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First Report of Human Infection Caused by Aspergillus steynii and Analysis of Its Whole-Genome Characteristics
Ruixuan Wang1, Jingjing Chen1, Na Wu2
1National Clinical Research Center for Medical Auxiliary Technology (Laboratory Medicine), Department of Laboratory Medicine, The First Hospital of China Medical University, Shenyang, China, cmu.edu.cn.
Abstract:
The incidence of infections caused by rare pathogens has increased in recent years. This necessitates the development of effective diagnostic and therapeutic approaches. In this study, we report the first documented case of Aspergillus steynii-induced pulmonary infection in humans. We evaluated the morphological and molecular characteristics of this fungus to elucidate its role in human infections. A 47-year-old woman with immunosuppression after bone marrow transplantation developed symptoms of pulmonary infection. The pathogen was identified as A. steynii through culture techniques, microscopy, mass spectrometry, multigene molecular identification, and whole-genome sequencing. Antifungal susceptibility testing was performed, and comparative genomic analysis was conducted to assess the phylogenetic relationship and genomic characteristics of A. steynii and other pathogenic Aspergillus species. Genomic analysis revealed a high degree of similarity with other pathogenic Aspergillus species. Furthermore, we identified 470 unique gene families primarily associated with ABC transporter pathways linked to multidrug resistance. The strain was sensitive to triazoles and echinocandins but exhibited elevated minimum inhibitory concentrations (MICs) for amphotericin B, flucytosine, and fluconazole. In addition, multiple potential drug resistance genes were identified, indicating the potential for multidrug resistance. The emergence of A. steynii in humans poses new clinical challenges and risks, including cross-species transmission and multidrug resistance. The potential for A. steynii infections, particularly in immunosuppressed patients, highlights the importance of early diagnosis and timely intervention to reduce the risk of misdiagnosis or delayed treatment. Thus, our findings have the potential to improve the clinical and differential diagnosis of this infection and facilitate the development of effective therapeutic approaches.
Insights
This study documents the first human pulmonary infection caused by Aspergillus steynii in an immunocompromised patient. Early diagnosis and treatment are crucial due to potential multidrug resistance in this rare fungal pathogen.
Area of Science:
- Medical Mycology
- Infectious Diseases
- Genomics
Background:
- Increasing incidence of infections by rare pathogens requires novel diagnostic and therapeutic strategies.
- Immunosuppressed individuals, such as bone marrow transplant recipients, are at higher risk for opportunistic infections.
- The emergence of new fungal pathogens poses significant clinical challenges.
Purpose of the Study:
- To report the first documented case of human pulmonary infection caused by Aspergillus steynii.
- To characterize the morphological and molecular features of Aspergillus steynii.
- To investigate the antifungal susceptibility and genomic basis of drug resistance in Aspergillus steynii.
Main Methods:
- Identification of the causative agent using culture, microscopy, mass spectrometry, and multigene sequencing.
- Whole-genome sequencing for comprehensive genomic analysis and phylogenetic comparison.
- Antifungal susceptibility testing (AST) and comparative genomic analysis to identify drug resistance mechanisms.
Main Results:
- Aspergillus steynii was identified as the cause of pulmonary infection in an immunosuppressed patient.
- Genomic analysis revealed high similarity to other pathogenic Aspergillus species and identified 470 unique gene families linked to multidrug resistance.
- The isolate showed sensitivity to triazoles and echinocandins but elevated MICs for amphotericin B, flucytosine, and fluconazole, with potential for multidrug resistance.
Conclusions:
- Aspergillus steynii represents a novel opportunistic pathogen capable of causing severe pulmonary infections in immunocompromised hosts.
- The identification of multidrug resistance-associated genes highlights the potential for treatment challenges.
- Early diagnosis and targeted therapeutic approaches are essential for managing Aspergillus steynii infections.
