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Comparative Study
. 2019 May;33(3):1272-1277.
doi: 10.1111/jvim.15491. Epub 2019 Apr 13.

Comparison of diagnostic techniques for detection of Giardia duodenalis in dogs and cats

Meriam N Saleh  1   2 , Jack R Heptinstall  3 , Eileen M Johnson  2 , Lora R Ballweber  4 , David S Lindsay  1 , Stephen Werre  1 , Joel F Herbein  3 , Anne M Zajac  1
Affiliations
Comparative Study

Comparison of diagnostic techniques for detection of Giardia duodenalis in dogs and cats

Meriam N Saleh et al. J Vet Intern Med. 2019 May.

Abstract

Background: An evaluation of currently available in-clinic diagnostic tests for Giardia duodenalis infection of dogs and cats has not been performed. In addition, there is discordance among published diagnostic comparisons. The absence of a true gold standard for detecting Giardia duodenalis also complicates diagnostic evaluations.

Objectives: To evaluate diagnostic tests commercially available in the United States for detecting Giardia duodenalis in dogs and cats, in comparison to a widely used reference test, the direct immunofluorescent assay (IFA), and also to compare the results of 2 methods of analysis: comparison of diagnostic tests to a reference test (IFA) and Bayesian analysis.

Animals: Fecal samples from a convenience sample of 388 cats and dogs located in Colorado, Oklahoma, and Virginia.

Methods: Fecal samples were tested for Giardia duodenalis by zinc sulfate centrifugal fecal flotation and 4 different commercial diagnostic immunoassays. Results were analyzed via Bayesian analysis and by comparison to the IFA as the reference test.

Results: Sensitivity and specificity by comparison to IFA was ≥82% and ≥90%, respectively, for all diagnostic tests in dogs and cats. When analyzed via Bayesian analysis, sensitivity and specificity were ≥83% and ≥95%, respectively. When ZnSO4 centrifugal fecal flotation results were combined with immunoassay results, there was no longer a significant difference between the sensitivities of the commercial in-clinic immunoassays.

Conclusion and clinical relevance: The Bayesian analysis validates using IFA as the reference test. Differences in commercial in-clinic immunoassay sensitivities can be mitigated when the results are combined with ZnSO4 centrifugal fecal flotation results.

Keywords: canine; direct immunofluorescent; fecal flotation; feline; immunoassay; protozoa.

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Conflict of interest statement

Anne M. Zajac has received honoraria from IDEXX and research support from TechLab, Inc. Meriam N. Saleh received travel funds and partial stipend support from TechLab, Inc. David S. Lindsay has received research support from IDEXX. Joel F. Herbein is currently an employee of TechLab, Inc, and at the time the research was conducted, Jack R. Heptinstall was employed by TechLab, Inc.

References

    1. Ballweber LR, Xiao LH, Bowman DD, Kahn G, Cama VA. Giardiasis in dogs and cats: update on epidemiology and public health significance. Trends Parasitol. 2010;26:180‐189. - PubMed
    1. Leib MS, Zajac AM. Giardiasis in dogs and cats. Vet Med. 1999;94:793.
    1. Thompson RCA, Palmer CS, O'Handley R. The public health and clinical significance of Giardia and Cryptosporidium in domestic animals. Vet J. 2008;177:18‐25. - PMC - PubMed
    1. Rishniw M, Liotta J, Bellosa M, Bowman D, Simpson KW. Comparison of 4 Giardia diagnostic tests in diagnosis of naturally acquired canine chronic subclinical giardiasis. J Vet Intern Med. 2010;24:293‐297. - PubMed
    1. Bowman DD. Georgis' Parasitology for Veterinarians. 10th ed. St. Louis, MO: Elsevier; 2014.

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