Abstract
Histoplasma capsulatum filamentous primary isolates and their subcultures are separable into two distinct colonial types (A and B) having different microscopic characteristics. Yeast forms of the A and B types and the parent (P) strains from which they are derived are microscopically indistinguishable. Critically standardized inocula of living P, A, and B yeasts from one strain of H. capsulatum (G-184) were injected intravenously into 12 rabbits. Each type produced progressively debilitating disease, but in varying degrees. Of the 12 animals, 6 died within 2 to 14 weeks. A persisting copious nasal exudate, beginning at or before 1 week, was cultured weekly at 26 C on Mycosel (BBL) agar. Pure cultures of A and B filamentous type colonies were recovered from exudates of animals receiving A and B yeasts, respectively, whereas both filamentous types were isolated from rabbits injected with P yeasts, with B predominating. Only A and B yeasts thus maintained their filamentous integrity during animal passage. It was noted that dissemination of H. capsulatum through the nares of infected rabbits represents a possible hazard to laboratory personnel heretofore unrecognized. It is also a possible means of cross-infecting or sensitizing or cross-infecting and sensitizing animals housed in the same room, if A and B yeasts prove not to be antigenically identical.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Berliner M. D. Primary subcultures of Histoplasma capsulatum. I. Macro and micro-morphology of the mycelial phase. Sabouraudia. 1968 Feb;6(2):111–118. [PubMed] [Google Scholar]
- Berliner M. D., Reca M. E. Vital staining of Histoplasma capsulatum with Janus Green B. Sabouraudia. 1966 Jun;5(1):26–29. [PubMed] [Google Scholar]
- Reca M. E. Reduction of a tetrazolium salt in determining growth activity of yeast-phase Histoplasma capsulatum. Appl Microbiol. 1968 Feb;16(2):236–238. doi: 10.1128/am.16.2.236-238.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]