Evaluation of an enzyme immunoassay for antibodies to a recombinant Blastomyces adhesin-1 repeat antigen as an aid in the diagnosis of blastomycosis in dogs

Alyssa C. Mourning Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

Search for other papers by Alyssa C. Mourning in
Current site
Google Scholar
PubMed
Close
 DVM
,
Edward E. Patterson Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

Search for other papers by Edward E. Patterson in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Emily J. Kirsch MiraVista Diagnostics, 4705 Decatur Blvd, Indianapolis, IN 42641.

Search for other papers by Emily J. Kirsch in
Current site
Google Scholar
PubMed
Close
 BS
,
Janelle S. Renschler MiraVista Diagnostics, 4705 Decatur Blvd, Indianapolis, IN 42641.

Search for other papers by Janelle S. Renschler in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Linda A. Wolf Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

Search for other papers by Linda A. Wolf in
Current site
Google Scholar
PubMed
Close
 DVM
,
Jasmin K. Paris Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

Search for other papers by Jasmin K. Paris in
Current site
Google Scholar
PubMed
Close
 BVSc
,
Michelle M. Durkin MiraVista Diagnostics, 4705 Decatur Blvd, Indianapolis, IN 42641.

Search for other papers by Michelle M. Durkin in
Current site
Google Scholar
PubMed
Close
 MS
, and
Lawrence J. Wheat MiraVista Diagnostics, 4705 Decatur Blvd, Indianapolis, IN 42641.

Search for other papers by Lawrence J. Wheat in
Current site
Google Scholar
PubMed
Close
 MD

Abstract

Objective—To evaluate the sensitivity and specificity of an enzyme immunoassay (EIA) for antibodies to a recombinant Blastomyces adhesin-1 repeat antigen (rBAD-1) to aid in the diagnosis of blastomycosis in dogs and compare the findings with results from other tests used for this purpose.

Design—Prospective analytic study.

Sample—Serum and urine from 70 dogs with and without blastomycosis.

Procedures—Serum and urine samples were collected from dogs with blastomycosis (n = 21), histoplasmosis (8), or nonfungal pulmonary disease (21) and from healthy control dogs living in a blastomycosis-endemic area (20). Serum was tested for antibodies against Blastomyces dermatitidis with the rBAD-1 antibody EIA and an A-antigen antibody agar gel immunodiffusion (AGID) assay. Serum and urine were tested for B dermatitidis antigen with a quantitative EIA.

Results—Sensitivity of the quantitative antigen EIA was 100% in serum and urine samples from dogs with blastomycosis, with specificity of 95% in urine samples from dogs with nonfungal pulmonary disease and 100% in urine samples from healthy dogs. Sensitivity of the rBAD-1 antibody EIA (95%) was significantly greater than that of the A-antigen antibody AGID assay (65%). Specificity of the antibody EIA was 88% in dogs with histoplasmosis, 95% in healthy dogs, and 100% in dogs with nonfungal pulmonary disease.

Conclusions and Clinical Relevance—The rBAD-1 antibody EIA had greater sensitivity than the A-antigen antibody AGID assay in dogs with blastomycosis. This antibody EIA may assist in distinguishing histoplasmosis from blastomycosis. Further evaluation in a larger prospective study is needed to verify these results.

Abstract

Objective—To evaluate the sensitivity and specificity of an enzyme immunoassay (EIA) for antibodies to a recombinant Blastomyces adhesin-1 repeat antigen (rBAD-1) to aid in the diagnosis of blastomycosis in dogs and compare the findings with results from other tests used for this purpose.

Design—Prospective analytic study.

Sample—Serum and urine from 70 dogs with and without blastomycosis.

Procedures—Serum and urine samples were collected from dogs with blastomycosis (n = 21), histoplasmosis (8), or nonfungal pulmonary disease (21) and from healthy control dogs living in a blastomycosis-endemic area (20). Serum was tested for antibodies against Blastomyces dermatitidis with the rBAD-1 antibody EIA and an A-antigen antibody agar gel immunodiffusion (AGID) assay. Serum and urine were tested for B dermatitidis antigen with a quantitative EIA.

Results—Sensitivity of the quantitative antigen EIA was 100% in serum and urine samples from dogs with blastomycosis, with specificity of 95% in urine samples from dogs with nonfungal pulmonary disease and 100% in urine samples from healthy dogs. Sensitivity of the rBAD-1 antibody EIA (95%) was significantly greater than that of the A-antigen antibody AGID assay (65%). Specificity of the antibody EIA was 88% in dogs with histoplasmosis, 95% in healthy dogs, and 100% in dogs with nonfungal pulmonary disease.

Conclusions and Clinical Relevance—The rBAD-1 antibody EIA had greater sensitivity than the A-antigen antibody AGID assay in dogs with blastomycosis. This antibody EIA may assist in distinguishing histoplasmosis from blastomycosis. Further evaluation in a larger prospective study is needed to verify these results.

Contributor Notes

Dr. Mourning's present address is Blue Pearl Veterinary Partners, 7717 Flying Cloud Dr, Eden Prairie, MN 55344.

Dr. Paris' present address is Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, Scotland.

Work was performed at the University of Minnesota College of Veterinary Medicine and MiraVista Diagnostics.

Emily J. Kirsch, Janelle S. Renschler, and Michelle M. Durkin are employed by MiraVista Diagnostics. Lawrence J. Wheat is president and current medical director of MiraVista Diagnostics.

Presented in abstract form at the 28th Annual American College of Veterinary Internal Medicine Forum, Anaheim, Calif, June 2010.

Selected samples were provided by Drs. Andrew Hanzlicek and Katherine KuKanich.

Address correspondence to Dr. Mourning (alyssa.thompson@bluepearlvet.com).
  • 1. Crews LJ, Feeney DA, Jessen CR, et al. Utility of diagnostic tests for and medical treatment of pulmonary blastomycosis in dogs: 125 cases (1989–2006). J Am Vet Med Assoc 2008;232:222227.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 2. Carlos WG, Rose AS, Wheat LJ, et al. Blastomycosis in Indiana: digging up more cases. Chest 2010;138:13771382.

  • 3. Spector D, Legendre AM, Wheat J, et al. Antigen and antibody testing for the diagnosis of blastomycosis in dogs. J Vet Intern Med 2008;22:839843.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4. Durkin MJ, Witt J, LeMonte A, et al. Antigen assay with the potential to aid in diagnosis of blastomycosis. J Clin Microbiol 2004;42:48734875.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5. Connolly P, Hage CA, Bariola JR, et al. Blastomyces dermatitidis antigen detection by quantitative enzyme immunoassay. Clin Vaccine Immunol 2012;19:5356.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 6. Foy DS, Trepanier LA, Kirsch EJ, et al. Serum and urine Blastomyces antigen concentrations as markers of clinical remission in dogs treated for systemic blastomycosis. J Vet Intern Med 2014;28:305310.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 7. Richer SM, Smedema ML, Durkin MM, et al. Development of a highly sensitive and specific blastomycosis antibody enzyme immunoassay using Blastomyces dermatitidis surface protein BAD-1. Clin Vaccine Immunol 2014;21:143146.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8. Hogan LH, Josvai S, Klien BS. Genomic cloning, characterization, and functional analysis of the major surface adhesion WI-1 on Blastomyces dermatitidis yeasts. J Biol Chem 1995;270:3072530732.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9. Brandhorts TT, Gauthier GM, Stein RA, et al. Calcium binding by the essential virulence factor BAD-1 of Blastomyces dermatitidis. J Biol Chem 2005;280:4215642163.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10. Klein BS, Hogan LH, Jones JM. Immunologic recognition of a 25-amino acid repeat arrayed in tandem on a major antigen of Blastomyces dermatitidis. J Clin Invest 1993;92:330337.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 11. Legendre AM, Becker PU. Evaluation of the agar-gel immunodiffusion test in the diagnosis of canine blastomycosis. Am J Vet Res 1980;41:21092111.

    • Search Google Scholar
    • Export Citation
  • 12. Martynowicz MA, Prakash UBS. Pulmonary blastomycosis—an appraisal of diagnostic techniques. Chest 2002;121:768773.

  • 13. Klein BC, Kuritsky JN, Chappell WA, et al. Comparison of the enzyme immunoassay, immunodiffusion, and complement fixation tests in detecting antibody in human serum to the A antigen of Blastomyces dermatitidis. Am Rev Respir Dis 1986;133:144148.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14. Klein BS, Squires RA, Lloyd JK, et al. Canine antibody response to Blastomyces dermatitidis WI-1 antigen. Am J Vet Res 2000;61:554558.

  • 15. Klein BS, Jones JM. Isolation, purification, and radiolabeling of a novel 120-kD surface protein on Blastomyces dermatitidis yeasts to detect antibody in infected patients. J Clin Invest 1990;85:152161.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 16. Boyd AR, Vandyke JL, Scalarone GM. Blastomyces dermatitidis yeast lysate antigen combinations: antibody detection in dogs with blastomycosis. Vet Med Int 2013;2013:940126.

    • Search Google Scholar
    • Export Citation

Advertisement