Browsing by Author "Martins, Carlos"
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- Aspergillus em ambiente hospitalar: um risco para o desenvolvimento de infeções nosocomiais?Publication . Raquel, Sabino; Veríssimo, Cristina; Viegas, Carla; Brandão, João; Parada, Helena; Martins, Carlos; Furtado, Cristina; Clemons, Karl V.; Stevens, David A.
- Aspergillus nosocomial infections Do cryptic species found in hospital environment matter?Publication . Sabino, Raquel; Viegas, C.; Francisco, M.; Martins, Carlos; Clemons, Karl; Stevens, DavidPurpose: Aspergillus is a major threat causing nosocomial infections in immunocompromised patients. Advances in molecular methods allowed species identification through sequencing of specific genes, allowing high discrimination amongst isolates. Different Aspergillus species have different susceptibilities to antifungals and several cryptic species have been described as less susceptible to specific antifungals. Therefore, we addressed the possible influence of hospital environmental isolates in the overall situation of Aspergillus antifungal resistance. Methods: During one year, 101 air and 99 surface samples were collected from the environment of a Portuguese central hospital of Lisbon. Aspergillus isolates were identified morphologically and by molecular methods. Genomic DNA was prepared from each isolate and then sequenced to achieve the correct species identification. Determination of the antifungal susceptibility of selected isolates was performed by microdilution (CLSI M38-A2). The antifungal agents studied were deoxycholate amphotericin B, itraconazole, voriconazole, and posaconazole. Results: From the 200 samples collected, 75 isolates of Aspergillus were obtained and identified to section by ITS sequence; cryptic species were identified by β-tubulin and calmodulin sequencing. Ten different sections within the Aspergillus genus were identified: Versicolores (N=20), Nigri (N=11), Flavi (N=10), Circumdati (N=10), Fumigati (N=8), Usti (N=4), Terrei (N=4), Nidulantes (N=4), Aspergilli (N=3) and Cremei (N=1). From these, 25 different Aspergillus species were identified by β-tubulin and calmodulin sequencing, and a high percentage of cryptic species (not sensu stricto) was found (59%). Sections Usti, Versicolores and Circumdati harbored the highest proportion of cryptic species [100% (4/4), 95% (19/20) and 90% (9/10), respectively]. From the 75 isolates, 22 were tested for their antifungal susceptibility. Of the 8 Fumigati isolates, there was 1 cryptic species. The Circumdati, Versicolores and Nigri complexes contained isolates of cryptic species with reduced susceptibility to some of the antifungals used in clinical therapeutics. In the Circumdati complex, 3/5 isolates hadMIC to amphotericin B >8μg/ml and 1/5MIC >8μg/ml to itraconazole; 1/6 isolates fromVersicolores complex hadMIC to itraconazole >8 μg/ml; all 4 isolates fromNigri complex hadMIC to itraconazole=4 μg/ml. Conclusion: Since Aspergillus infections aremainly nosocomial, knowledge of themolecular epidemiology and determinationof the susceptibility profile of environmental isolateswould suggestmeasures need to be considered.
- Comparison between influenza coded primary care consultations and national influenza incidence obtained by the General Practitioners Sentinel Network in Portugal from 2012 to 2017Publication . Páscoa, Rosália; Rodrigues, Ana Paula; Silva, Susana; Nunes, Baltazar; Martins, CarlosInfluenza is associated with severe illness, death, and economic burden. Sentinel surveillance systems have a central role in the community since they support public health interventions. This study aimed to describe and compare the influenza-coded primary care consultations with the reference index of influenza activity used in Portugal, General Practitioners Sentinel Network, from 2012 to 2017. An ecological time-series study was conducted using weekly R80-coded primary care consultations (according to the International Classification of Primary Care-2), weekly influenza-like illness (ILI) incidence rates from the General Practitioners Sentinel Network and Goldstein Index (GI). Good accordance between these three indicators was observed in the characterization of influenza activity regarding to start and length of the epidemic period, intensity of influenza activity, and influenza peak. A high correlation (>0.75) was obtained between weekly ILI incidence rates and weekly number of R80-coded primary care consultations during all five studied seasons. In 3 out of 5 seasons this correlation increased when weekly ILI incidence rates were multiplied for the percentage of influenza positive cases. A cross-correlation between weekly ILI incidence rates and the weekly number of R80-coded primary care consultations revealed that there was no lag between the rate curves of influenza incidence and the number of consultations in the 2012/13 and 2013/14 seasons. In the last three seasons, the weekly influenza incidence rates detected the influenza epidemic peak for about a week earlier. In the last season, the GI anticipated the detection of influenza peak for about a two-week period. Sentinel networks are fundamental elements in influenza surveillance that integrate clinical and virological data but often lack representativeness and are not able to provide regional and age groups estimates. Given the good correlation between weekly ILI incidence rate and weekly number of R80 consultations, primary care consultation coding system may be used to complement influenza surveillance data, namely, to monitor regional influenza activity. In the future, it would be interesting to analyse concurrent implementation of both surveillance systems with the integration of all available information.
- Infecção fúngica em Portugal - o gigante adormecidoPublication . Sabino, Raquel; Veríssimo, Cristina; Martins, Carlos; Brandão, JoãoA Micologia clínica é tradicionalmente reconhecida como sendo de pouca expressão em contexto não imunocomprometido, sendo as infeções fúngicas associadas principalmente a doentes com imunodeficiência adquirida, diabetes, cancro, fibrose quística, queimados e pouco mais. Mas será verdadeiramente assim? Este artigo faz uma actualização sobre a infecção fúngica em Portugal, contextualizando-a no mundo atual, perspetivando resistências terapêuticas e prevenção.
- Trends on Aspergillus Epidemiology-Perspectives from a National Reference Laboratory Surveillance ProgramPublication . Sabino, Raquel; Gonçalves, Paulo; Martins Melo, Aryse; Simões, Daniela; Oliveira, Mariana; Francisco, Mariana; Viegas, Carla; Carvalho, Dinah; Martins, Carlos; Ferreira, Teresa; Toscano, Cristina; Simões, Helena; Veríssimo, CristinaIdentification of Aspergillus to species level is important since sibling species may display variable susceptibilities to multiple antifungal drugs and also because correct identification contributes to improve the knowledge of epidemiological studies. Two retrospective laboratory studies were conducted on Aspergillus surveillance at the Portuguese National Mycology Reference Laboratory. The first, covering the period 2017-2018, aimed to study the molecular epidemiology of 256 Aspergillus isolates obtained from patients with respiratory, subcutaneous, or systemic infections and from environmental samples. The second, using our entire collection of clinical and environmental A. fumigatus isolates (N = 337), collected between 2012 and 2019, aimed to determine the frequency of azole-resistant A. fumigatus isolates. Aspergillus fumigatus sensu stricto was the most frequent species in both clinical and environmental samples. Overall, and considering all Aspergillus sections identified, a high frequency of cryptic species was detected, based on beta-tubulin or calmodulin sequencing (37% in clinical and 51% in environmental isolates). Regarding all Fumigati isolates recovered from 2012-2019, the frequency of cryptic species was 5.3% (18/337), with the identification of A. felis (complex), A. lentulus, A. udagawae, A. hiratsukae, and A. oerlinghauensis. To determine the frequency of azole resistance of A. fumigatus, isolates were screened for azole resistance using azole-agars, and 53 possible resistant isolates were tested by the CLSI microdilution reference method. Nine A. fumigatus sensu stricto and six Fumigati cryptic isolates showed high minimal inhibitory concentrations to itraconazole, voriconazole, and/or posaconazole. Real-time PCR to detect cyp51A mutations and sequencing of cyp51A gene and its promoter were performed. The overall frequency of resistance to azoles in A. fumigatus sensu stricto was 3.0%. With this retrospective analysis, we were able to detect one azole-resistant G54R mutant A. fumigatus environmental isolate, collected in 2015. The TR34/L98H mutation, linked to environmental transmission route of azole resistance, was the most frequently detected mutation (N = 4; 1.4%). Our findings underline the demand for correct identification and susceptibility testing of Aspergillus isolates.