South American Blastomycosis Workup

  • Author: Julie E Dixon, MD, FAAD; Chief Editor: Dirk M Elston, MD   more...
 
Updated: Jan 24, 2012
 

Laboratory Studies

  • Direct examination
    • The diagnosis of South American blastomycosis often is made recognizing the fungus on wet preparations.
    • The microscopic examination of pus or superficial scrapings from mucosal lesions reveals thick-walled spherical yeast cells with multiple peripheral buds encircling a mother cell (ie, pilot's wheal or mariner's wheal).
    • This pilot's wheel configuration measures as long as 60 µm in diameter and is highly characteristic of P brasiliensis.
    • If microscopic examination does not reveal spores with multiple buds, fungal culturing may be necessary to differentiate the organism from other fungal pathogens.
  • Culturing
    • Cultures on Sabouraud agar at room temperature yield the mold in 3-4 weeks.
    • P brasiliensis is a slowly growing mold with a white-to-tan aerial mycelium.
    • Subcultures on rich media at 37°C yield the characteristic yeast form.
  • Skin testing
    • The paracoccidioidin skin test is available but has little diagnostic value.
    • A positive skin test result indicates prior exposure, but it does not necessarily indicate current disease.
    • The test may be useful prognostically because the conversion from an anergic result to a positive result is associated with a good prognosis in patients with severe South American blastomycosis.
  • Serologic testing
    • Immunodiffusion and complement fixation are useful for the diagnosis of South American blastomycosis.
    • Results with both tests are positive in about 85-95% of patients with active disease, although cross-reactions with histoplasmosis can occur.
    • Complement fixation is quantitative and, therefore, is useful for following disease progression and response to therapy.
    • Recently, monoclonal antibodies to antigenic compounds of P brasiliensis (43-kd and 70-kd glycoproteins) have been developed. Using inhibition enzyme-linked immunosorbent assays, the sensitivity and specificity of these antibodies exceed 95%. These tests may prove useful for diagnosing South American blastomycosis in anergic or immunocompromised patients and for monitoring response to treatment.[13, 14, 15]
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Imaging Studies

  • If clinically indicated, a chest radiograph should be obtained. A chest radiograph often shows opaque bilateral lesions that are generally nodular but sometimes cavitary. Lesions usually involve the perihilar and basilar portions of the lungs. This finding can help to differentiate South American blastomycosis from tuberculosis, which has a propensity to involve the upper lobes of the lungs.
  • If clinically indicated, computed tomography or magnetic resonance imaging of the brain should be obtained to evaluate central nervous system involvement.
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Other Tests

  • If warranted, pulmonary function tests may reveal obstructive abnormalities, but the results are generally mild compared with the radiographic findings.
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Procedures

  • Lesional biopsies are helpful in diagnosis.
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Histologic Findings

Histologic examination reveals a granulomatous reaction with epithelioid and giant cells in association with a severe inflammatory infiltrate. Spores with the characteristic pilot's wheel may be found within giant cells or free in the inflammatory infiltrate. In skin and mucous membrane lesions, pseudoepitheliomatous hyperplasia with intraepidermal abscesses occurs. Caseous necrosis is seen within the lymph nodes. Tissue repair is seen as collagen fibrosis.

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Contributor Information and Disclosures
Author

Julie E Dixon, MD, FAAD  Private Practice, Ironwood Dermatology, Tucson, Arizona

Julie E Dixon, MD, FAAD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, and American Medical Association

Disclosure: Nothing to disclose.

Coauthor(s)

Norman Levine  MD, Private practice, Tucson, AZ

Norman Levine is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Specialty Editor Board

Franklin Flowers, MD  Chief, Division of Dermatology, Professor, Department of Medicine and Otolaryngology, Affiliate Associate Professor of Pediatrics and Pathology, University of Florida College of Medicine

Franklin Flowers, MD, is a member of the following medical societies: American College of Mohs Micrographic Surgery and Cutaneous Oncology

Disclosure: Nothing to disclose.

David F Butler, MD  Professor of Dermatology, Texas A&M University College of Medicine; Chair, Department of Dermatology, Director, Dermatology Residency Training Program, Scott and White Clinic, Northside Clinic

David F Butler, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, American Society for Dermatologic Surgery, American Society for MOHS Surgery, Association of Military Dermatologists, and Phi Beta Kappa

Disclosure: Nothing to disclose.

Jeffrey J Miller, MD  Associate Professor of Dermatology, Pennsylvania State University College of Medicine; Staff Dermatologist, Pennsylvania State Milton S Hershey Medical Center

Jeffrey J Miller, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, Association of Professors of Dermatology, North American Hair Research Society, and Society for Investigative Dermatology

Disclosure: Nothing to disclose.

Catherine M Quirk, MD  Clinical Assistant Professor, Department of Dermatology, University of Pennsylvania

Catherine M Quirk, MD is a member of the following medical societies: Alpha Omega Alpha and American Academy of Dermatology

Disclosure: Nothing to disclose.

Chief Editor

Dirk M Elston, MD  Director, Ackerman Academy of Dermatopathology, New York

Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

References

  1. Lupi O, Tyring SK, McGinnis MR. Tropical dermatology: fungal tropical diseases. J Am Acad Dermatol. Dec 2005;53(6):931-51, quiz 952-4. [Medline].

  2. Benard G, Kavakama J, Mendes-Giannini MJ, Kono A, Duarte AJ, Shikanai-Yasuda MA. Contribution to the natural history of paracoccidioidomycosis: identification of the primary pulmonary infection in the severe acute form of the disease--a case report. Clin Infect Dis. Jan 1 2005;40(1):e1-4. [Medline].

  3. Mayr A, Kirchmair M, Rainer J, Rossi R, et al. Chronic paracoccidioidomycosis in a female patient in Austria. Eur J Clin Microbiol Infect Dis. Dec 2004;23(12):916-9. [Medline].

  4. Maluf ML, Pereira SR, Takahachi G, Svidzinski TI. [Prevalence of paracoccidioidomycosis infection determined by sorologic test in donors' blood in the Northwest of Parana, Brazil]. Rev Soc Bras Med Trop. Jan-Feb 2003;36(1):11-6. [Medline].

  5. Cabral-Marques O, Schimke LF, Pereira PV, Falcai A, de Oliveira JB, Hackett MJ, et al. Expanding the Clinical and Genetic Spectrum of Human CD40L Deficiency: The Occurrence of Paracoccidioidomycosis and Other Unusual Infections in Brazilian Patients. J Clin Immunol. Dec 23 2011;[Medline].

  6. Nogueira LM, Santos M, Ferreira LC, Talhari C, Rodrigues RR, Talhari S. AIDS-associated paracoccidioidomycosis in a patient with a CD4+ T-cell count of 4 cells/mm³. An Bras Dermatol. Jul-Aug 2011;86(4 Suppl 1):S129-32. [Medline].

  7. Desjardins CA, Champion MD, Holder JW, Muszewska A, Goldberg J, Bailão AM, et al. Comparative genomic analysis of human fungal pathogens causing paracoccidioidomycosis. PLoS Genet. Oct 2011;7(10):e1002345. [Medline]. [Full Text].

  8. Blotta MH, Mamoni RL, Oliveira SJ, et al. Endemic regions of paracoccidioidomycosis in Brazil: a clinical and epidemiologic study of 584 cases in the southeast region. Am J Trop Med Hyg. Sep 1999;61(3):390-4. [Medline].

  9. Pereira RM, Tresoldi AT, da Silva MT, Bucaretchi F. Fatal disseminated paracoccidioidomycosis in a two-year-old child. Rev Inst Med Trop Sao Paulo. Jan-Feb 2004;46(1):37-9. [Medline].

  10. Sant'Anna GD, Mauri M, Arrarte JL, Camargo H Jr. Laryngeal manifestations of paracoccidioidomycosis (South American blastomycosis). Arch Otolaryngol Head Neck Surg. Dec 1999;125(12):1375-8. [Medline].

  11. de Almeida SM, Queiroz-Telles F, Teive HA, Ribeiro CE, Werneck LC. Central nervous system paracoccidioidomycosis: clinical features and laboratorial findings. J Infect. Feb 2004;48(2):193-8. [Medline].

  12. Corti M, Villafane MF, Negroni R, Palmieri O. Disseminated paracoccidioidomycosis with peripleuritis in an AIDS patient. Rev Inst Med Trop Sao Paulo. Jan-Feb 2004;46(1):47-50. [Medline].

  13. Marques da Silva SH, Queiroz-Telles F, Colombo AL, Blotta MH, Lopes JD, Pires De Camargo Z. Monitoring gp43 antigenemia in Paracoccidioidomycosis patients during therapy. J Clin Microbiol. Jun 2004;42(6):2419-24. [Medline].

  14. Yasuda MA. Pharmacological management of paracoccidioidomycosis. Expert Opin Pharmacother. Mar 2005;6(3):385-97. [Medline].

  15. da Silva SH, Grosso Dde M, Lopes JD, et al. Detection of Paracoccidioides brasiliensis gp70 circulating antigen and follow-up of patients undergoing antimycotic therapy. J Clin Microbiol. Oct 2004;42(10):4480-6. [Medline].

  16. Hay RJ. Antifungal drugs used for systemic mycoses. Dermatol Clin. Jul 2003;21(3):577-87. [Medline].

  17. Queiroz-Telles F, Goldani LZ, Schlamm HT, Goodrich JM, Espinel-Ingroff A, Shikanai-Yasuda MA. An open-label comparative pilot study of oral voriconazole and itraconazole for long-term treatment of paracoccidioidomycosis. Clin Infect Dis. Dec 1 2007;45(11):1462-9. [Medline].

  18. Travassos LR, Taborda CP, Colombo AL. Treatment options for paracoccidioidomycosis and new strategies investigated. Expert Rev Anti Infect Ther. Apr 2008;6(2):251-62. [Medline].

  19. Ollague JM, de Zurita AM, Calero G. Paracoccidioidomycosis (South American blastomycosis) successfully treated with terbinafine: first case report. Br J Dermatol. Jul 2000;143(1):188-91. [Medline].

  20. Crissey JT, Lang H, Parish LC. Manual of Medical Mycology. Cambridge, Mass: Blackwell Sciences; 1995:128-34.

  21. Elder D, Elenitsas E, Jawarsky C, et al, eds. Lever's Histopathology of the Skin. 10th ed. Philadelphia, Pa: Lippincott-Raven; 2008.

  22. Guerrant RL, Walker DH, Weller PF, eds. Tropical Infectious Diseases: Principles, Pathogens, and Practice. 2nd ed. New York, NY: Churchill Livingstone; 2006.

  23. Richardson MD, Warnock DW, eds. Fungal Infection: Diagnosis and Management. 3rd ed. London, England: Bailliere Tindallk; 2003.

  24. Stickland GT, ed. Hunter's Tropical Medicine and Emerging Infectious Diseases. 8th ed. Philadelphia, Pa: WB Saunders; 2000:559-61.

 
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Crusted plaques over the central part of the face in a man with South American blastomycosis. Courtesy of Rolando Vasquez, MD, Professor of Dermatology, Guatemala.
Ulcerated nodule on the tongue in a man with South American blastomycosis. Courtesy of Heidi Logemann, Professor of Mycology, Universidad de San Carlos, Guatemala.
 
 
 
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