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Licensed Unlicensed Requires Authentication Published by De Gruyter October 9, 2017

Laboratory performance of sweat conductivity for the screening of cystic fibrosis

  • Ronda F. Greaves EMAIL logo , Lisa Jolly , John Massie , Sue Scott , Veronica C. Wiley , Michael P. Metz , Richard J. Mackay and on behalf of the Australasian Association of Clinical Biochemists Sweat Test Working Party in association with the Royal Australasian College of Pathologists Quality Assurance Programs

Abstract

Background:

There are several complementary English-language guidelines for the performance of the sweat chloride test. These guidelines also incorporate information for the collection of conductivity samples. However, recommendations for the measurement and reporting of sweat conductivity are less clear than for sweat chloride. The aim of the study was to develop an understanding of the testing and reporting practices of sweat conductivity in Australasian laboratories.

Methods:

A survey specifically directed at conductivity testing was sent to the 12 laboratories registered with the Royal College of Pathologists of Australasia Quality Assurance Programs.

Results:

Nine (75%) laboratories participated in the survey, seven of whom used Wescor Macroduct® for collecting sweat and the Wescor SWEAT·CHEK™ for conductivity testing, and the remaining two used the Wescor Nanoduct®. There was considerable variation in frequency and staffing for this test. Likewise, criteria about which patients it was inappropriate to test, definitions of adequate collection sweat rate, cutoffs and actions recommended on the basis of the result showed variations between laboratories.

Conclusions:

Variations in sweat conductivity testing and reporting reflect many of the same issues that were revealed in sweat chloride test audits and have the potential to lead to uncertainty about the result and the proper action in response to the result. We recommend that sweat testing guidelines should include clearer statements about the use of sweat conductivity.


Corresponding author: Dr. Ronda F. Greaves, School of Health and Biomedical Sciences, RMIT University, PO Box 71, Bundoora, Victoria 3083, Australia

Acknowledgments

We wish to thank Mr Peter Graham and Ms Samantha Shepherd for their assistance in reviewing the data in this manuscript.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: None declared.

  3. Employment or leadership: None declared.

  4. Honorarium: None declared.

  5. Competing interests: The funding organisation(s) played no role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

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Received: 2017-6-16
Accepted: 2017-8-27
Published Online: 2017-10-9
Published in Print: 2018-3-28

©2018 Walter de Gruyter GmbH, Berlin/Boston

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