Aspergillus-related lung disease in people with cystic fibrosis: can imaging help us to diagnose disease?

Epidemiology of Clinically Significant Aspergillus Species from a Large Tertiary Hospital in Shanghai, China, for the Period of Two Years

Background

Aspergillus species are becoming a major public health concern worldwide due to the increase in the incidence of aspergillosis and emergence of antifungal resistance. In this study, we surveyed all Aspergillus species isolated from aspergillosis patients in Zhongshan Hospital Fudan University, Shanghai, China, from 2019 to 2021.

Methods

We characterized the susceptibility profiles of these Aspergillus species to medical azoles (voriconazole, itraconazole and posaconazole) using YeastOne^TM broth microdilution system. To determine the underlying antifungal resistance mechanisms in azole-resistant A. fumigatus (ARAf) isolates, we characterized mutations in the cyp51A gene. Genotypic diversity of sampled A. fumigatus was investigated using CSP-typing.

Results

A total of 112 Aspergillus isolates (81 A. fumigatus, 17 A. flavus, 5 A. niger, 2 A. terreus, 2 A. lentulus, 2 A. oryzae, 1 A. nidulans, 1 A. versicolor and 1 A. sydowii) from 105 patients diagnosed with aspergillosis (including proven or probable invasive aspergillosis, chronic pulmonary aspergillosis, allergic bronchopulmonary aspergillosis and cutaneous aspergillosis) were obtained. Eight isolates (7 A. fumigatus and 1 A. niger) from seven patients were either azole non-susceptible or non-wild type. Azole non-susceptible or non-wild type rate was 7.1%/isolate and 6.7%/patient analysed. Four ARAf harbored TR34/L98H mutation, whereas one carried TR46/Y121F/T289A allele. The 81 A. fumigatus isolates were spread across 8 CSP types with t01 to be the predominant type (53.1%). ARAf isolates were distributed over CSP types t01, t02, t04A and t11.

Conclusion

Results from this study provided us with an understanding of the antifungal resistance and related characteristics of Aspergillus species in Eastern China. Further comparisons of our results with those in other countries reflect potential clonal expansion of A. fumigatus in our region. Further surveillance study is warranted to guide antifungal therapy and for epidemiological purposes.

A case-control study of the effects of Aspergillus clinical phenotypes on pulmonary functions in patients with cystic fibrosis

INTRODUCTION

There are no precise data about the effect of Aspergillus infection on lung function other than allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis (pwCF). Here, we aimed to determine clinical phenotypes caused by Aspergillus spp. using laboratory and immunologic parameters and to compare Aspergillus phenotypes in terms of pulmonary function tests (PFT) prospectively.

METHODS

Twenty-three pwCF who had Aspergillus isolation from respiratory cultures in the last year (case group) and 20 pwCF without Aspergillus isolation in sputum (control group) were included. Aspergillus immunoglobulin (Ig)-G, Aspergillus IgE, Aspergillus polymerase chain reaction (PCR), galactomannan, total IgE from blood samples, and Aspergillus PCR and galactomannan from sputum, and skin prick test reactivity to Aspergillus antigen were used to distinguish different Aspergillus phenotypes. Pulmonary functions and frequency of pulmonary exacerbations were evaluated during a 1-year follow-up.

RESULTS

Of 23 pwCF, 11 (47.8%) had Aspergillus colonization, nine (39.1%) had Aspergillus bronchitis, and three (13%) had ABPA. Aspergillus infection was not associated with worse z-scores of forced expiratory volume in the first second (FEV1) (p = 0.612), forced vital capacity  (p = 0.939), and the median FEV 1% decline (0.0%/year vs. -4.7%/year, p = 0.626). The frequency of pulmonary exacerbations in the Aspergillus infected and noninfected groups was similar.

CONCLUSION

Although Aspergillus spp. Isolation in pwCF was not associated with decreased lung function, a further decline was seen in the ABPA subgroup, and frequent pulmonary exacerbations during the 1-year follow-up.

Specific Focus on Antifungal Peptides against Azole Resistant Aspergillus fumigatus: Current Status, Challenges, and Future Perspectives

The prevalence of fungal infections is increasing worldwide, especially that of aspergillosis, which previously only affected people with immunosuppression. Aspergillus fumigatus can cause allergic bronchopulmonary aspergillosis and endangers public health due to resistance to azole-type antimycotics such as fluconazole. Antifungal peptides are viable alternatives that combat infection by forming pores in membranes through electrostatic interactions with the phospholipids as well as cell death to peptides that inhibit protein synthesis and inhibit cell replication. Engineering antifungal peptides with nanotechnology can enhance the efficacy of these therapeutics at lower doses and reduce immune responses. This manuscript explains how antifungal peptides combat antifungal-resistant aspergillosis and also how rational peptide design with nanotechnology and artificial intelligence can engineer peptides to be a feasible antifungal alternative.

Suppression of Aspergillus fumigatus Germination by Neutrophils Is Enhanced by Endothelial-Derived CSF3 Production

Infection with Aspergillus fumigatus can cause life-threatening diseases in immunocompromised patients with an unacceptable mortality rate. Angioinvasion is one of the features of severe invasive aspergillosis. Neutrophils are short-lived immune cells regulated by colony-stimulating factor 3 (CSF3) that play a key role in anti-fungal immune responses. To investigate the interactions between A. fumigatus and the host immune cells, such as neutrophils, we stimulated human umbilical vein endothelial cells (HUVECs) with the conidia of A. fumigatus, and co-cultured them with human neutrophils. Apoptosis and functions of neutrophils were analyzed. Our results showed that HUVECs upregulate the expression of CSF3, which could reduce the apoptosis of neutrophils while enhancing their functions. Lack of CSF3 was associated with enhanced apoptosis of neutrophils with impaired function. This work indicated that the CSF3 is required for neutrophil survival and function, at least in the early stages of A. fumigatus infection.

Clinical Impact of Aspergillus fumigatus in Children with Cystic Fibrosis

Background. The clinical relevance of Aspergillus fumigatus (Af) in cystic fibrosis (CF) is controversial. The aims of the study were to assess the prevalence of Af disease in our cohort of CF patients and evaluate whether allergic bronchopulmonary aspergillosis (ABPA) and sensitization to Af affected lung function, body mass index (BMI) and exacerbations. Methods. Clinical data and lung function of CF patients aged 6−18 years followed at the CF Centre of Parma (Italy) were recorded. Patients were classified as: patients with no signs of Af, patients sensitized or colonized by Af, patients with ABPA or patients with Aspergillus bronchitis (Ab). Results. Of 38 CF patients (14.2 years (6.2−18.8) M 23), 8 (21%) showed Af sensitization, 7 (18.4%) showed ABPA, 1 (2.6%) showed Af colonization and 1 (2.6%) showed Ab. Compared to non-ABPA, patients with ABPA had lower BMI (15.9 ± 1.6 vs. 19.7 ± 3.4, p < 0.005), lower lung function (FEV1 61.5 ± 25.9% vs. 92.3 ± 19.3%, p < 0.001) and more exacerbations/year (4.43 ± 2.44 vs. 1.74 ± 2.33, p < 0.005). Patients with Af sensitization showed more exacerbations/year than non-Af patients (3.5 ± 3.2 vs. 0.9 ± 1.2, p < 0.005). ABPA and sensitized patients had more abnormalities on chest CT scans. Conclusion. This study showed the relevant clinical impact of ABPA and Af sensitization in terms of exacerbations and lung structural damage.