Connie F. Cañete-Gibas

Environmental fungi may be recovered from traumatic wounds following motor vehicle collisions (MVCs), but distinguishing transient environmental inoculation, colonization, or contamination from true fungal infection can be challenging. Diagnostic challenges arise when fungal isolates recovered from clinical specimens remain non-sporulating (i.e., sterile), limiting conventional morphological identification and potentially remaining unidentified by routine laboratory platforms such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). We describe two cases involving the recovery and diagnostic characterization of Subramaniula asteroides and Aspergillus quadrilineatus from traumatic wounds following MVC-related polytrauma in the United Arab Emirates. In Case 1, a 55-year-old man with a severe crush–degloving hand injury underwent infectious disease evaluation for a suspected complicated skin and soft tissue infection (SSTI), prompting wound culture and antibacterial therapy. The recovered non-sporulating mold was identified as S. asteroides by ITS and D1/D2 sequencing and phylogenetic analysis; histopathologic assessment for fungal tissue invasion was not performed, no antifungal therapy was documented, and the wound improved following surgical and antibacterial management. In Case 2, a 40-year-old man with extensive upper-limb trauma underwent debridement and skin grafting, with wound culture yielding an initially non-sporulating mold subsequently identified as A. quadrilineatus by multilocus analysis of ITS, β-tubulin, and calmodulin. Voriconazole was initiated following communication of the species-level identification and discontinued after 15 days when the isolate was considered more likely to represent colonization or contamination than true wound infection. Although invasive fungal disease was not established in either case, these reports highlight the diagnostic challenges posed by non-sporulating molds, particularly in distinguishing fungal recovery from true infection in traumatic wounds. They also demonstrate the value of reference mycology laboratories integrating phenotypic and molecular approaches in accurately identifying uncommon environmental fungi and informing the interpretation of their clinical significance.

Aspergillus section Terrei consists of numerous cryptic species in addition to A. terreus sensu stricto. The treatment of invasive infections caused by these fungi may pose a unique challenge prior to diagnosis and species identification, in that they are often clinically resistant to amphotericin B, with poor outcomes and low survival rates in patients treated with this polyene. Data on the species distributions and susceptibility profiles of isolates within section Terrei from the United States (U.S.) are limited. Here, we report the species distributions and susceptibility profiles for amphotericin B, isavuconazole, itraconazole, posaconazole, voriconazole, and micafungin against 278 clinical isolates of this section from institutions across the U.S. collected over a 52-month period. Species identification was performed by DNA sequence analysis and phenotypic characterization. Susceptibility testing was performed using the CLSI broth microdilution method. The majority of isolates were identified as Aspergillus terreus sensu stricto (69.8%), although several other cryptic species were also identified. Most were cultured from specimens collected from the respiratory tract. Posaconazole demonstrated the most potent activity of the azoles (MIC range ≤ 0.03–1 mg/L), followed by itraconazole (≤0.03–2 mg/L), voriconazole, and isavuconazole (0.125–8 mg/L for each). Amphotericin B demonstrated reduced in vitro susceptibility against this section (MIC range 0.25–8 mg/L), although this appeared to be species-dependent. A new species within this section, A. pseudoalabamensis, is also described. Our results, which are specific to the U.S., are similar to previous surveillance studies of the Aspergillus section Terrei.

Phaeohyphomycosis caused by Exophiala species represents an important disease of concern for farmed and aquarium-housed fish. The objective of this study was to summarize the clinical findings and diagnosis of Exophiala infections in aquarium-housed Cyclopterus lumpus. Clinical records and postmortem pathology reports were reviewed for 15 individuals from 5 public aquaria in the United States and Canada from 2007 to 2015. Fish most commonly presented with cutaneous ulcers and progressive clinical decline despite topical or systemic antifungal therapy. Antemortem fungal culture of cutaneous lesions resulted in colonial growth for 7/12 samples from 8 individuals. Amplification of the internal transcribed spacer region (ITS) of nuclear rDNA identified Exophiala angulospora or Exophiala aquamarina in four samples from three individuals. Postmortem histopathologic findings were consistent with phaeohyphomycosis, with lesions most commonly found in the integument (11/15), gill (9/15), or kidney (9/15) and evidence of fungal angioinvasion and dissemination. DNA extraction and subsequent ITS sequencing from formalin-fixed paraffin-embedded tissues of seven individuals identified E. angulospora, E. aquamarina, or Cyphellophora sp. in four individuals. Lesion description, distribution, and Exophiala spp. identifications were similar to those reported in farmed C. lumpus. Antemortem clinical and diagnostic findings of phaeohyphomycosis attributable to several species of Exophiala provide insight on the progression of Exophiala infections in lumpfish that may contribute to management of the species in public aquaria and under culture conditions.

Fungal taxonomy is the branch of mycology by which we classify and group fungi based on similarities or differences. Historically, this was done by morphologic characteristics and other phenotypic traits. However, with the advent of the molecular age in mycology, phylogenetic analysis based on DNA sequences has replaced these classic means for grouping related species. This, along with the abandonment of the dual nomenclature system, has led to a marked increase in the number of new species and reclassification of known species. Although these evaluations and changes are necessary to move the field forward, there is concern among medical mycologists that the rapidity by which fungal nomenclature is changing could cause confusion in the clinical literature. Thus, there is a proposal to allow medical mycologists to adopt changes in taxonomy and nomenclature at a slower pace. In this review, changes in the taxonomy and nomenclature of medically relevant fungi will be discussed along with the impact this may have on clinicians and patient care. Specific examples of changes and current controversies will also be given.