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Isolation of Blastomyces dermatitidis from pigeon manure
Abstract:
We recently diagnosed and treated a 45-year-old white male horticulturist with acute progressive blastomycosis. Epidemiologic studies revealed that the patient used a load of pigeon manure as fertilizer approximately 6 weeks before becoming ill. He used the pigeon manure only once, resealed the remainder, and stored it in his hothouse. Samples of the pigeon guano were digested with 10 per cent KOH, and the characteristic yeast forms of Blastomyces dermatitidis were seen in large numbers. The fungus was cultured from another sample of the same material. This is the first time that the pathogenic fungus B. dermatitidis has been isolated from the environment in association with a human case.
Insights
A horticulturist contracted blastomycosis after handling pigeon manure. This is the first isolation of Blastomyces dermatitidis from environmental pigeon guano linked to a human case.
Area of Science:
- Medical Mycology
- Environmental Microbiology
- Infectious Diseases
Background:
- Blastomycosis is a serious fungal infection caused by Blastomyces dermatitidis.
- Exposure to contaminated soil and decaying organic matter is a known risk factor.
- Identifying environmental sources is crucial for understanding transmission routes.
Observation:
- A 45-year-old male horticulturist developed acute, progressive blastomycosis.
- Epidemiological investigation linked his illness to the use of pigeon manure as fertilizer.
- The patient had stored remaining pigeon guano in his hothouse.
Findings:
- Microscopic examination of pigeon guano samples revealed numerous yeast forms of Blastomyces dermatitidis.
- Blastomyces dermatitidis was successfully cultured from the same environmental sample.
- This marks the first documented isolation of B. dermatitidis from environmental pigeon manure associated with a human case.
Implications:
- Pigeon manure represents a potential environmental reservoir for Blastomyces dermatitidis.
- This finding highlights a novel transmission pathway for blastomycosis.
- Further research into fungal presence in avian-related environments is warranted to prevent human infections.
