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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Ocorrência de Aspergilose pulmonar em cães com sintomatologia respiratória atendidos no HCV- UFRGS, Porto Alegre

Teixeira, Fábio dos Santos January 2012 (has links)
A pneumonia fúngica é uma infecção pulmonar profunda causada principalmente por fungos do gênero Aspergillus, incluindo A. fumigatus, A. niger, A. flavus e A. terreus. Se encontram mais comumente em matéria orgânica em decomposição. Seus propágulos estão presentes na poeira e no ar, o que favorece a inalação, porta principal de entrada do agente no organismo. Produzem grande quantidade de conídios com menos de 8 μ, fazendo com que, quando inalados, alcancem o leito pulmonar. É o gênero considerado o mais comum em nosso planeta e o A. fumigatus é a espécie mais frequentemente descrita em invasão tecidual. Em animais e humanos, os sistemas respiratório e imunológico saudáveis são suficientes para eliminar os propágulos das vias aéreas, evitando sua colonização. Doenças e fármacos imunossupressores têm sido descritos como fatores predisponentes da infecção pulmonar fúngica, considerada oportunística. É considerada rara em cães. Os sinais clínicos são variados, mas a tosse persistente e a não cessação dos sinais com o uso de antimicrobianos são dados para suspeita de pneumonia fúngica. No exame radiológico de pulmões, são descritas várias imagens, das quais a mais relatada é a de padrão intersticial nodular miliar generalizado, embora não seja imagem patognomônica. Este trabalho teve como objetivo verificar a ocorrência de aspergilose pulmonar em cães com sintomatologia respiratória atendidos no Hospital de Clínicas Veterinárias da Universidade Federal do Rio Grande do Sul (HCV-UFRGS), localizado na cidade de Porto Alegre. A amostragem foi composta por 46 cães nos quais foi realizado Biópsia por Aspiração com Agulha Fina (BAAF) nos dois pulmões, coleta de sangue e exame radiológico torácico. O material obtido de uma punção foi homogeneizado com caldo Sabouraud Dextrose líquido. Parte deste homogeneizado foi semeado em Agar Malte para Aspergillus spp. e feito exame direto em lâmina e com colotração de Grocott. A outra parte foi semeada em vários meios de cultura para exame bacteriológico. Do material obtido na outra punção foi realizado exame citopatológico corado pelo método Panótico Rápido. Do soro obtido do sangue coletado foi realizado exame soromicológico para A. fumigatus, A. flavus e A. niger. Os resultados dos exames micológico, citopatológico, soromicológico e bacteriológico foram negativos para todas as amostras testadas. Não havendo positividade dos exames, não foi possível correlacionar a pneumonia fúngica com as imagens radiológicas obtidas dos pulmões dos 46 cães radiografados. A maioria dos cães viviam em áreas abertas, em contato com matéria orgânica onde o fungo frequentemente se encontra. Os exames para detecção de fungos devem ser analisados com cautela, pois o resultado positivo em um único exame não confirma a presença da infecção, pois o agente pode estar presente frequentemente no trato respiratório superior de cães. / Fungal pneumonia is a deeply lung infection caused by fungal agents of the genus Aspergillus, including A. fumigatus, A. niger, A. flavus and A. terreus. They are found most commonly in decaying organic matter. Their fungal propagules are present in dust and air, which favors the inhalation, the main entrance of the agent in the body. They produce large amounts of conidia with less than 8 μ, so that, when inhaled, reaching the pulmonary bed. It is the considered the most common kind genus on our planet and A. fumigatus is the most often reported species in tissue invasion. In animals and humans, a healthy immune and respiratory systems is sufficient to remove the seedlings of the airways, preventing colonization. Diseases and immunosuppressive drugs have been described as predisposing factors of pulmonary fungal infection, considered opportunistic. It is considered rare in dogs. Clinical symptoms are varied, but a persistent cough and no cessation of symptoms with the use of antimicrobials are data for suspected fungal pneumonia. In the radiological examination of the lungs, several images have been described, and the most described is a generalized miliary nodular interstitial pattern, but it is not a pathognomonic image. This work aimed to verify the occurrence of pulmonary aspergillosis in dogs with respiratory symptoms examined at the Veterinary Clinical Hospital of Federal University of Rio Grande do Sul (HCVUFRGS), located in Porto Alegre city, in Brasil. The sampling was composed of 46 dogs in which biopsy was performed by fine needle aspiration (FNAC) in both lungs, blood sampling and radiological examination of the chest. The material obtained from a puncture was homogenized with Sabouraud dextrose liquid. Part of this homogenate was seeded on malt agar for Aspergillus spp. and taken directly on slides and stained with “Grocott”. The other party was seeded in various culture media to bacteriological examination. The material obtained in another puncture was performed cytopathological examination with “Panótico” coloring. Serum obtained from blood collected was performed for serology to A. fumigatus, A. flavus and A. niger. The results of mycological examination, cytology, bacteriology and serology examinations were negative for all samples tested. In the absence of positive tests, it was not possible to correlate fungal pneumonia with radiological images obtained from the lungs of the 46 dogs radiographed. Most dogs live in open areas in contact with organic matter where the fungus is usually found. Tests to detect fungi should be analyzed with caution, because a positive result in a single test does not confirm the presence of infection, since the agent can be present normally in the upper respiratory tract of dogs.
12

Achados na tomografia computadorizada de alta resolução da aspergilose pulmonar em pacientes transplantados de pulmão

Gazzoni, Fernando Ferreira January 2014 (has links)
O objetivo deste estudo foi avaliar os achados na tomografia computadorizada de alta resolução (TCAR) de pacientes transplantados de pulmão diagnosticados com infecção pulmonar por Aspergillus. Foram revisados retrospectivamente os exames de TCAR de 23 pacientes diagnosticados com aspergilose. Os exames de imagem foram realizados entre 2-5 dias após o início dos sintomas. A amostra de pacientes incluiu 12 homens e 11 mulheres com idades entre 22-59 anos (idade média: 43,6 anos). Todos os pacientes apresentaram taquipnéia, dispnéia e tosse. O diagnóstico foi estabelecido com o ensaio imunoenzimático (Platelia Aspergillus) para a detecção do antígeno galactomanana no lavado broncoalveolar e recuperação dos sintomas e dos achados de TCAR após tratamento com voriconazol. As TCAR foram analisadas independentemente por dois observadores que chegaram a uma decisão em consenso. O principal padrão na TCAR encontrado foi o de nódulos centrolobulares com padrão de árvore-em-brotamento associados com espessamento de paredes brônquicas que foi visualizado em 65% (n=15) dos pacientes. Este padrão foi descrito em associação com áreas de consolidação e opacidades em vidro-fosco em 13% (n=3) dos pacientes. Consolidação e opacidades em vidro-fosco foi o padrão principal em 22% (n=5) dos pacientes. O padrão de nódulos grandes com e sem o sinal do halo foi observado em 13% (n=3) dos pacientes e, em um caso, esteve associado com consolidação e opacidades em vidro-fosco. Conclui-se que os achados predominantes na TCAR em pacientes transplantados de pulmão com aspergilose foram espessamento de paredes brônquicas e opacidades centrolobulares com padrão de árvore-em-brotamento bilateralmente. Além disso, opacidades em vidro-fosco e / ou áreas de consolidação bilaterais foram achados comuns. Os nódulos com o sinal do halo foram encontrados em apenas 13% dos pacientes. / The aim of this study was to assess high-resolution computed tomographic (HRCT) findings at presentation in lung transplant patients diagnosed with pulmonary Aspergillus infection. We retrospectively reviewed HRCT findings from 23 patients diagnosed with pulmonary aspergillosis. Imaging studies were performed 2–5 days after the onset of symptoms. The patient sample comprised 12 men and 11 women aged 22–59 years (mean age, 43.6 years). All patients had dyspnea, tachypnea, and cough. Diagnoses were established with Platelia Aspergillus enzyme immunoassays for galactomannan antigen detection in bronchoalveolar lavage and recovery of symptoms, and HRCT findings after voriconazole treatment. The HRCT scans were reviewed independently by two observers who reached a consensus decision. The main HRCT pattern, found in 65% (n = 15) of patients, was centrilobular tree-in-bud nodules associated with bronchial thickening. This pattern was described in association with areas of consolidation and ground-glass opacities in 13% (n = 3) of patients. Consolidation and ground-glass opacities were the main pattern in 22% (n = 5) of patients. The pattern of large nodules with and without the halo sign was observed in 13% (n = 3) of patients, and were associated with consolidation and ground-glass opacities in one case. In conclusion, the predominant HRCT findings in lung transplant patients with pulmonary aspergillosis were bilateral bronchial wall thickening and centrilobular opacities with the tree-in-bud pattern. Ground-glass opacities and/or bilateral areas of consolidation were also common findings. Pulmonary nodules with the halo sign were found in only 13% of patients.
13

Développement et caractérisation physico-chimique d'une nouvelle forme galénique à base d'Amphotéricine B adaptée à la voie orale et pulmonaire / Development and physicochemical characterization of a new galenic form based on Amphotericin B adapted to the oral and pulmonary route

Mehenni, Lyes 07 March 2018 (has links)
Les infections fongiques peuvent s’exprimer sous différentes formes (leishmaniose cutanée ouviscérale, aspergillose pulmonaire à caractère allergique ou invasive) et connaissent unerecrudescence dans les pays développés en affectant principalement les personnesimmunodéprimées comme les cancéreux, les malades ayant subis des greffes d’organes ou lespatients atteints du VIH. Ces infections sont une cause de mortalité chez 30% des sujetsatteints. L’approche médicamenteuse conventionnelle consiste en l’administration par voieintraveineuse (IV) d’antifongiques. L'Amphotéricine B (AmB), un antibiotiquede la familledes polyènes, reste à ce jour l'un des agents les plus efficaces dans le traitement des infectionsfongiques systémiques mais entraîne aussi des effets indésirables comme une néphrotoxicitéaigüe après injection. Pour améliorer l’index thérapeutique de cette molécule active, nousavons développé différents outils galéniques adaptés à d’autres voies d’administration. Dansun premier temps, nous avons mis au point des liposomes à base de céramides végétales,adaptés pour une administration orale et dans le but de traiter la leishmaniose viscérale. Cesliposomes ont été testés dans un modèle in vitro Estomac/Duodénum pour mimer lesconditions physiologiques et ont montré une bonne stabilité dans un tel milieu avec un tauxd’encapsulation satisfaisant. Des liposomes formulés à partir de Dimyristoylphosphatidylcholine(DMPC)/Dimyristoylphosphatidylglycérol (DMPG) et encapsulantl’AmB ont été étudiés à l’aide de la résonnance magnétique nucléaire (RMN31P et 1H) et parrésonnance paramagnétique électronique (RPE). Ces liposomes, dont la composition pourraitêtre adaptée pour une administration par voie pulmonaire, ont été utiliséscomme modèlemembranaire pour une étude des interactions du principe actif dans la matrice liposomale.Enfin, nous décrivons le développement et la caractérisation physico-chimique d’une nouvellegénération de dispersions solides amorphes sphériques formulées à base de polymères decyclodextrines très hydrophiles et d’amphotéricine B.Les formulations ont été obtenues sousforme de poudre sèche par spray-drying, une méthode de séchage par atomisation. Cessystèmes ont été caractérisés par diverses techniques : spectroscopie infrarouge à transforméede Fourier (FT-IR), spectroscopie Raman, granulométrie laser, microscopie électronique àtransmission et microscopie électronique à balayage. La distribution aérodynamique de cesdispersions solides amorphes a été évaluée à l’aide d’un impacteur à cascades afin de testerleur intérêt pour des applications potentielles par voie pulmonaire. / Résumé en anglais non disponible
14

ROC-Studie zur Bedeutung klinischer und radiologischer Befunde für die Diagnose von Patienten mit HIV-assoziierter invasiver Lungenaspergillose

Zaspel, Uta 16 October 2003 (has links)
Ziel: Die Studie zielte auf die Beurteilung von klinischer Information und Röntgenthorax jeweils alleine und in Kombination für Unterscheidung der invasiven pulmonalen Aspergillose von seinen pulmonalen Differentialdiagnosen. Design: Zur Evaluierung der diagnostischen Leistungen wurde eine Receiver Operating Characteristic Studie angewandt. Methodik: Die diagnostischen Leistungen der alleinigen Klinik, des alleinigen Röntgenthorax und der Kombination von Klinik und Röntgenthorax wurden ermittelt. An der Studie nahmen jeweils acht mit Aspergillose erfahrene Internisten und Radiologen teil. Dazu wurde eine aus 25 gesicherten Fällen mit Aspergillose und 25 differentialdiagnostischen Fällen bestehende Sammlung zusammengestellt. Die Fälle der multizentrischen Studie wurden verblindet, randomisiert und auf einer Fall-CD-ROM präsentiert. Ergebnisse: Die Internisten erreichten mittels alleiniger Klinik die höchste diagnostische Leistung und sie zeigten die größte Variabilität in ihrer Gruppe. Durch die zusätzliche Verfügbarkeit von Röntgenbildern, veränderte sich ihre diagnostische Leistung nicht. Die Radiologen konnten durch zusätzlich zum Röntgenthorax verfügbare klinische Informationen ihre diagnostische Leistung signifikant erhöhen. Schlussfolgerungen: Die klinischen Angaben hatten für die Differentialdiagnose der Aspergillose für Internisten und Radiologne eine hohen diagnostischen Wert. Radiologen brauchen deshalb einen kompletten Zugang zu den spezifischen klinischen Informationen. Der Röntgenthorax zeigte für die radiologisch charakteristischen Aspergillosen und für die Differentialdiagnosen eine hohe Aussagekraft. Als Basis in der diagnostischen Bildgebung sollte sich der Diagnostiker der Stärken und Limitationen dieser konventionellen Bildgebung bewußt sein. / Objective: The role of clinical information and chest film alone and combined for the discrimination between invasive pulmonary aspergillosis (IPA) and its differential diagnoses in human immunodeficiency virus (HIV) infection was studied. Design: Receiver operating characteristics (ROC) methodology was employed to determine separate diagnostic performances. Methods: The diagnostic performance of clinical information and chest film alone and in combination was studied separately for 8 internists and 8 radiologists with regular exposure to HIV and IPA patients. The multicenter ROC case sample consisted of 25 patients with proven IPA and 25 with other proven pulmonary disease entities typical for HIV. The cases were blinded, randomized and presented on a CD-ROM using HTML. Results: With clinical information alone internists achieved the highest diagnostic performance in the discrimination between IPA and its differential diagnoses. Viewing the chest films did not contribute to their performance. The radiologist's performance on the basis of viewing the chest film alone increased significantly when clinical information was supplied. Conclusion: For internists with regular exposure to HIV patients chest films do not provide information essential for the verification or differentiation of potential IPA. Radiologists with regular exposure to HIV patients need full access to the clinical data to reach a comparable performance. Chest films hold relevant information and contribute to the determination of cases with characteristic radiological appearance. Close cooperation between internists and radiologists is mandatory in challenging cases.
15

Apport de la protéomique dans l'amélioration de l'exploration de l'aspergillose pulmonaire invasive à partir d'un modèle murin / Interest of proteomics in improving the investigation of invasive pulmonary aspergillosis by the means of a murine model

Desoubeaux, Guillaume 16 December 2013 (has links)
Infection fongique opportuniste, l’aspergillose pulmonaire invasive reste redoutée au sein des services hospitaliers d’onco-hématologie, de réanimation ou de transplantations d’organes. Le diagnostic, tant clinique que biologique, souffre globalement d’un manque de sensiblité et de spécificité. De ce fait, le développement de nouveaux marqueurs d’infection semble nécessaire pour améliorer la prise en charge des patients à risque. Dans ce sens, nous avons d’abord mis au point un modèle murin nous permettant d’explorer la maladie aspergillaire avec reproductibilité. Nous avons ensuite étudié le compartiment pulmonaire des rats grâce à deux techniques permettant l’exploration protéomique de leurs liquides de lavages broncho-alvéolaires (LBA). La spectrométrie de masse MALDI-TOF a premièrement dessiné des profils protéiques reproductibles, spécifiques de l’état infecté. L’électrophorèse bidimensionnelle, suivie d’une étude comparative statistique, a ensuite sélectionné 20 spots protéiques surrepreséntés au cours de l’aspergillose expérimentale. Leur caractérisation en spectrométrie de masse a abouti à l’identification de 16 protéines, dont une présentait un intérêt tout particulier car jamais décrite jusqu’ici : ITIH4. Une analyse par western blotting a confirmé la surabondance de cette protéine dans tous les LBA de rats malades, ainsi que son augmentation relative dans le sérum après initiation de l’aspergillose expérimentale. De même, une tendance similaire a été observée dans des LBA d’origine humaine. / Opportunistic fungal infection, invasive aspergillosis is still much feared in the hematologyoncology departments, intensive care units and organ transplant centres. Diagnosis globally suffers from a lack of sensibility and specificity. Therefore, the development of new markers of infection seems necessary to improve the management of patients at risk. In this sense, we first developed a rat model which closely mimics the human disease. We were then able to study the pulmonary compartment of infected rats by the means of two proteomic techniques carried out within their bronchial-oalveolar lavage fluids (BALF). MALDI-TOF mass spectrometry first designed reproducible protein profiles of infected BALF, like a finger print. Two-dimensional electrophoresis, followed by a comparative statistical study, then selected 20 spots overrepresented in experimental aspergillosis. Their characterization by mass spectrometry led to the successful identification of 16 proteins. One of them was of a particular interest because never described so far: ITIH4. Analysis by western blotting confirmed the overabundance of this protein in all infected rat BALF, as well as a relative increase in the serum after initiation of the experimental aspergillosis. Likewise, a similar trend was observed in BALF of human origin.
16

Evolução da aspergilose pulmonar invasiva produzida em camundongos tratados com anticorpos monoclonais anti GR-1/Ly-6G e infectados com amostras de Aspergillus fumigatus que apresentaram distintos padrões de produção de elastase / Evolution of invasive pulmonary aspergillosis produced in mice treated with monoclonal antibodies anti GR-1/Ly-6G and infected with Aspergillus fumigatus strains which presented distincts patterns of production of elastase.

Raphael Luiz de Holanda e Silva 02 April 2012 (has links)
Aspergilose Pulmonar Invasiva é uma doença fúngica oportunista, causada principalmente por Aspergillus fumigatus, que acomete pacientes imunodeprimidos. Para melhor compreensão dessa micose inicialmente estabelecemos em camundongos C57BL/6 um modelo experimental de depleção de neutrófilos por inoculação intraperitoneal de anticorpos anti-GR-1/Ly-6G, confirmado por contagem total e diferencial de leucócitos sanguíneos. A seguir, avaliamos a evolução da infecção pulmonar experimental utilizando duas amostras de A. fumigatus, caracterizadas previamente em fraca (amostra 699) e forte (amostra 1753) produtoras de elastase. Nenhum dos animais imunocompetentes e infectados evoluiu para o óbito, no período de 7 dias de observação. Os animais neutropênicos, infectados por ambas as amostras, apresentaram 100% de mortalidade após 5 dias, com curvas de sobrevivência praticamente sobrepostas, sugerindo que a maior contribuição para a virulência foi a condição imunológica e não a atividade de elastase da amostra fúngica. Para análise do comprometimento pulmonar, os animais foram sacrificados nos tempos 24, 48 e 72 horas pós-infecção. Durante a evolução da infecção experimental foi observada uma redução da carga fúngica nos pulmões dos animais, para ambas as amostras de A. fumigatus, mas não foi observada uma redução da carga fúngica, diferenciada e estatisticamente significativa, entre os grupos de animais neutropênicos e imunocompetentes. O padrão celular do infiltrado inflamatório observado nos pulmões dos animais neutropênicos, infectados por qualquer uma das amostras de A. fumigatus, mostrou predominância de células mononucleares, em infiltrados difusos, indícios de angioinvasão e invasão brônquica com ruptura de fibras elásticas em ambas as estruturas, além de exuberância de filamentação dos conídios para ambas as amostras fúngicas, desde os tempos iniciais da infecção experimental. O processo inflamatório observado nos pulmões dos animais imunocompetentes, infectados por ambas as amostras de fungos, foi constituído nos tempos iniciais por neutrófilos e se tornou exuberante após 72 horas, com predomínio de macrófagos. Foi observada integridade de vasos sanguíneos e discreta ruptura de parede brônquica no parênquima pulmonar. Para estes animais, salienta-se a ausência de transformação dos conídios de A. fumigatus em hifas para a amostra 699, em todos os períodos de observação. A contagem total de leucócitos no lavado broncoalveolar (LBA) foi significativamente maior, 72 horas pós-infecção, para os animais neutropênicos e imunocompetentes, infectados por ambas as amostras do fungo. A contagem diferencial revelou a presença de macrófagos e neutrófilos, com a primeira célula sempre em maior quantidade no LBA dos animais neutropênicos em comparação com os animais imunocompetentes, independentemente do período da infecção e da amostra fúngica infectante. Ao contrário, o número de neutrófilos foi sempre mais relevante nos animais imunocompetentes. Por microscopia eletrônica de transmissão foi observado que a interação do fungo (conídios ou hifas) com as células de defesa do LBA envolveu íntima adesão e fusão entre os componentes de superfície de ambas as células. A presença de hemoglobina no LBA foi oriunda de lesão alvéolo-capilar causada pelo crescimento e invasão provocados pelas amostras fúngicas ou por lesão determinada pela própria reação inflamatória. Concluímos que os neutrófilos são essenciais na defesa contra A. fumigatus, pois na ausência dessa população celular os fungos rapidamente invadem e lesam o parênquima pulmonar. No entanto, deve-se considerar que a simples presença do fungo em animais imunocompetentes induz a migração de neutrófilos para o sítio da infecção, os quais também causam dano tecidual. As amostras de A. fumigatus com perfis distintos de produção de elastase não refletiram em diferenças significantes para a mortalidade ou gênese das lesões pulmonares observadas em camundongos neutropênicos, sugerindo que embora a elastase contribua para a ruptura das fibras elásticas observadas no tecido pulmonar, outros fatores de virulência, como a morfogênese, podem assumir um papel mais relevante para a patogênese da API experimental. / Invasive Pulmonary Aspergillosis (IPA) is an opportunistic fungal disease, caused mainly by Aspergillus fumigatus, that affects immunocompromised patients. To better understand this mycoses, we originally established in C57BL/6 mice an experimental model of neutrophils depletion by intraperitoneal inoculation of antibodies anti GR-1/Ly-6G, confirmed by total and differential leukocyte counts from blood. Next, we evaluated the evolution of experimental pulmonary infection using two strains of A. fumigatus, previously characterized as weak (strain 699) and strong (strain 1753) elastase producers. None of immunocompetent infected mice died with 7 days of observation, while neutropenic mice, infected with both strains, showed 100% mortality after 5 days, with survival curves nearly overlap, suggesting that the major contribution to the virulence was the immune status instead of elastase activity of each fungal strain. For analysis of lung parenchyma, mice were sacrificed 24, 48 and 72 hours post-infection. During the course of experimental infection it was observed a reduction of fungal burden in the lungs, for both strains of A. fumigatus, but this reduction was not statistically significant between the infected groups (neutropenic and immunocompetent). The cellular pattern of the inflammatory infiltrate observed in lungs from neutropenic mice, infected with both strains of A. fumigatus, revealed a predominance of mononuclear cells, a diffuse pattern and clear evidences of angioinvasion, bronchial disruption with break of elastic fibers in both structures, besides exuberance of conidia filamentation for both fungal strains, since the early period of experimental infection. The inflammatory process observed in lungs from immunocompetent mice, infected with both fungal strains, was composed on early times by neutrophils and became exuberant after 72 hours, with predominance of macrophages. It was observed integrity of blood vessels and moderate bronchial wall disruption in lung parenchyma. A relevant observation was the lack of transformation of conidia in hyphae for 699 A. fumigatus strain, in all periods of observation. Total leukocytes count in bronchoalveolar lavage (BAL) was significantly higher at 72 hours post-infection for both groups infected with both strains. The differential count revealed the presence of macrophages and neutrophils, with the former always in greater percentage in BAL from neutropenic mice and the latter always more elevated in immunocompetent group. Analysis by transmission electron microscopy demonstrated that the interaction of fungal structures (conidia or hyphae) with the defense cells (neutrophlis or macrophages) of BAL involved an intimate adhesion and fusion between the surface components from both cells. The presence of hemoglobin in BAL was a result of alveolar injury caused by the fungal development and invasion, but also by injuries determined by the inflammatory process itself. We concluded that neutrophils have a critical role against A. fumigatus since the pathogen quickly invades and damages the lung parenchyma in its absence. However, we must consider that the mere presence of A. fumigatus in immunocompetent mice induces the neutrophils migration to the infection site, which can also cause a tissue injury. Strains of A. fumigatus with distinct patterns of elastase production did not reflect in significant differences in mortality or origin of pulmonary lesions observed in neutropenic mice, suggesting that although elastase contributes to elastic disruptions observed in pulmonary tissue, another virulence factors, such as morphogenesis, can assume a more relevant role for pathogenesis of experimental IPA.
17

Evolução da aspergilose pulmonar invasiva produzida em camundongos tratados com anticorpos monoclonais anti GR-1/Ly-6G e infectados com amostras de Aspergillus fumigatus que apresentaram distintos padrões de produção de elastase / Evolution of invasive pulmonary aspergillosis produced in mice treated with monoclonal antibodies anti GR-1/Ly-6G and infected with Aspergillus fumigatus strains which presented distincts patterns of production of elastase.

Silva, Raphael Luiz de Holanda e 02 April 2012 (has links)
Aspergilose Pulmonar Invasiva é uma doença fúngica oportunista, causada principalmente por Aspergillus fumigatus, que acomete pacientes imunodeprimidos. Para melhor compreensão dessa micose inicialmente estabelecemos em camundongos C57BL/6 um modelo experimental de depleção de neutrófilos por inoculação intraperitoneal de anticorpos anti-GR-1/Ly-6G, confirmado por contagem total e diferencial de leucócitos sanguíneos. A seguir, avaliamos a evolução da infecção pulmonar experimental utilizando duas amostras de A. fumigatus, caracterizadas previamente em fraca (amostra 699) e forte (amostra 1753) produtoras de elastase. Nenhum dos animais imunocompetentes e infectados evoluiu para o óbito, no período de 7 dias de observação. Os animais neutropênicos, infectados por ambas as amostras, apresentaram 100% de mortalidade após 5 dias, com curvas de sobrevivência praticamente sobrepostas, sugerindo que a maior contribuição para a virulência foi a condição imunológica e não a atividade de elastase da amostra fúngica. Para análise do comprometimento pulmonar, os animais foram sacrificados nos tempos 24, 48 e 72 horas pós-infecção. Durante a evolução da infecção experimental foi observada uma redução da carga fúngica nos pulmões dos animais, para ambas as amostras de A. fumigatus, mas não foi observada uma redução da carga fúngica, diferenciada e estatisticamente significativa, entre os grupos de animais neutropênicos e imunocompetentes. O padrão celular do infiltrado inflamatório observado nos pulmões dos animais neutropênicos, infectados por qualquer uma das amostras de A. fumigatus, mostrou predominância de células mononucleares, em infiltrados difusos, indícios de angioinvasão e invasão brônquica com ruptura de fibras elásticas em ambas as estruturas, além de exuberância de filamentação dos conídios para ambas as amostras fúngicas, desde os tempos iniciais da infecção experimental. O processo inflamatório observado nos pulmões dos animais imunocompetentes, infectados por ambas as amostras de fungos, foi constituído nos tempos iniciais por neutrófilos e se tornou exuberante após 72 horas, com predomínio de macrófagos. Foi observada integridade de vasos sanguíneos e discreta ruptura de parede brônquica no parênquima pulmonar. Para estes animais, salienta-se a ausência de transformação dos conídios de A. fumigatus em hifas para a amostra 699, em todos os períodos de observação. A contagem total de leucócitos no lavado broncoalveolar (LBA) foi significativamente maior, 72 horas pós-infecção, para os animais neutropênicos e imunocompetentes, infectados por ambas as amostras do fungo. A contagem diferencial revelou a presença de macrófagos e neutrófilos, com a primeira célula sempre em maior quantidade no LBA dos animais neutropênicos em comparação com os animais imunocompetentes, independentemente do período da infecção e da amostra fúngica infectante. Ao contrário, o número de neutrófilos foi sempre mais relevante nos animais imunocompetentes. Por microscopia eletrônica de transmissão foi observado que a interação do fungo (conídios ou hifas) com as células de defesa do LBA envolveu íntima adesão e fusão entre os componentes de superfície de ambas as células. A presença de hemoglobina no LBA foi oriunda de lesão alvéolo-capilar causada pelo crescimento e invasão provocados pelas amostras fúngicas ou por lesão determinada pela própria reação inflamatória. Concluímos que os neutrófilos são essenciais na defesa contra A. fumigatus, pois na ausência dessa população celular os fungos rapidamente invadem e lesam o parênquima pulmonar. No entanto, deve-se considerar que a simples presença do fungo em animais imunocompetentes induz a migração de neutrófilos para o sítio da infecção, os quais também causam dano tecidual. As amostras de A. fumigatus com perfis distintos de produção de elastase não refletiram em diferenças significantes para a mortalidade ou gênese das lesões pulmonares observadas em camundongos neutropênicos, sugerindo que embora a elastase contribua para a ruptura das fibras elásticas observadas no tecido pulmonar, outros fatores de virulência, como a morfogênese, podem assumir um papel mais relevante para a patogênese da API experimental. / Invasive Pulmonary Aspergillosis (IPA) is an opportunistic fungal disease, caused mainly by Aspergillus fumigatus, that affects immunocompromised patients. To better understand this mycoses, we originally established in C57BL/6 mice an experimental model of neutrophils depletion by intraperitoneal inoculation of antibodies anti GR-1/Ly-6G, confirmed by total and differential leukocyte counts from blood. Next, we evaluated the evolution of experimental pulmonary infection using two strains of A. fumigatus, previously characterized as weak (strain 699) and strong (strain 1753) elastase producers. None of immunocompetent infected mice died with 7 days of observation, while neutropenic mice, infected with both strains, showed 100% mortality after 5 days, with survival curves nearly overlap, suggesting that the major contribution to the virulence was the immune status instead of elastase activity of each fungal strain. For analysis of lung parenchyma, mice were sacrificed 24, 48 and 72 hours post-infection. During the course of experimental infection it was observed a reduction of fungal burden in the lungs, for both strains of A. fumigatus, but this reduction was not statistically significant between the infected groups (neutropenic and immunocompetent). The cellular pattern of the inflammatory infiltrate observed in lungs from neutropenic mice, infected with both strains of A. fumigatus, revealed a predominance of mononuclear cells, a diffuse pattern and clear evidences of angioinvasion, bronchial disruption with break of elastic fibers in both structures, besides exuberance of conidia filamentation for both fungal strains, since the early period of experimental infection. The inflammatory process observed in lungs from immunocompetent mice, infected with both fungal strains, was composed on early times by neutrophils and became exuberant after 72 hours, with predominance of macrophages. It was observed integrity of blood vessels and moderate bronchial wall disruption in lung parenchyma. A relevant observation was the lack of transformation of conidia in hyphae for 699 A. fumigatus strain, in all periods of observation. Total leukocytes count in bronchoalveolar lavage (BAL) was significantly higher at 72 hours post-infection for both groups infected with both strains. The differential count revealed the presence of macrophages and neutrophils, with the former always in greater percentage in BAL from neutropenic mice and the latter always more elevated in immunocompetent group. Analysis by transmission electron microscopy demonstrated that the interaction of fungal structures (conidia or hyphae) with the defense cells (neutrophlis or macrophages) of BAL involved an intimate adhesion and fusion between the surface components from both cells. The presence of hemoglobin in BAL was a result of alveolar injury caused by the fungal development and invasion, but also by injuries determined by the inflammatory process itself. We concluded that neutrophils have a critical role against A. fumigatus since the pathogen quickly invades and damages the lung parenchyma in its absence. However, we must consider that the mere presence of A. fumigatus in immunocompetent mice induces the neutrophils migration to the infection site, which can also cause a tissue injury. Strains of A. fumigatus with distinct patterns of elastase production did not reflect in significant differences in mortality or origin of pulmonary lesions observed in neutropenic mice, suggesting that although elastase contributes to elastic disruptions observed in pulmonary tissue, another virulence factors, such as morphogenesis, can assume a more relevant role for pathogenesis of experimental IPA.
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Eosinophils as Drivers of the IL-23/IL-17 Axis: Implications for Acute Aspergillosis and Allergic Asthma: A Dissertation

Guerra, Evelyn V. Santos 23 February 2016 (has links)
Aspergillus fumigatus is an opportunistic fungal pathogen that causes lethal invasive pulmonary disease in immunocompromised hosts and allergic asthma in sensitized individuals. This dissertation explores how eosinophils may protect hosts from acute infection while driving asthma pathogenesis by co-producing IL-23 and IL-17 in both contexts. In an acute model of pulmonary aspergillosis, eosinophils were observed to associate with and kill A. fumigatus spores in vivo. In addition, eosinopenia was correlated with higher mortality rates, decreased recruitment of inflammatory monocytes to the lungs, and decreased expansion of lung macrophages. As IL-17 signaling must occur on a local level to elicit its stereotypical response, such as the up-regulation of antimicrobial peptides and specific chemokines from stromal cells, eosinophils were discovered to be a significant source of pulmonary IL-17 as well as one of its upstream inducers, IL-23. In the context of asthma, this discovery opens a new paradigm whereby eosinophils might be driving asthma pathogenesis.
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Développement et évaluation de poudres sèches pour inhalation à base d'itraconazole dans le cadre du traitement et de la prévention de l'aspergillose pulmonaire

Duret, Christophe 19 April 2013 (has links)
Compte tenu de ses aspects multiples, de sa dangerosité potentielle et du taux de<p>survie considérablement bas qui lui est associé dans ses formes les plus graves, l’aspergillose<p>pulmonaire est encore à l’heure actuelle dévastatrice sur le plan clinique. L’approche<p>médicamenteuse conventionnelle consiste en l’administration par voie orale ou<p>intraveineuse (IV) d’agents antifongiques. Ces voies classiques requièrent l’administration de<p>doses très élevées qui sont nécessaires à l’obtention de concentrations systémiques<p>suffisantes pour obtenir un effet thérapeutique au niveau pulmonaire. Cependant, ces<p>concentrations systémiques sont également la cause d’effets secondaires indésirables et<p>d’interactions médicamenteuses importantes. Une alternative thérapeutique à ces voies<p>classiques serait de localiser ces antifongiques dans le poumon, en utilisant la voie inhalée.<p>Cela permettrait d’augmenter le taux de succès thérapeutique en déposant et en<p>concentrant directement la dose au niveau du site d’infection tout en minimisant les<p>concentrations systémiques.<p>Pour ce faire, nous avons choisi de développer des poudres sèches pour inhalation à<p>base d’itraconazole (ITZ), un antifongique actif à l’égard des souches d’aspergillus. Celles-ci<p>sont administrable via un inhalateur à poudre sèche pour les avantages que présente ce<p>mode d’administration comparativement aux nébuliseurs et aux inhalateurs pressurisés. Le<p>développement des formulations implique entre autres l’obtention de caractéristiques<p>aérodynamiques appropriées, c’est-à-dire, ayant, après décharge à partir d’un dispositif<p>d’inhalation, un profil de déposition pulmonaire permettant d’atteindre des doses<p>pulmonaires pharmacologiquement efficaces. Toutefois, l’ITZ présente une solubilité<p>aqueuse extrêmement faible (solubilité aqueuse à pH 7 ~ 4 ng/ml à 25°C). Or, une fois<p>déposée dans le poumon, la dose inhalée doit se solubiliser pour exercer son action<p>pharmacologique. Nous avons donc inclus dans les concepts de formulation, une stratégie<p>permettant l’amélioration du profil de dissolution et l’augmentation de la solubilité de l’ITZ.<p>Cela permettrait en effet d’en potentialiser au maximum l’action pharmacologique au sein<p>des lésions fongiques avant qu'il ne soit éliminé sous sa forme non dissoute par les<p>mécanismes de clairance non absorptifs du poumon. De plus, le poumon étant un organe ne<p>tolérant qu’un nombre limité de substances administrables par inhalation, nous nous<p>sommes focalisés sur l’utilisation d’excipients présentant un faible potentiel toxique ou bien<p>tolérés après inhalation. Enfin, nous avons gardé à l’esprit lors du développement des procédés de fabrication qu’ils pouvaient être sujets à la mise à l’échelle industrielle. Nous<p>avons donc privilégié des procédés de fabrication simples incluant des technologies<p>transposables telles que l’atomisation par la chaleur et l’homogénéisation à haute pression.<p>Une attention particulière lors de la caractérisation des poudres a été portée sur les<p>propriétés d’écoulement des formulations, toujours dans l’optique de faciliter une<p>potentielle future manutention à plus grande échelle.<p>Pour répondre à ces critères, durant la première partie de ce travail, nous avons<p>imaginé deux concepts de formulation qui ont pour but de former des microparticules de<p>mannitol dans lesquelles est dispersé l’ITZ sous forme « modifiée ».<p>Le premier concept de formulation qui a été développé consistait à former une<p>dispersion solide (DS) entre l’ITZ, si possible amorphe pour en augmenter la solubilité, et un<p>agent matriciel en utilisant le procédé d’atomisation par la chaleur d’une solution contenant<p>tous les ingrédients sous forme dissoute. Lors de tests préliminaires, nous avons évalué trois<p>types d’agents matriciels, deux agents hydrophiles (le mannitol et le lactose) et un agent<p>hydrophobe (le cholestérol). Sur base de la faisabilité, des résultats préliminaires de<p>solubilité, de dissolution et de déposition pulmonaire in vitro, le mannitol a été retenu.<p>Après une optimisation des conditions d’atomisation, les formulations ont été produites en<p>vue d’être caractérisées. Il a été observé, par diffraction de rayons X sur poudre (PXRD) et<p>par calorimétrie différentielle à balayage (DSC), qu’après atomisation, l’ITZ était obtenu sous<p>forme amorphe et le mannitol sous forme cristalline. Les tests d’évaluation des propriétés<p>aérodynamiques ont été réalisés à l’aide d’un impacteur liquide multi-étages (MsLI) en<p>suivant les recommandations pratiques de la Pharmacopée européenne. Ce type de<p>compositions, atomisées dans les conditions optimales, permettait d’obtenir des poudres<p>sèches présentant les caractéristiques de taille (diamètre médian < 5 μm, mesuré par<p>diffraction laser) et les propriétés aérodynamiques appropriées à l’administration<p>pulmonaire (fraction de particules fines (FPF) déterminées lors des tests d’impaction<p>comprises entre 40 % et 70 %). La formation d’une DS avec le mannitol était nécessaire afin<p>d’augmenter la solubilité et d’accélérer la cinétique de dissolution de l’ITZ comparativement<p>à son homologue micronisé sous forme cristalline ou encore à sa forme amorphe atomisée<p>sans mannitol. Par exemple, dans sa configuration amorphe atomisée sans excipient ou sous<p>sa forme cristalline initiale, l’ITZ présentait une solubilité à saturation (mesurée dans un tampon phosphate contenant 0,02% de dipalmytoyl phosphatidyl choline) inférieure à 10<p>ng/ml. Après formation d’une DS avec le mannitol suivant notre procédé de formulation,<p>nous sommes parvenus à des valeurs de solubilité atteignant 450 ng/ml. Il s’est avéré que<p>l’ajout à la composition d’un surfactant, le tocopherol polyethylène glycol 1000 succinate<p>(TPGS), permettait d’accélérer la cinétique de dissolution du principe actif. Toutefois,<p>l’utilisation du TPGS induisait une diminution des performances aérodynamiques des<p>formulations. Etant donné que cette augmentation de la cinétique de dissolution pouvait<p>être un avantage après administration pulmonaire, nous avons considéré un autre type de<p>surfactant, les phospholipides (PL). L’utilisation de la lécithine de soja hydrogéné s’est<p>révélée être très efficace. Les performances aérodynamiques des formulations ont été<p>préservées et même améliorées. Leur incorporation à la DS permettait également d’obtenir<p>une accélération du profil de dissolution de l’ITZ. De plus, l’augmentation de la quantité de<p>PL dans nos formulations, dans la gamme des concentrations utilisées, était corrélée avec<p>une amélioration d’autant plus marquée du profil de dissolution de l’ITZ. En outre, les<p>solubilités de l’ITZ en présence de PL furent considérablement améliorées avec, par<p>exemple, des concentrations mesurées de 870 ng/ml et 1342 ng/ml pour les formulations<p>contenant respectivement 10 % (m/mpoudre) et 35 % (m/mpoudre) d’ITZ, ainsi que 10 % de PL<p>exprimés par rapport à la quantité d’ITZ.<p>Le deuxième concept de formulation développé consistait à produire des<p>microparticules de mannitol dans lesquelles étaient dispersées des nanoparticules (NP)<p>cristallines d’ITZ. Le procédé de fabrication était le suivant. Une suspension de nanocristaux<p>d’ITZ produite par homogénéisation à haute pression (HPH) était re-suspendue dans une<p>solution de mannitol qui était par la suite atomisée pour obtenir les microparticules de<p>poudres sèches. Après optimisation des conditions d’homogénéisation, nous sommes<p>parvenus à produire des nanosuspensions d’ITZ dont les particules présentaient un diamètre<p>médian inférieur à 250 nm. Nous avons alors évalué l’influence qu’avait l’ajout du mannitol<p>et du taurocholate sodique sur l’état d’agrégation des NP avant l’étape d’atomisation et sur<p>les performances des formulations sous forme sèche. Il a été observé que l’ajout de<p>mannitol était nécessaire à la production de solutions sursaturées en ITZ avec une solubilité<p>maximale d’ITZ mesurées à 96 ng/ml dans le tampon phosphate précédemment cité. L’ajout<p>de mannitol s’est avéré nécessaire afin de minimiser le phénomène d’agrégation des NP durant l’étape d’atomisation. De plus, l’ajout de taurocholate de sodium permettait<p>également d’inhiber leur agrégation. La cristallinité des NP d’ITZ a été confirmée par PXRD et<p>DSC. Ce type de formulation présentait des tailles et des performances aérodynamiques<p>compatibles à l’administration pulmonaire (tailles des particules < 5 μm et FPF entre 35 % et<p>46 %). Néanmoins, comparativement aux DS précédemment décrites, ces formulations à<p>base de NP s’avèrent sensiblement moins performantes. En effet, au niveau des<p>caractéristiques aérodynamiques, les formulations à base de NP présentent des FPF<p>nettement inférieures à celles obtenues pour les DS (FPF de ~40 % pour les formulations<p>nanoparticulaires contre ~70 % pour les DS d’ITZ amorphe). De plus, à partir des<p>formulations à bases de NP, les taux de sursaturation en ITZ atteints étaient nettement<p>inférieurs à ceux obtenus avec les DS (~100 ng/ml Vs > 1000 ng/ml pour les meilleurs DS). En<p>outre, la production des nanosuspensions nécessitait l’étape supplémentaire d’un minimum<p>de 300 cycles d’homogénéisation, ce qui représente un désavantage considérable en termes<p>de rendement économique en cas de transposition à échelle industrielle comparativement à<p>l’étape unique nécessaire pour la fabrication des DS. Pour ces raisons, seules les DS ont été<p>évaluées in vivo.<p>Après la mise au point des formulations, la seconde partie de ce projet consistait à<p>évaluer les DS développés dans un système biologique complet, la souris. Nous avons en<p>premier lieu réalisé une pharmacocinétique (PK) après administration pulmonaire pour<p>déterminer l’effet de l’augmentation de la solubilité observée in vitro et de l’ajout de PL dans<p>la formulation. Ensuite, nous avons entrepris une étude d’activité sur un modèle murin<p>d’aspergillose pulmonaire invasive (API) permettant de comparer l’efficacité thérapeutique<p>ou prophylactique de nos formulations comparativement à une thérapie standard par voie<p>orale. Pour effectuer ces deux études, nous avons préalablement validé une méthode<p>d’administration des poudres sèches chez la souris à l’aide d’un insufflateur (DP-4M®, Penn<p>Century, Wyndmoor, USA) en utilisant la voie endotrachéale. Le premier point de cette<p>investigation avait pour objet de déterminer si l’intervalle de taille particulaire généré lors de<p>la décharge de nos formulations au sortir de l’insufflateur permettait une répartition<p>homogène dans les poumons ainsi qu’une pénétration profonde des particules jusqu’aux<p>alvéoles pulmonaires. Le deuxième point sur lequel nous nous sommes également attardés était la reproductibilité des doses pulmonaires générées après insufflation, facteur<p>déterminant lors de la réalisation d’une étude PK.<p>Sur base des observations constatées durant la validation du dispositif<p>d’administration, nous avons entrepris une étude PK après administration pulmonaire d’une<p>dose de 0,5 mg/kg d’ITZ, représentant une quantité inhalable par l’homme et pouvant<p>garantir des taux pulmonaires en antifongiques théoriquement adéquats. Cette étude a<p>permis de comparer les concentrations pulmonaires et plasmatiques en ITZ après<p>l’administration de poudres sèches à base d’une DS de mannitol et d’ITZ qui était soit<p>cristallin soit amorphe, avec ou sans PL. Après administration de la DS à base d’ITZ sous sa<p>forme amorphe, une augmentation de la quantité d’ITZ absorbée vers le compartiment<p>systémique a été observée. En effet, il a été observé une augmentation d’un facteur 2,7 de<p>l’aire sous la courbe des concentrations plasmatiques en ITZ de 0 à 24 heures (AUC0-24h)<p>comparativement à celle obtenue après administration de la DS à base d’ITZ sous sa forme<p>cristalline. Le temps pour atteindre la concentration plasmatique maximale (tmax) était<p>également plus court pour la formulation à base ITZ sous sa forme amorphe (tmax de 10 min<p>vs 30 min pour la formulation cristalline). De plus, dans cette configuration amorphe, les<p>temps de rétention pulmonaire en ITZ étaient considérablement plus élevés (t1/2<p>d’élimination de 6,5 h pour l'ITZ cristallin vs 14 ,7 h pour l’ITZ amorphe) permettant de<p>maintenir une concentration pulmonaire en ITZ supérieure à la CMI de la souche<p>d’aspergillus la plus fréquente (A. fumigatus ;2 μg/gpoumon) pendant plus de 24h. L’ajout de<p>PL dans un rapport ITZ:PL:mannitol (1:3:97) dans la DS influençait le profil PK de l’ITZ<p>amorphe en accentuant et accélérant d’avantage la phase d’absorption initiale de l’ITZ<p>observée (Cmax et tmax plasmatique supérieur et inférieur à ceux obtenus pour l’ITZ amorphe,<p>respectivement). Toutefois, cette formulation a été éliminée plus rapidement des poumons<p>(t1/2 d’élimination pulmonaire de l’ITZ de 4,1h pour les formulations avec PL vs 14,7h sans<p>PL). Pour cette raison, nous avons décidé d’évaluer l’efficacité des formulations à base d’ITZ<p>sous forme amorphe sans phospholipides dans un modèle murin d’aspergillose pulmonaire<p>invasive (API) que nous avons développé.<p>Nous ne sommes pas parvenus à mettre en évidence un effet thérapeutique de<p>l’administration des poudres sèches administrées dans ce modèle murin neutropénique<p>d’API. Nous justifions ce manque d’activité par une agressivité du modèle trop prononcée et par l’impossibilité de pouvoir administrer de manière plus fréquente le traitement par<p>inhalation en raison de l’anesthésie nécessaire pour la procédure d’administration<p>endotrachéale. Toutefois, des essais complémentaires vont être envisagés (modification de<p>la charge fongique, administration des poudres par une tour d’inhalation, optimisation du<p>dosage et de la fréquence d’administration). En revanche, il a été mis en évidence que<p>l’administration prophylactique (début des administrations 2 jours avant l’infection) d’une<p>dose de 5 mg/kg/48h d’une DS d’ITZ amorphe augmentait significativement le taux de survie<p>de 12 jours après l’infection par A. fumigatus comparativement aux animaux non traités<p>(taux de survivants :50 % vs 0 %). A titre de comparaison, le pourcentage de survie obtenu<p>après prophylaxie quotidienne d’une dose de 12,5 mg/kg/12h de solution orale de VCZ (la<p>thérapie recommandée pour l’API) n’était que de 25 %.<p>En conclusion, les DS d’ITZ destinées à être administrées par inhalation constituent<p>une approche thérapeutique prometteuse dans le cadre de la prévention et du traitement<p>de l’aspergillose pulmonaire. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
20

Aspergilose invasiva em pacientes imunodeprimidos: comparação entre as provas de galactomanana, 1,3 betaD-glucana, dados tomográficos e desfecho clínico / Performance of galactomannan and 1,3 beta-glucan enzyme assays in the serum and bronchoalveolar lavage and comparison with computer tomography scan for the diagnosis of invasive aspergillosis in immunocompromised hosts

Batista, Marjorie Vieira 15 April 2015 (has links)
A aspergilose invasiva (AI) é a infecção por fungos filamentosos mais comum em pacientes imunodeprimidos, especialmente em transplantes de células tronco hematopoiético e neoplasias hematológicas. Objetivo: Geral: Estabelecer a comparação entre a dosagem de Galactomanana (GM), 1,3betaD-glucana (BDG) e dados tomográficos no diagnóstico da AI bem como seu papel no desfecho clínico. Específicos: 1. Verificar a sensibilidade e especificidade dos ensaios de Galactomanana e de 1,3betaD-glucana no soro e lavado broncoalveolar. 2. Comparar os resultados da galatomanana e 1,3betaD-glucana com os dados de imagem em pacientes com suspeita de AI. 3. Verificar a relação entre a evolução dos níveis de GM e desfecho clínico (óbito e sobrevida). Casuística, Materiais e Métodos: Realizou-se um estudo tipo coorte prospectiva, incluindo 398 sujeitos das diversas enfermarias de pacientes imunodeprimidos do HCFMUSP, sendo incluídos dois grupos de pacientes: 202(51%) AI e 198(49%) controles. Resultados: Dos casos, 18 (8,8%) tinham aspergilose provada, 28 (13,7%) provável e 158 possível (77,5%), de acordo a classificação de 2002 EORTC/MSG (European Organization for Research and Treatment of Cancer / Mycoses Study Group). Os sujeitos submetidos ao TCTH eram 42,7%, com neoplasias hematológicas 37%, TOS 9% e outras doenças 11,3%. Os fatores de risco associados ao desenvolvimento da AI foram neutropenia, monocitopenia, uso de corticóide, presença de doença pelo citomegalovírus e rejeição ou doença do enxerto contra o hospedeiro. O fator de risco associado à evolução para o óbito foi a presença de AI. Foram observados bons desempenhos para a GM tanto no soro como no LBA com LR menores que os registrados na literatura. O melhor desempenho da GM no soro para aspergilose+provável ocorreu com LR de 0,35 com sensibilidade-S, especificidade-E, valor preditivo positivo- VPP), valor preditivo negativo-VPN) e área sob a curva-ASC de 54,4%, 73,4%, 50,8%, 76,2% e 0,64, sendo os valores superiores para aspergilose provada tanto na S, como E, VPN. No LBA os valores de S-E-VPP-VPN-ASC para GM para LR de 0,65 para aspergilose provável + provada foram 58,3%, 92,6%, 87,5%,71,4% e 0,75, sendo na aspergilose provada os valores de S, e VPN superiores. Nesta casuística, o melhor desempenho para BDG no soro apontou para uma LR de 100 pg/mL na aspergilose provável+provada, com 54,5%, 73,4%, 50,8% e 76,2%, 0,64 respectivamente para S-E-VPP-VPN-ASC. Para BDG no LBA, a LR na aspergilose provável + provada foi de 140 pg/mL, com os mesmos valores de 46,7%, 76,7%, 70%, 55,6% e 0.62, respectivamente. Conclusão: A GM no LBA e no soro foram úteis no diagnóstico da aspergilose mediante emprego de LR menores, sendo mais sensível na LBA, principalmente em estágios iniciais da forma angioinvasiva. A persistência de GM sérica foi relacionada ao óbito em relação à negativação da mesma. A proporção de concordância entre a TC e os biomarcadores no soro e no LBA variou de 0,5 a 0,6, com pequena concordância na estatística kappa. Excelente concordância foi observada entre dois radiologistas independentes, que analisaram de maneira cega as TC de sujeitos com aspergilose provada. Nesta casuística com inclusão de doenças sistêmicas e endêmicas, a BDG teve baixo desempenho diagnóstico / Invasive aspergillosis (IA) has become the leading infectious cause of death in immunocompromised hosts, particularly in subjects under SCTH and hematologic neoplasias. Objectives: General: To compare the performance of GM and BG tests in serum and bronchoalveolar lavage fluid (BAL) and computer tomography (CT) scans in the diagnosis of IA in immunocompromised hosts as well as their role in the patient outcome. Specific: 1. To analyse the sensitivity and specificity of Galactomannan and 1,3 betaD-glucan assays in the serum and bronchoalveolar lavage. 2. To compare the results of Galactomannan and 1,3betaD-glucan assays with CT scans in patients with invasive aspergilosis. 3. To analyse the relationship between the evolution of galactomannan levels and clinical outcome (death or survival). Patients, Materials and Methods: From December 2008 to March 2013, a prospective cohort of 398 patients from several wards of immunocompromised patients of Hospital das Clínicas, Faculdade de Medicina, University of São Paulo was included classified in two groups of patients: 202 (51%) with invasive aspergillosis (IA) and 198 (49%) control patients. Results: Considering 202 cases, 18(8.8%) were subjects with proven, 28(13.7%) with probable aspergillosis and 156(77.5%), with possible aspergillosis, according to 2002 EORTC/MSG (European Organization for Research and Treatment of Cancer/Mycoses Study Group) criteria. The most common underlying disease were: HSCT (42.7%), hematologic malignancy (37%), SOT (9%), or other diseases (11.3%). The main risk factors associated with IA were neutropenia, monocytopenia, patients under corticosterois, presence of CMV disease, and rejection or graft versus host disease. The risk factor associated with death was the presence of invasive aspergillosis. Good performances for serum and BAL GM were registered with lower cutoffs in the present workin relationship to those found in the literature. The best cutoff for proven + probable aspergillosis for serum GM was observed at 0.35 vallue with Sensitivity-S, Specificity-Sp, Positive Predictive value-PPV), Negative Predictive Value-NPV) and AUC of 54.4%, 73.4%, 50.8%, 76.2% and 0.64; the values for proven aspergillosis alone were higher for S, Sp and NPV. On BAL tests for GM (cutoff value of 0.65) in proven+probable aspergillosis we observed 58.3%, 92.6%, 87.5%,71.4%, 0.75, respectively as S-Sp-PPV-NPVAUC; the sensitivity and VPN were higher in proven aspergillosis alone. In this work, the best performance in proven+probable aspergillosis for serum BDG showed 100 pg/ML as cutoff value, with 54.5%, 73.4%, 50.8%,76.2%, 0.64 for S-Sp-PPVNPV- AUC, respectively. For BAL- BDG, the cut off for proven+probable aspergillosis was 140 pg/mL, and we observed 46.7%, 76.7%, 70.0%, 55.,6%, 0.62, respectively for for S-Sp-PPV-NPV-AUC. Conclusion: The serum and BAL GM are useful tests for diagnosis in early stages of angioinvasive form at lower cutoffs; BAL GM is more sensitive. Agreement proportion between CT scan and each biomarker in the serum or BAL ranged from 0.5-0.6, with low ? index. Perfect ? statistic was observed for analysis of CT scan of subjects in proven aspergillosis by two independent radiologists, blinded for diagnosis. Persistence of serum GM was associated to death in relationship with its negativation. BDG test showed low performance in this work, where systemic and endemic diseases were included

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