EQAnews 2000 turns to 2001

In connection with the 3^rd Workshop in Proficency Testing in Analytical Chemistry, Microbiology and Laboratory Medicine, Borås, Sweden 24-27 September 2000 two meetings regarding EQAnews were held.

The first meeting was between the Editor and co-editors, collectively referred to as the Editorial Board. After an introduction of the attendees an agenda consisting of organisational, editorial and practical matters was worked through. In summary it was decided to propose the preparation of a Quality Manual for the production and development of EQAnews. The Quality Manual should consist of sections concerning Definitions, Policies, Standard procedures and Lists. Definitions should assure correct use of terms and phrases. Policies should ease the decision making and make it possible to distribute responsibilities for the production of EQAnews among the members of the Editorial Board. Standard procedures should describe the production process of EQAnews to make it uniform over time and space, meaning that the journal could ideally be made by anyone of the Editorial Board without changes in appearance, lay-out, content etc. Lists should assure that all parties related to EQAnews are registrered e.g. subscribers, advertisers, organisations, admini-strators, tehnical staff.

The responsibility for and the necessary work in the preparation of such a Quality Manual should be shared by all members of the Editorial Board and co-ordinated by the Editor. All entries for the Quality Manual should be approved by the Chair or the Board of EQALM. The Quality Manual could possibly be placed on the EQALM web page, full or partially open to others.

In the second meeting the Editorial Board was allowed to present its proposals to the Board of EQALM and other interested visitors. This led to a good discussion with many new ideas, among them a new column for Letters to the Editor, which starts in this issue, so please send in more letters.

The preparation of a Quality Manual was approved by the Board of EQALM. The Editor of EQAnews will therefore, as soon as possible, begin structuring the work of preparing a Quality Manual. Further details will follow later on or possibly be a good reason for meeting again in connection with the EQALM meeting at the European Congress of Clinical Chemistry and Laboratory Medicine, Prague, 26 – 31 May 2001.

 

A few organisational changes in the relationships between EQAnews, the  former  Supervisors  and  the Board of EQALM were also confirmed. The ownership of EQAnews is now fully transferred to EQALM. This is why EQAnews no longer needs supervisors since the responsibility of issuing the journal is with the Board of EQALM.

It was further decided that advertises in EQAnews could be printed in colour as long as the advertiser pays the regular fee  and covers any extra expenses for the printing process.

 

This issue ends the year 2000 and also the volume 11 of EQAnews. I will therefore use this opportunity to wish all of the readers, the advertisers, the administrative and technical staff and the Editorial Board  of EQAnews together with the members and the Board of EQALM a merry Christmas and a happy New Year, in the hope of a new and fruitful year for EQA, EQALM and EQAnews in 2001.

ERRATUM

Previous no. 3, p. 160: THE KATAL APPROVED FOR CATALYTIC ACTIVITY by René Dybkaer, 1^st column, 1.2.

For “1  mol/min” read “1 mmol/min”,

as correctly shown in the 2^nd column, 1.8.

EQAnews appologises for the mistake.

STANDARDISATION OF FIBRINOLYSIS METHODS

C. Kluft, Gaubius Laboratory, TNO-PG, P.O. Box 2215, NL-2301 CE Leiden, The Netherlands and Department of Thrombosis Research, University of Southern Denmark, Esbjerg, Denmark, e-mail: c.kluft@pg.tno.nl

J. Gram, J. Jespersen, Department of Thrombosis Research, University of Southern Denmark, Esbjerg, Denmark

 

The lysis of thrombi by fibrinolysis is accomplished by proteolytic degradation of fibrin by plasmin which is formed from its precursor plasminogen by the enzymatic action of plasminogen activators, such as tissue-type Plasminogen Activator (t-PA). Both stages can be inhibited: plasmin by Plasmin Inhibitor, (previously a2-Antiplasmin), and t-PA by Plasminogen Activator Inhibitor-1 (PAI-1).

 

Following the insight into the biochemistry of fibrinolysis, laboratory diagnostic procedures have evolved from global biological methods such as clot lysis and fibrin plate methods into specific enzymatic methods with chromogenic peptide substrates and into enzyme immunoassays frequently employing specific monoclonal antibodies. However, neither has the analytical reliability of fibrinolysis methods has kept up with technical advances, nor was a general standardisation policy developed beyond a system of available standards (1-3).

Historically, the procedures were developed in specialist laboratories as research methods. More recently many commercial procedures have become available with different methods for each analyte. Since it has become clear that there is a large laboratory-to-laboratory variation in the results reported for a given analyte, efforts to improve the standardisation of methods are necessary.

 

Attempts have been made to standardise fibrinolysis methods within the frame-work of the Scientific and Standardisation Committee (SSC) of the International Society on Thrombosis and Haemostasis (ISTH). Significant problems have been identified and suggestions for improvement have been defined by the experts of SSC for a number of fibrinolytic analytes. Two initial surveys disclosed significant problems with plasminogen activator inhibitor 1 (PAI-1) antigen (imm. proced.) and PAI-1 (enzymatic procedure) (4,5). Sufficient harmonisation of results could not be obtained solely with the use of a common standard. A second evaluation with engineered samples to test the specificity of the enzymatic methods, after the experts of the SSC/ISTH had defined criteria for specificity, showed that most methods did not fulfil all specificity criteria, explaining partly the large variation produced by different methods (6). For PAI-1 (immumoassay procedure) the problem was further illustrated from a study using five commercial assays and the replacement of kit calibrators by one common calibrator from NIBSC. Results nevertheless showed a five-fold range of deviation between results. Similar results were obtained with a corresponding study for t-PA (immunoassay procedure), where in addition the SSC secondary plasma standard was spiked with a range of purified t-PA, suggesting specificity problems, which were not exclusively related to matrix effects (7).

 

In studies of patients congenitally deficient in Plasmin Inhibitor significant problems were encountered when measuring homozygous deficiency. The failure to detect values close to zero de-monstrates that most methods had specificity problems (8,9). Thus a proper diagnosis of homozygote and heterozygote Plasmin Inhibitor deficiency may be difficult with most analytical methods.

A project group within the Subcommittee of Fibrinolysis of the SSC/ISTH focused on four methods for clinically relevant analytes and analytes important for epidemiology and research. It concerned PAI-1 (enzymatic procedure), t-PA (immunoassay procedure), Plasmin Inhibitor (enzymatic procedure) and plasminogen (enzymatic procedure). Criteria for specificity and procedures for testing were formulated by small working groups and discussed and approved in plenary sessions of the Subcommittee on Fibrinolysis. The results are being published. The testing of specificity was undertaken once within the framework of the SSC/ISTH for PAI-1 activity (6), but further studies were left to developers of methods.

 

In 1997 the SSC/ISTH and IFCC formed a joint Committee on Standardisation of Coagulation Tests (C-SCT) (10). This combined the expertise of the SSC/ISTH and IFCC in creating and implementing reference methods and the further hierarchical structure of standardisation of methods. The aim of the Committee goes beyond fibrinolysis and includes coagulation (11).

References

1. Gram J, Jespersen J, Kluft C, Declerck P. Various  approaches to standardization and the importance of measurement accuracy. Fibrinolysis 1996; 10/ Suppl. 2: 113-6.

 

2. Gram J, Kluft C, Jespersen J. Standardization of measurement of components of the fibrinolytic system - Introduction and Current Status. Electronic J IFCC  2000: http://194.79.144.120/ejifcc/vol 12no2/standcompfibsys.htm.

 

3. Gaffney PJ. Standards in fibrinolysis - current status and future challenges. Thromb Haemost 1995; 74: 1389-97.

 

4. Gram J, Declerck PJ, Sidelmann J, Jespersen J, Kluft C. Multicentre evaluation of commercial kit methods: Plasminogen activator inhibitor activity. Thromb Haemost 1993; 70: 852-7.

 

5. Declerck PJ, Moreau H, Jespersen J, Gram J, Kluft C. Multicentre evaluation of commercially available methods for the immunological determination of plasminogen activator inhibitor-1 (PAI-1). Thromb Haemost 1993; 70: 858-63.

 

6. Kluft C. Criteria and search for specific assays for active plasminogen activator inhibitor 1 (PAI-1) in plasma. Electronic J IFCC, 2000: http://194.79.144.120/ejifcc /vol12no2/PAI-1assays.htm.

 

7. De Maat MPM, Gram J, Jespersen J, Kluft C. A common calibrator does not secure harmonisation of commercial t-PA and PAI-1 antigen measurements. Electronic J IFCC (in press).

 

8. Meijer P, Kluft C. Criteria for an automated specific plasmin inhibitor test (SPIT) in human plasma. Fibrinolysis 1996; 10 (suppl 2): 121-3.

 

9. Billing Clason S, Meijer P, Kluft C, Ersdal E. Specific determination of plasmin inhibitor activity in plasma : documentation of specificity of manual and automated procedures. Blood Coag Fibr. 1999; 10: 487-94.

 

10. www.ifcc.org (see Scient Division 8.4.8).

 

11. Kluft C, Gram J, Jespersen J. Laboratory diagnostic methods for fibrinolysis. Clin Chem Lab Med 1999; 37: S 19 (Abstr.).

BULLETIN OF THE WORLD HEALTH ORGANISATION. THE INTERNATIONAL JOURNAL OF PUBLIC HEALTH

Dr. André Deom, Commission des Laboratoires HUG, Hôspital Cantonal, Rue Micheli-du-Crest 24, 12 11 Genève 14, Switzerland, e-mail: cscq.admin@hcuge.ch

Established for more than 50 years as a leading research journal, the Bulletin of the World Health Organisation commemorates the turn of the century by taking on some of the most challenging public health issues of the day.

 

Each month, Bulletin 2000 features specially commissioned research articles and opinion papers that tackle a selected problem from a diversity of approaches. Invited experts debate the issues further in a related round table discussion. Finally, presentation of a public health classic puts the issues in historical perspective and helps gauge the progress of thought and action.

 

By submitting pressing health problems to expert analysis and debate, Bulletin 2000 aims to show how the best research and thinking can crystallise the issues - and move us closer to solutions that bring the greatest practical gains.

 

The remainder of each journal issue continues its traditional coverage of biomedical and scientific research, supported by contributions form the social and behavioural sciences. In selecting articles for publication, the editors give priority to original findings that advance understanding of health problems - and ways to solve them - in a world where health concerns every country, and diseases respect no boundaries.

 

Themes scheduled for coming issues:

 

·      Inequalities in health

·      Immunisation safety

·      Polio eradication

·      Mental health

·      Reproductive health

·      Health systems

 

LETTER TO THE EDITOR

Proficiency testing for FVL and P20210A in UK NEQAS can identify laboratory errors

 Dear Editor,

 We were interested to read the article by Larsen and Uldall (EQAnews 2000; 11: 164-8), regarding EQA for Factor V Leiden mutation, in which 13 laboratories correctly identified the Factor V Leiden genotype of all nine samples distributed. These findings were in agreement with previously published data from Lutz et al (Clin Chem 1998; 44: 1356-8), who reported 100% concordance between six laboratories, testing 62 samples for the mutation. A UK NEQAS proficiency testing programme was established prior to these publications, in 1997, and now comprises 66 participants in 14 different countries. Five samples are distributed for investigation in each survey, and to date seven surveys have been completed. Participants are invited to perform screening for Factor V Leiden, P20210A mutation, and in two surveys also performed screening for the MTHFR mutation C677T. In six of these seven surveys, errors have occurred, at a rate of 2-7% of participants (table 1).

Errors include reporting of a negative FVL screen for a subject homozygous for the defect, and homozygosity for the P20210A defect in an unaffected donor.

Both transcription and analytical errors have been identified. A wide variety of DNA extraction methods, and commercial sources of primer and restriction enzyme were employed and no one method was associated with a higher rate of error.

 

Hofgartner and Tait (Am J Clin Pathol 1999; 112: 14-21) reported problems in clinical genetic testing in the United States, and our findings confirm that molecular genetic testing for thrombophilia is not 100% reliable. Unlike many haemostatic investigations, identification of the presence or absence of a genetic defect is unlikely to be confirmed by repeat testing. Given the implications for management of the investigated individual and for family studies, our findings confirm that proficiency testing programs are an important component of the quality assurance of molecular genetic testing for thrombophilia.

 

	Error rate (% of laboratories)
Survey No.	FVL	P20210A	MTHFR
1	4.9	-	-
2	2.6	-	-
3	4.5	5.7	-
4	2.3	0.0	7.1
5	0.0	0.0	0.0
6	2.1	4.3	-
7	6.8	3.5	-

Editor of EQAnews is:

Peter K. Mogensen. Novozymes A/S, 6E2.14, Krogshoejvej 36, DK-2880 Bagsvaerd, Denmark. E-mail: pkm@novozymes.com

 

Fieldspecific co-editors are:

Dr. Michael Noble (clinical microbiology). Clinical Microbiology Proficiency Testing, University of British Columbia, Room 328A, Heather Pavilion C, Floor 27, Heather Street, Vancouver, BC V5Z, Canada. E-mail: mnoble@ interchange.ubc.ca

 

Dr. Joergen Kurtzhals (clinical parasitology). Dept. Clin. Microbiol., Statens Serum Institute, Artillerivej 5, DK-2300 Copenhagen S, Denmark. E-mail: jku@ssi.dk

 

Dr. Igor Bondarenko (clinical virology). Russian Research Institut for Metrology, 19 Moskovsky Pr., St. Petersburg, 198005 Russia. E-mail: bigor@mail.lanck.net

 

Dr. Nils Joergensen (clinical biochemistry). Dept. Clin. Biochem. Soenderborg Hospital, DK-6400 Soenderborg, Denmark. E-mail: nils.borg@po.ia.dk

 

Dr. Jan Moeller (clinical biochemistry). Dept. Clin. Biochem. Skejby Sygehus, Aarhus University Hospital, Brendstrupgaardsvej, DK-8200 Aarhus, Denmark. E-mail: jan@kba.sks.au.dk

 

Dr. Vives Corrons (haematology). Haematology Lab. Dept., Escala 1 B – Planta 3, Hospital Clinic 1 Provincial, C/ Villaroel 170, ES-08036 Barcelona, Spain. E-mail: jlvives@medicina.ub.es

 

Dr. Frits Haverkate (coagulation and haemostasis). Gaubius Laboratory TNO. P.O. Box 2215, NL-2301 CE Leiden, The Netherlands. E-mail: f.haverkate@pg. tno.nl

 

Dr. Jonathan Middle (language revision). UK NEQAS, P.O. Box 3909, Birmingham B15 2UE, UK. E-mail: j.g.middle@bham.ac.uk

 

Manuscripts

Manuscripts should be received no later than the first working day of the month prior to the month of issuing EQAnews, preferably in an electronic medium.

 

Editorials

Communications in EQAnews which carry no identification of authorship are written by the Editor.

 

Correspondence to EQAnews

All correspondence to EQAnews should be send to the Editor.

The Editor takes no legal or financial responsibility for errors or misinformation which may occur in EQAnews.

 

© 2000 by EQALM and IFCC.