Aspergillus fumigatus-Related Species in Clinical Practice

Abstract

Aspergillus fumigatus is the main etiologic agent of invasive aspergillosis (IA). Other Aspergillus species belonging to the section Fumigati (A. fumigatus complex) may occasionally be the cause of IA. These strains are often misidentified, as they cannot be distinguished from A. fumigatus by conventional morphological analysis and sequencing methods. This lack of recognition may have important consequences as these A. fumigatus-related species often display some level of intrinsic resistance to azoles and other antifungal drugs. A. lentulus, A. udagawae, A. viridinutans, and A. thermomutatus (Neosartorya pseudofischeri) have been associated with refractory cases of IA. Microbiologists should be able to suspect the presence of these cryptic species behind a putative A. fumigatus isolate on the basis of some simple characteristics, such as defect in sporulation and/or unusual antifungal susceptibility profile. However, definitive species identification requires specific sequencing analyses of the beta-tubulin or calmodulin genes, which are not available in most laboratories. Multiplex PCR assays or matrix-assisted laser desorption ionization – time-of-flight mass spectrometry (MALDI-TOF MS) gave promising results for rapid and accurate distinction between A. fumigatus and other Aspergillus spp. of the section Fumigati in clinical practice. Improved diagnostic procedures and antifungal susceptibility testing may be helpful for the early detection and management of these particular IA cases.

Azole-resistantAspergillus fumigatusin sawmills of Eastern France

“…This finding illustrates the importance of molecular biology techniques to correctly identify the Aspergillus species of the section Fumigati, notably when the species involved are naturally resistant to azole antifungals and can be misidentified as A. fumigatus (i.e. A. lentulus) (Lamoth 2016). Although A. oerlinghausenensis has not been involved in IA in human until now, its pathogenicity requires further explorations because of its substantial presence in the environment and its resistance profile.…”

Invasive Aspergillosis in Transplant Recipients

“…The most common etiological agent of invasive aspergillosis with a high morality is A. fumigatus, responsible for the majority (up to 90%) of cases in humans [1,12,[15][16][17][18][19]. It is followed by A. flavus, which causes up to 10% of cases of…”

“…Molds of the genus Aspergillus may cause a wide variety of clinical entities, ranging from asymptomatic colonization, allergic bronchopulmonary aspergillosis, and chronic pulmonary aspergillosis to severe (even fulminant) invasive infections in almost every organ or system in the body of the host, including (but not limited to) the lungs, heart, central nervous system, and the sinuses [5,18,19,24]. The most common clinical form of invasive diseases caused by Aspergillus spp.…”

“…Paranasal sinuses may be colonized or infected by fungi, while infection can be invasive (acute or chronic) or noninvasive (allergic sinusitis and aspergilloma) [18]. In invasive aspergillosis of the sinuses, there are rapid (within a few days) destructions of the sinuses, the nasal cavity, and the adjacent structures, such as the orbit and the brain [18]. Aspergillus spp.…”

Diversity of Azoles Resistant Aspergillus Species Isolated from Experience and Naïve Soils in Nairobi County and Naivasha Sub-County Kenya

“…In contrast Netherland surveillance studies showed that azole resistance is endemic, TR46/Y121F/T289A and TR34/L98H cyp51A gene mediated resistance been the most common (Van der Linden et al, 2011).Multicenter international surveillance network study reported 3.2% triazoles resistance. Majority of resistant isolates were Aspergillus species at 78% and 22% of the other sibling species (A. lentulus, A. udagawae and A. thermomutatus) (Lamoth, 2016, Van der Linden et al, 2015.…”