Utility of diagnostic tests for and medical treatment of pulmonary blastomycosis in dogs: 125 cases (1989–2006)

Laura J. Crews Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

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Daniel A. Feeney Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

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Carl R. Jessen Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

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Allison B. Newman Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.

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

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Abstract

Objective—To compare results of the most common diagnostic tests for pulmonary blastomycosis in dogs, identify factors associated with outcome, and determine response to various antifungal treatment protocols.

Design—Retrospective case series.

Animals—125 dogs with pulmonary blastomycosis.

Procedures—Medical records were reviewed, and information was obtained regarding diagnostic methods, results of routine laboratory testing, and radiographic response to antifungal treatment.

Results—79 dogs survived, 38 died, and 8 were euthanized. Transthoracic fine-needle aspiration and transtracheal lavage were the most common diagnostic methods. Results of an agar gel immunodiffusion test for antibodies against Blastomyces dermatitidis were negative in 12 of 24 (50%) dogs. Only 3 of 94 (3.2%) dogs in which cytologic or histologic examination or bacterial culture of pulmonary samples were performed had any evidence of concurrent bacterial infection. The half-time for radiographic resolution of pulmonary infiltrates did not vary significantly with antifungal treatment, and use of a loading dosage of itraconazole was not associated with significant improvements in outcome or time to disease resolution. Dogs that died had a higher number of band neutrophils at initial examination, compared with those that survived.

Conclusions and Clinical Relevance—Results suggested that the agar gel immunodiffusion test should not be used as the sole diagnostic test for pulmonary blastomycosis in dogs, that concurrent bacterial pneumonia was uncommon in dogs with pulmonary blastomycosis, and that the rate with which pulmonary infiltrates resolved did not vary significantly among antifungal treatments.

Abstract

Objective—To compare results of the most common diagnostic tests for pulmonary blastomycosis in dogs, identify factors associated with outcome, and determine response to various antifungal treatment protocols.

Design—Retrospective case series.

Animals—125 dogs with pulmonary blastomycosis.

Procedures—Medical records were reviewed, and information was obtained regarding diagnostic methods, results of routine laboratory testing, and radiographic response to antifungal treatment.

Results—79 dogs survived, 38 died, and 8 were euthanized. Transthoracic fine-needle aspiration and transtracheal lavage were the most common diagnostic methods. Results of an agar gel immunodiffusion test for antibodies against Blastomyces dermatitidis were negative in 12 of 24 (50%) dogs. Only 3 of 94 (3.2%) dogs in which cytologic or histologic examination or bacterial culture of pulmonary samples were performed had any evidence of concurrent bacterial infection. The half-time for radiographic resolution of pulmonary infiltrates did not vary significantly with antifungal treatment, and use of a loading dosage of itraconazole was not associated with significant improvements in outcome or time to disease resolution. Dogs that died had a higher number of band neutrophils at initial examination, compared with those that survived.

Conclusions and Clinical Relevance—Results suggested that the agar gel immunodiffusion test should not be used as the sole diagnostic test for pulmonary blastomycosis in dogs, that concurrent bacterial pneumonia was uncommon in dogs with pulmonary blastomycosis, and that the rate with which pulmonary infiltrates resolved did not vary significantly among antifungal treatments.

Contributor Notes

Address correspondence to Dr. Feeney.
  • 1.

    Hawkins EC, DeNicola DB. Cytologic analysis of tracheal wash specimens and bronchoalveolar lavage fluid in the diagnosis of mycotic infections in dogs. J Am Vet Med Assoc 1990;197:7983.

    • Search Google Scholar
    • Export Citation
  • 2.

    Roudebush P, Green RA, Digilio KM. Percutaneous fine-needle aspiration biopsy of the lung in disseminated pulmonary disease. J Am Anim Hosp Assoc 1981;17:109116.

    • Search Google Scholar
    • Export Citation
  • 3.

    Wood EF, O'Brien RT, Young KM. Ultrasound-guided fine-needle aspiration of focal parenchymal lesions of the lungs in dogs and cats. J Vet Intern Med 1998;12:338342.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4.

    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
  • 5.

    Kerl ME. Update on canine and feline fungal diseases. Vet Clin North Am Small Anim Pract 2003;33:721747.

  • 6.

    Legendre AM, Rohrbach BW, Toal RL, et al. Treatment of blastomycosis with itraconazole in 112 dogs. J Vet Intern Med 1996;10:365371.

  • 7.

    Legendre AM, Selcer BA, Edwards DF, et al. Treatment of canine blastomycosis with amphotericin B and ketoconazole. J Am Vet Med Assoc 1984;184:12491254.

    • Search Google Scholar
    • Export Citation
  • 8.

    Crews LJ, Feeney DA, Jessen CR, et al. Radiographic findings in dogs with pulmonary blastomycosis: 125 cases (1989–2006). J Am Vet Med Assoc 2008;232:215221.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9.

    Meuten DJ, Chew DJ, Capen CC, et al. Relationship of serum total calcium to albumin and total protein in dogs. J Am Vet Med Assoc 1982;180:6367.

    • Search Google Scholar
    • Export Citation
  • 10.

    Arceneaux KA, Taboada J, Hosgood G. Blastomycosis in dogs: 115 cases (1980–1995). J Am Vet Med Assoc 1998;213:658664.

  • 11.

    Legendre AM, Walker M, Buyukmihci N, et al. Canine blastomycosis: a review of 47 clinical cases. J Am Vet Med Assoc 1981;178:11631168.

  • 12.

    Klein BS, Squires RA, Foyer Lloyd JK, et al. Canine antibody response to Blastomyces dermatitidis WI-1 antigen. Am J Vet Res 2000;61:554558.

  • 13.

    Ferguson DC, Hoenig M. Endocrine system. In: Latimer KS, Mahaffey EA, Prasse KW, eds. Duncan and Prasse's veterinary laboratory medicine: clinical pathology. Ames, Iowa: Iowa State Press, 2003;270303.

    • Search Google Scholar
    • Export Citation
  • 14.

    Church D. Electrolyte disorders. In: Ettinger SJ, Feldman EC, eds. Textbook of veterinary internal medicine. 6th ed. St Louis: Elsevier Saunders Co, 2005;236240.

    • Search Google Scholar
    • Export Citation
  • 15.

    Dow SW, Legendre AM, Stiff M, et al. Hypercalcemia associated with blastomycosis in dogs. J Am Vet Med Assoc 1986;188:706709.

  • 16.

    Crews LJ, Sharkey LC, Feeney DA, et al. Evaluation of total and ionized calcium status in dogs with blastomycosis: 38 cases (1997–2006). J Am Vet Med Assoc 2007;231:15451549.

    • Crossref
    • Search Google Scholar
    • Export Citation

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