Blastomycosis: Report of the first case from Alberta, Canada

Abstract

The first known case of laboratory confirmed blastomycosis in Alberta occurred in 1970. The patient, who is believed never to have left Alberta, presented with of headaches, sore neck and impaired intellect. Initially, tuberculous or cryptococcal meningitis was suspected, but laboratory findings did not support the diagnosis. A fungus resembling Blastomyces dermatitidis was isolated from the venticular cerebrospinal fluid and lung at autopsy. A few yeast cells suggestive of B. dermatitidis were seen in lung and brain tissue sections. Initial attempts at in vitro conversion of the mycelial form of the isolate into yeast form on several enriched media were unsuccessful. The fungus gave +/- to ++ reactions B. dermatitidis specific conjugate by the direct fluorescent antibody technique, it was not pathogenic for mice and guinea pigs, and no asexual spores were produced in slide cultures. Further investigation indicated that the mycelial form of the fungus converted into its yeast form when an actively growing inoculum was used, although the yeast cells varied considerably in size. The yeast form produced disseminated infection in mice within 10 days. Exoantigenic analysis demonstrated an 'A' antigen specific for B. dermatitidis, which revealed the identity of this organism as an atypical strain of B. dermatitidis.

Phylogeny, ecology and taxonomy of systemic pathogens and their relatives in Ajellomycetaceae (Onygenales): Blastomyces, Emergomyces, Emmonsia, Emmonsiellopsis

“…After prolonged incubation (4-5 weeks) at 24-27°C some dumbbell-shaped, spherical or ovoidal conidium-like cells were produced on MEA (Fig. 11E), consistent with observations of Sekhon et al (1982) who mentioned dumbbell-shaped conidia after several weeks on cereal agar at 25°C. The latter author reported the infection caused by strain CBS 139874 as a case of blastomycosis.…”

“…Blastomyces helicus infection appears to primarily cause disease in immune compromised persons (Sekhon et al 1982;Kappagoda et al 2017;Schwartz et al 2017;Rofael et al 2018). Conidia are not produced in vitro, and thus the risk of occupational inhalational exposure is considered low, although primary inoculation disease, may be possi- ble.…”

Name Changes for Fungi of Medical Importance, 2016–2017

“…A second clade contains a novel species, named Blastomyces percursus, which has been recovered from immunocompetent and immunocompromised individuals in Israel and South Africa and had previously been identified as Blastomyces dermatitidis (3,4). The third clade comprised a strain, isolated in 1970, from a patient from Alberta, Canada, with what was described as an unusual case of blastomycosis (8). In 2015, Sigler (9) determined that the isolate from this case 3proposed that E. parva should be renamed Blastomyces parvus, but this taxon was not validated until 2018 (4).…”

50 Years of Emmonsia Disease in Humans: The Dramatic Emergence of a Cluster of Novel Fungal Pathogens

“…The earliest recorded case, from 1970, was reported as an unusual case of blastomycosis in a patient from Alberta, Canada, a region considered non-endemic for this disease [ 12 ]. The patient presented with neurological symptoms; at autopsy, histopathology sections revealed atypical yeast-like cells in lung and brain, and a fungus resembling Blastomyces dermatitidis was isolated from cerebral spinal fluid and lung.…”