Browsing by Author "Almeida, Beatriz"
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- Algorithm to assess the presence of Aspergillus fumigatus resistant strains: The case of Norwegian sawmillsPublication . Viegas, Carla; Almeida, Beatriz; Aranha Caetano, Liliana; Afanou, Anani; Straumfors, Anne; Veríssimo, Cristina; Gonçalves, Paulo; Sabino, RaquelAssociation between selection pressure caused by the use of azole fungicides in sawmills and the development of fungal resistance has been described. The aim of this study was to implement an algorithm to assess the presence of Aspergillus section Fumigati resistant strains in sawmills. Eighty-six full-shift inhalable dust samples were collected from eleven industrial sawmills in Norway. Different culture media were used and molecular identification to species level in Aspergillus section Fumigati was done by calmodulin sequencing and TR34/L98H and TR46/Y121F/T289A mutations were screened by real-time PCR assay and confirmed by cyp51A sequencing. Six Fumigati isolates were identified as A. fumigatus sensu stricto and two of these grew on azole-supplemented media and were further analyzed by real-time PCR. One was confirmed to be a TR34/L98H mutant. The obtained results reinforce the need to assess the presence of A. fumigatus sensu stricto resistant isolates at other workplaces with fungicide pressure.
- Algorithm to assess the presence of Aspergillus fumigatus resistant strains: The case of Norwegian sawmillsPublication . Viegas, Carla; Almeida, Beatriz; Aranha Caetano, Liliana; Afanou, Anani; Straumfors, Anne; Veríssimo, Cristina; Gonçalves, Paulo; Sabino, RaquelAssociation between selection pressure caused by the use of azole fungicides in sawmills and the development of fungal resistance has been described. The aim of this study was to implement an algorithm to assess the presence of Aspergillus section Fumigati resistant strains in sawmills. Eighty-six full-shift inhalable dust samples were collected from eleven industrial sawmills in Norway. Different culture media were used and molecular identification to species level in Aspergillus section Fumigati was done by calmodulin sequencing and TR34/L98H and TR46/Y121F/T289A mutations were screened by real-time PCR assay and confirmed by cyp51A sequencing. Six Fumigati isolates were identified as A. fumigatus sensu stricto and two of these grew on azole-supplemented media and were further analyzed by real-time PCR. One was confirmed to be a TR34/L98H mutant. The obtained results reinforce the need to assess the presence of A. fumigatus sensu stricto resistant isolates at other workplaces with fungicide pressure.
- Aspergillus spp. and azole-resistance characterization on Filtering Respiratory Protective Devices from waste sorting industryPublication . Viegas, Carla; Dias, Marta; Almeida, Beatriz; Gonçalves, Paulo; Veríssimo, Cristina; Sabino, Raquel; Aranha Caetano, LilianaStudies performed on waste management industry have reported Aspergillus as the most frequent genera on waste-sorting, incineration and composting. Filtering Respiratory Protective Devices (FRPD) are disposable after one-day use (workshift) and their use is mandatory in Portuguese waste-sorting industries. During FRPD use, humidity and temperature conditions provide a favorable environment for the growth of retained Aspergillus. The aim of this study was to characterize Aspergillus spp. presence in FRPD interior layer and exhalation valves, as well as to detect possible azole-resistant isolates in this complex indoor environment. Methods The analyzed samples consisted of 120 FRPD (interior layer and exhalation valves). Fungal load was extracted from both matrixes with 10 mL of 0.1% Tween™ 80 saline solution (NaCl 0.9%) for 30 min at 250 rpm, and 150 μL of those extracts were streaked onto malt extract agar (MEA) supplemented with chloramphenicol (0.05%) and dichloran glycerol agar (DG18). After incubation at 27 ºC for 5 to 7 days Aspergillus spp. densities (CFU/m2) were calculated, and Aspergillus sections were identified through macro and microscopic characteristics. The frequency of azole-resistance was determined by inoculation of the extracts onto screening agar plates containing Sabouraud dextrose agar media supplemented with 4 mg/L itraconazole (ITRA), 1 mg/L voriconazole (VORI), and 0.5 mg/L posaconazole (POSA), incubated at 27 °C for 5 days. Results Aspergillus spp. was detected in both interior layers (77 out of 120; 64.17%) and exhalation valves (63 out of 120; 52.5%). Among the Aspergillus genera, section Fumigati presented the highest frequency, both in exhalation valves (76.57% MEA; 87.24% DG18) and in interior layers (75.81% MEA; 51.22% DG18). Fumigati and Nigri were the Aspergillus sections isolated more frequently on MEA. In addition, Flavi, Circumdati and Candidi sections were also frequently isolated on DG18. Restricti and Aspergilli sections were observed occasionally. DG18 allowed the detection of a more diversified set of Aspergillus species than MEA (in both FRPD matrixes). In azole-supplemented media, Aspergillus spp. was the most frequently found genus on exhalation valves (75.0% of the isolates that grew onto ITRA), suggesting that resistant isolates to ITRA at the tested concentration might be present in this occupational environment. Conclusions This study reports contamination of FRPD used by workers at waste industry with Aspergillus and Aspergillus isolates exhibiting reduced susceptibility to azoles. Future trials should be performed to test the protective efficacy of FRPD and to establish deadlines for FRPD replacement. Monitoring of the establishment of azole-resistant strains in this work environment should be continued to reduce the risk of exposure and consequent development of fungal infections.
- Azole-Resistant Aspergillus fumigatus Harboring the TR34/L98H Mutation: First Report in Portugal in Environmental SamplesPublication . Gonçalves, Paulo; Melo, Aryse; Dias, Marta; Almeida, Beatriz; Caetano, Liliana Aranha; Veríssimo, Cristina; Viegas, Carla; Sabino, RaquelIntroduction: The frequency in detection of azole-resistant Aspergillus fumigatus isolates has increased since 2010. In Portugal, the section Fumigati is one of the most frequent, and resistant strains to have been found in clinical and environmental contexts. Although several cryptic species within the Fumigati section show intrinsic resistance to azoles, one factor driving (acquired) resistance is selective pressure deriving from the extensive use of azoles. This is particularly problematic in occupational environments where high fungal loads are expected, and where there is an increased risk of human exposure and infection, with impact on treatment success and disease outcome. The mechanisms of resistance are diverse, but mainly associated with mutations in the cyp51A gene. Despite TR34/L98H being the most frequent mutation described, it has only been detected in clinical specimens in Portugal. Methods: We analyzed 99 A. fumigatus isolates from indoor environments (healthcare facilities, spas, one dairy and one waste sorting unit) collected from January 2018 to February 2019 in different regions of Portugal. Isolates were screened for resistance to itraconazole, voriconazole and posaconazole by culture, and resistance was confirmed by broth microdilution. Sequencing of the cyp51A gene and its promoter was performed to detect mutations associated with resistance. Results: Overall, 8.1% of isolates were able to grow in the presence of at least one azole, and 3% (isolated from the air in a dairy and from filtering respiratory protective devices in a waste sorting industry) were pan-azole-resistant, bearing the TR34/L98H mutation. Conclusion: For the first time in Portugal, we report environmental isolates bearing the TR34/L98H mutation, isolated from occupational environments. Environmental surveillance of the emergence of azole-resistant A. fumigatus sensu stricto strains is needed, to ensure proper and timely implementation of control policies that may have a positive impact on public and occupational health.
- Exposure assessment in one central hospital: A multi-approach protocol to achieve an accurate risk characterizationPublication . Viegas, Carla; Almeida, Beatriz; Monteiro, Ana; Paciência, Inês; Rufo, João; Aguiar, Lívia; Lage, Bruna; Diogo Gonçalves, Lídia Maria; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Teixeira, João Paulo; Viegas, Susana; Pereira, CristianaThe bioburden in a Hospital building originates not only from patients, visitors and staff, but is also disseminated by several indoor hospital characteristics and outdoor environmental sources. This study intends to assess the exposure to bioburden in one central Hospital with a multi-approach protocol using active and passive sampling methods. The microbial contamination was also characterized through molecular tools for toxigenic species, antifungal resistance and mycotoxins and endotoxins profile. Two cytotoxicity assays (MTT and resazurin) were conducted with two cell lines (Calu-3 and THP-1), and in vitro pro-inflammatory potential was assessed in THP-1 cell line. Out of the 15 sampling locations 33.3% did not comply with Portuguese legislation regarding bacterial contamination, whereas concerning fungal contamination 60% presented I/O > 1. Toxigenic fungal species were observed in 27% of the sampled rooms (4 out of 15) and qPCR analysis successfully amplified DNA from the Aspergillus sections Flavi and Fumigati, although mycotoxins were not detected. Growth of distinct fungal species was observed on Sabouraud dextrose agar with triazole drugs, such as Aspergillus section Versicolores on 1 mg/L VORI. The highest concentrations of endotoxins were found in settled dust samples and ranged from 5.72 to 23.0 EU.mg-1. While a considerable cytotoxic effect (cell viability < 30%) was observed in one HVAC filter sample with Calu-3 cell line, it was not observed with THP-1 cell line. In air samples a medium cytotoxic effect (61-68% cell viability) was observed in 3 out of 15 samples. The cytokine responses produced a more potent average cell response (46.8 ± 12.3 ρg/mL IL-1β; 90.8 ± 58.5 ρg/mL TNF-α) on passive samples than air samples (25.5 ± 5.2 ρg/mL IL-1β and of 19.4 ± 5.2 ρg/mL TNF-α). A multi-approach regarding parameters to assess, sampling and analysis methods should be followed to characterize the biorburden in the Hospital indoor environment. This study supports the importance of considering exposure to complex mixtures in indoor environments.