From the Guidelines
Aspergillus fumigatus is a common environmental mold that primarily causes respiratory infections in humans, and its role is to produce tiny airborne spores that can cause serious infections in individuals with weakened immune systems, leading to invasive aspergillosis, allergic bronchopulmonary aspergillosis, and aspergillomas. The fungus is particularly dangerous because it thrives at human body temperature, produces various toxins, and has enzymes that help it evade immune defenses 1. In immunocompromised patients, A. fumigatus can cause invasive aspergillosis, a potentially fatal condition where the fungus invades lung tissue and potentially spreads to other organs 1. Some key points to consider about A. fumigatus include:
- It is a common cause of invasive aspergillosis in immunocompromised patients 1
- It can cause allergic bronchopulmonary aspergillosis in people with asthma or cystic fibrosis, triggering severe allergic reactions in the lungs 1
- It can form fungal balls called aspergillomas in pre-existing lung cavities 1
- Treatment typically involves antifungal medications like voriconazole, but prevention through HEPA filtration and avoiding areas with high mold concentrations is crucial for vulnerable individuals 1
- Granulocyte transfusions may be another resource for the treatment of patients with invasive pulmonary aspergillosis, but this modality is controversial and associated with transfusion reactions and transmission of cytomegalovirus infection 1
From the FDA Drug Label
In clinical trials, the majority of isolates recovered were Aspergillus fumigatus There was a small number of cases of culture-proven disease due to species of Aspergillus other than A. fumigatus
The role of Aspergillus fumigatus is as a pathogen that causes invasive aspergillosis, a serious fungal infection. 2 2
From the Research
Role of Aspergillus fumigatus
- Aspergillus fumigatus is a filamentous fungus that can infect the lungs of patients with immunosuppression and/or underlying lung diseases 3.
- It is an opportunistic pathogen that poses a serious health threat to humans, especially in immunocompromised patients, causing numerous invasive infections and a notable mortality rate 4.
- The fungus can cause various clinical syndromes, including aspergilloma, allergic bronchopulmonary aspergillosis, and invasive aspergillosis, which can be severe and usually fatal 5.
Pathogenesis and Immune Response
- The innate immune response to A. fumigatus is stage-specific, and various components of the host's defenses are recruited to challenge the different cellular forms of the pathogen 6.
- In immunocompetent hosts, anatomical barriers and professional phagocytes such as alveolar macrophages and neutrophils prevent the development of aspergillosis by inhibiting the growth of conidia and hyphae 6.
- Recent advances in understanding the pathogenesis of invasive aspergillosis have highlighted the multifactorial nature of A. fumigatus virulence and the complex interplay between host and microbial factors 7.
Clinical Challenges and Treatment
- The global emergence of azole-resistant A. fumigatus isolates in clinic and environment limits the therapeutic options of mould-active antifungals and potentially can be attributed to a high mortality rate 4.
- Treatment failure is also common in patients infected with azole-susceptible isolates, which can be due to several non-mutually exclusive reasons, such as poor drug absorption, tolerance, or persistence 3.
- The phenomena of antibacterial tolerance and persistence have received significant attention, and their relevance for treatment failure in bacterial infections has been demonstrated, but the knowledge of antifungal tolerance and persistence is still limited 3.