20776, des modifications de la méthode de base sont nécessaires pour certaines combinaisons agent-bactérie afin de faciliter l'interprétation clinique. Ces modifications sont incluses dans un tableau séparé. Il est préférable de comparer les autres méthodes d'essai de réceptivité (par exemple les méthodes de routine ou les dispositifs d'essais de diagnostic) à cette méthode de référence à des fins de validation et pour garantir des résultats comparables et fiables.

Klinični laboratorijski preskusi ter dignostični preskusni sistemi in vitro - Preskus občutljivosti povzročiteljev infekcij na delovanje antimikrobno občutljivih naprav - 1. del: Referenčna metoda za preskus aktivnosti in vitro antimikrobnih povzročiteljev na vpliv bakterij pri nalezljivih boleznih (ISO 20776-1:2006)

General Information

• Status: Withdrawn
• Publication Date: 14-Nov-2006
• Withdrawal Date: 30-Jun-2020
• ICS: 11.100 - Laboratory medicine
• Technical Committee: CEN/TC 140 - In vitro diagnostic systems
• Drafting Committee: CEN/TC 140 - In vitro diagnostic systems
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Completion Date: 01-Jul-2020
• Directive: 98/79/EC - Directive 98/79/EC of the European Parliament and of the Council of 27 October 1998 on in vitro diagnostic medical devices
• Mandate: M/252 - Standardization Mandate to CEN/CENELEC concerning the development of European standards relating to in vitro diagnostic medical devices
• Mandate: M/352 - Supplement n°2 to the CEN's standardisation Mandate concerning methods of analysis for materials and articles intended to come into contact with foodstuffs
• Ref Project: SIST EN ISO 20776-1:2007 - Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents 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 (ISO 20776-1:2006)

Relations

• Replaced By: EN ISO 20776-1:2020 - Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test devices - Part 1: Broth micro-dilution reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases (ISO 20776-1:2019, including Corrected version 2019-12)
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2007
.OLQLþQLODERUDWRULMVNLSUHVNXVLWHUGLJQRVWLþQLSUHVNXVQLVLVWHPLLQYLWUR3UHVNXV
REþXWOMLYRVWLSRY]URþLWHOMHYLQIHNFLMQDGHORYDQMHDQWLPLNUREQRREþXWOMLYLKQDSUDY
GHO5HIHUHQþQDPHWRGD]DSUHVNXVDNWLYQRVWLLQYLWURDQWLPLNUREQLK
SRY]URþLWHOMHYQDYSOLYEDNWHULMSULQDOH]OMLYLKEROH]QLK,62
Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of
infectious agents 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 (ISO 20776-
1:2006)
Labormedizinische Untersuchungen und In-vitro-Diagnostika-Systeme -
Empfindlichkeitsprüfung von Infektionserregern und Evaluation von Geräten zur
antimikrobiellen Empfindlichkeitsprüfung - Teil 1: Referenzmethode zur Testung der In-
vitro-Aktivität von antimikrobiellen Substanzen gegen schnell wachsende aerobe
Bakterien, die Infektionskrankheiten verursachen (ISO 20776-1:2006)
Systemes d'essais en laboratoire et de diagnostic in vitro - Essais de réceptivité d'agents
infectieux et évaluation des performances des dispositifs de réceptivité antimicrobienne -
Partie 1: Méthode de référence pour la détermination de la sensibilité in vitro aux agents
microbiens des bactéries aérobies a croissance rapide impliquées dans les maladies
infectieuses (ISO 20776-1:2006)
Ta slovenski standard je istoveten z: EN ISO 20776-1:2006
ICS:
11.100.10 'LDJQRVWLþQLSUHVNXVQL In vitro diagnostic test
VLVWHPLLQYLWUR systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 20776-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2006
ICS 11.100
English Version
Clinical laboratory testing and in vitro diagnostic test systems -
Susceptibility testing of infectious agents 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 (ISO 20776-1:2006)
Systèmes d'essais en laboratoire et de diagnostic in vitro - Labormedizinische Untersuchungen und In-vitro-
Essais de réceptivité d'agents infectieux et évaluation des Diagnostika-Systeme - Empfindlichkeitsprüfung von
performances des dispositifs de réceptivité antimicrobienne Infektionserregern und Evaluation von Geräten zur
- Partie 1: Méthode de référence pour la détermination de antimikrobiellen Empfindlichkeitsprüfung - Teil 1:
la sensibilité in vitro aux agents microbiens des bactéries Referenzmethoden zur Testing der In-vitro-Aktivität von
aérobies à croissance rapide impliquées dans les maladies antimikrobiellen Substanzen gengen Bakterien, die
infectieuses (ISO 20776-1:2006) Infektionskrankheiten 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 Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national 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.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20776-1:2006: E
worldwide for CEN national Members.

Foreword
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 European 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 the 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 standards 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, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

ANNEX ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 98/79

This European Standard has been prepared under a mandate given to CEN by the European
Commission and the European Free Trade Association to provide one means of conforming to
Essential Requirements of the New Approach Directive 98/79.

Once this standard is cited in the Official Journal of the European Communities under that Directive
and has been implemented as a national standard in at least one Member State, compliance with
the normative clauses of this standard confers, within the limits of the scope of this standard, a
presumption of conformity with the relevant Essential Requirements of that Directive and
associated EFTA regulations.
WARNING: Other requirements and other EU Directives may be applicable to the products
falling within the scope of this standard.

INTERNATIONAL ISO
STANDARD 20776-1
First edition
2006-11-15
Clinical laboratory testing and in vitro
diagnostic test systems — Susceptibility
testing of infectious agents 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
Systèmes d'essais en laboratoire et de diagnostic in vitro — Essais de
réceptivité d'agents infectieux et évaluation des performances des
dispositifs de réceptivité antimicrobienne —
Partie 1: Méthode de référence pour la détermination de la sensibilité in
vitro aux agents microbiens des bactéries aérobies à croissance rapide
impliquées dans les maladies infectieuses

Reference number
ISO 20776-1:2006(E)
©
ISO 2006
ISO 20776-1:2006(E)
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ii © ISO 2006 – All rights reserved

ISO 20776-1:2006(E)
Contents 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 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

ISO 20776-1:2006(E)
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 subject 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 (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 committees 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 be 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 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 agents 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 susceptibility test devices
iv © ISO 2006 – All rights reserved

ISO 20776-1:2006(E)
Introduction
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 important 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. 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
...