Scopulariopsis, a Poorly Known Opportunistic Fungus: Spectrum of Species in Clinical Samples and In Vitro Responses to Antifungal Drugs

Abstract

dNinety-nine isolates of clinical origin, tentatively identified as Scopulariopsis or Microascus, were morphologically and molecularly characterized by a combined analysis of the D1/D2 domains of the 28S rRNA gene and a fragment of the elongation factor 1-␣ gene (EF1-␣) sequences. The most prevalent species was Scopulariopsis brevicaulis (49.4%), followed by Scopulariopsis gracilis (14.4%), Scopulariopsis brumptii (7.2%), Microascus cinereus (5.2%), the Scopulariopsis candida species complex (3.1%), and Microascus cirrosus (2.1%). The most common anatomic sites of isolation were the respiratory tract (61.6%), superficial tissue (19.2%), and deep tissue or fluid samples (19.2%). The antifungal susceptibilities of the isolates to eight drugs were tested in vitro, with all the drugs generally showing poor activity.

Fatal Scopulariopsis brumptii in a Pediatric Immunocompromised Host

“…Molecular tools including ribosomal RNA targets are used for speciation [2,9,12], but the lack of reference material leads to potential misidentificaiton [2]. Experienced medical mycologists are skilled in identification of Scopularioposis spp, and assisted in the fungal identification in this case.…”

“…The annellides are thick walled and appear more flask-like in S. brumptii as opposed to the cylindrical annellides of S. brevicaulis [11]. Rounded to lemon shaped conidial structures appear within five to seven days forming loose chains from the annellide apices and are used for primary identification [2,9]. The conidia of S. brevicaulis are slightly larger than those of S. brumptii, and the conidia of S. brumptii have a darker black-brown color as compared to S. brevicualis which are hyaline to pale brown [11].…”

“…Immunocompetent Scopulariopsis spp. infections are superficial cutaneous, most commonly nondermatophytic onychomycoses from S. brevicaulis infection [2]. Immunosuppressed individuals may manifest deep tissue and disseminated infections including pneumonia, endophthalmitis, invasive sinusitis, peritonitis, and endocarditis [2,9].…”

“…infections are superficial cutaneous, most commonly nondermatophytic onychomycoses from S. brevicaulis infection [2]. Immunosuppressed individuals may manifest deep tissue and disseminated infections including pneumonia, endophthalmitis, invasive sinusitis, peritonitis, and endocarditis [2,9]. Risk factors include severe neutropenia (absolute neutrophil count <500 cells/mL for >1 week), vascular and urinary catheterization, gastrointestinal or oropharyngeal mucosal disruption by chemotherapy, broad-spectrum antibiotic use and high dose corticosteroids [1].…”

“…Genus Scopulariopsis contain hyaline and dematiaceous nondermatophytic filamentous molds [1], saprobes common in soil, plant debris, animal remains, and moist indoor environments [2,9]. With 40 recognized species, few are responsible for human disease [2]. Immunocompetent Scopulariopsis spp.…”