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() is a commensal organism of the gastrointestinal tract. It rarely causes hepatobiliary infections; however, in the presence of underlying inflammation, immunosuppression, or malignancy, it can cause hepatobiliary infection via an ascending route. Herein, we report a case of pyogenic liver abscess secondary to associated with cholangiocarcinoma, which was treated with ceftriaxone and metronidazole.

Chaque individu est exposé quotidiennement à des agents infectieux comme les bactéries, les champignons, les virus et les parasites sans pour autant développer une maladie. Cependant, certains vont développer des infections graves et récurrentes, causées par des microbes dont certains ont un faible pouvoir pathogène pour l’homme. Ceci suggère, qu’il existe entre les individus sensibles et résistants une variabilité au niveau du système immunitaire. Deux types de déficits immunitaires primitifs (DIP) de transmission mendélienne ont été décrits. Les DIP dit « classiques » sont monogéniques et prédisposent majoritairement à une susceptibilité infectieuse à large spectre d’agents pathogènes (un gène, plusieurs infections). Les seconds DIP sont également monogéniques mais sont responsables d’une susceptibilité infectieuse réduite à un groupe de pathogènes (un gène, un seul type d’infection). Chez de nombreux, patients, le défaut génétique responsable de DIP n’est pas identifié. Dans ce contexte, l’objectif de recherche de mon doctorat a été de caractériser deux DIP responsables d’une susceptibilité aux infections bactériennes. J’ai tout d’abord mis en évidence un nouveau mécanisme physiopathologique de la protéine NEMO, régulateur de la voie NF-κB, responsable d’un DIP associé à une dysplasie ectodermale anhidrotique (EDA). Ce mécanisme pathologique est caractérisé par une expression et une structure protéique conservées mais confère sélectivement un défaut de liaison de NEMO à l’ubiquitine, interaction essentielle dans l’activation de la voie NF-κB. Ceci démontre qu’une expression et une structure protéique normales n'excluent en rien un rôle pathologique de mutations dans le gène NEMO, dans un EDA-DIP. Dans un deuxième temps, j’ai mis en évidence un nouveau DIP affectant la voie de l’explosion oxydative spécifiquement dans les polymorphonucléaires et qui confère une susceptibilité sélective aux infections bactériennes de type pyogènes. Le patient étudié est né de parents consanguins et a présenté des infections récurrentes des voies respiratoires supérieures ainsi qu’une cellulite à Staphylococcus epidermidis. Par une approche génétique associant analyse de liaison et séquençage de l'exome, une mutation homozygote rare a été identifiée dans le gène codant NRAMP1. Cette mutation co-ségrège avec la maladie selon un mode de transmission autosomique récessif et altère spécifiquement l’expression de la protéine dans les granulocytes. Ce premier déficit en NRAMP1 décrit chez l’homme, compromet à la fois la voie de l’explosion oxydative et le contrôle de l’infection in vitro par Staphylococcus aureus dans les granulocytes. Cette étude implique NRAMP1 dans l'immunité contre les bactéries pyogènes via son rôle dans la production des espèces réactives de l’oxygène dans les granulocytes. Ce travail ouvre la voie vers un meilleur diagnostique et conseil génétique pour les patients souffrant de PID. / Human populations are exposed to infectious agents such as bacteria, fungi, viruses and parasites on a daily basis without developing any disease. However, a minority of individuals will suffer from infections to some microbes that are usually non-pathogenic to man, or will undergo severe and/or recurrent diseases usually easily treatable for others. This means that there is variability among individuals regarding their immune system, underlined by genetics between susceptible and resistant individuals. Two types of primary immuno deficiencies with a Mendelian mode of inheritance have been described. The first known as the classical primary immunodeficiency and is monogenic and predisposes in general to infections with a broad spectrum of infectious agents (one gene, multiple infections). The second type is also monogenic but predisposes generally to infections limited to a particular group of pathogens (one gene, one type of infection). The aim of my doctoral research was to characterize two new immunodeficiencies. First I highlighted a new physiopathological mechanism of the NEMO protein, a regulator of NF-κB pathway. This defect is characterized by normal protein expression and folding, but a specific defect of NEMO’s ubiquitin binding, which is an essential mechanism for the activation and regulation of the NF-κB pathway. This demonstrates that normal expression and structure of the protein do not exclude a pathological role of NEMO mutations in EDA-ID. I also described a new immune deficiency affecting the respiratory burst pathway in granulocytes which specifically confers a selective susceptibility to pyogenic bacterial infections. We studied a patient who was born from consanguineous parents, and who suffered from recurrent infections of the upper respiratory tract and cellulitis to S. epidermidis. By a genetic approach involving linkage analysis and exome sequencing, I identified a rare homozygous mutation (V484M) in the gene encoding for the NRAMP1 protein that co segregates with the disease with an autosomal recessive transmission. Specifically, this mutation impairs NRAMP1 protein expression in granulocytes, while expression remains normal in other phagocytic cells. NRAMP1 deficiency impairs both the respiratory burst and control of in vitro infection by S. aureus in granulocytes. Therefore, we identified the first NRAMP1 human deficiency. The mutation selectively affects granulocytes and is clinically responsible for pyogenic infections. This study helps to delineate the role of NRAMP1 in immunity against pyogenic bacteria through its involvement in reactive oxygen species production in granulocytes.

Made available in DSpace on 2014-12-17T15:32:16Z (GMT). No. of bitstreams: 1 MarceloGV.pdf: 2007167 bytes, checksum: 5ee7e9c9bd56fd72fecb1874fb64a80e (MD5) Previous issue date: 2008-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Angiogenesis, a fundamental mechanism in tumor development, is used for differential diagnosis and prognosis purposes in various neoplasias of the head and neck. This study proposes to assess angiogenic activity using immunohistochemical expression by anti-CD105 and anti-CD34 antibodies in 20 cases of hemangiomas and 20 cases of oral pyogenic granulomas, in addition to determining the usefulness of these markers as one of the differential diagnosis resources for these two oral lesions. The results showed no statistically significant difference between microvascular count (MVC) means determined by anti-CD105 (p = 0.803) and anti-CD34 (p = 0.279) antibodies. The mean number of vessels obtained by MVC in the oral hemangiomas immunostained by anti-CD105 and anti-CD34 was 18.75 and 59.72, respectively, whereas in the oral pyogenic granulomas, the mean number was 20.22 and 48.09 respectively. It was also shown that CD34 was more effective than CD105 in identifying blood vessels. However, it must be pointed out that the anti-CD105 antibody seems to be more related to vascular neoformation. Overall, this assay reinforces the role of angiogenic factors in the etiopathogenesis of hemangiomas and oral pyogenic granulomas, but the results showed that angiogenesis quantification cannot be used as a differential diagnosis parameter between the two lesions analyzed / A angiog?nese ? um mecanismo fundamental para o desenvolvimento tumoral, sendo utilizada para fins de diagn?stico diferencial e determina??o de progn?stico em v?rias neoplasias de cabe?a e pesco?o. Este trabalho se prop?s avaliar a atividade angiog?nica atrav?s da express?o imuno-histoqu?mica dos anticorpos anti-CD105 e anti-CD34 em 20 casos de hemangiomas e 20 casos de granulomas piog?nicos orais, al?m de averiguar a utilidade destes marcadores como um dos recursos de diagn?stico diferencial para estas duas les?es orais. Os resultados deste experimento demonstraram que n?o houve diferen?a estatisticamente significativa entre as m?dias de contagem microvascular (MVC) determinadas pelos os anticorpos anti-CD105 (p=0,803) e anti-CD34 (p=0,279). O n?mero m?dio dos vasos obtidos pela MVC nos esp?cimes de hemangiomas orais imunomarcados pelo anti-CD105 e anti-CD34 foram respectivamente 18,75 e 59,72, enquanto nos granulomas piog?nicos orais, o n?mero m?dio dos vasos obtidos pela MVC pelo anti-CD105 e anti-CD34 foram respectivamente 20,22 e 48,09. Foi verificado, tamb?m, que o CD34 foi mais efetivo na identifica??o de vasos sang??neos quando comparado com o CD105. Entretanto, faz-se necess?rio destacar, que o anticorpo anti-CD105 parece estar mais relacionado com a neoforma??o vascular. Em linhas gerais, este ensaio refor?a a participa??o dos fatores angiog?nicos na etiopatog?nese dos hemangiomas e granulomas piog?nicos orais, por?m os resultados mostraram que a quantifica??o da angiog?nese n?o pode ser utilizada como par?metro de diagn?stico diferencial entre as duas les?es analisadas

Made available in DSpace on 2014-12-17T15:32:23Z (GMT). No. of bitstreams: 1 TiagoJSF_DISSERT.pdf: 3045279 bytes, checksum: 8153fafe331060792baf7be0c25c538f (MD5) Previous issue date: 2014-02-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Vascular anomalies constitute a distinct group of lesions, but they may present similar clinical and histopatological characteristics, which can lead to diagnostic mistakes. This study aimed by histopathology and immunohistochemical expression of human glucose transporter protein (GLUT-1), correctly identify and classify oral vascular anomalies, besides analyzing the immunoexpression of markers proliferation and apoptosis (Ki-67 and Bcl-2). All cases diagnosed as "oral hemangiomas" belonging to the archives of the Service of Pathological Anatomy from the subject of Oral Pathology of the Department of Dentistry (DOD), of the Federal University of Rio Grande do Norte (UFRN) were reviewed, totalizing 77 cases. Immunohistochemical analysis for GLUT-1 showed that only 26 (33.8%) of the specimens were true infantile hemangiomas (IHs). The 51 (66.2%%) GLUT-1 negative specimens were then reclassified as pyogenic granulomas (PGs) and vascular malformations (VMs) from their histopathologic characteristics,totalizing 26 (33.8%) cases of IHs, 20 (26.0%) of PGs and 31 (40.2) cases of oral VMs. The cases analyzed by the marker Ki-67 showed different median IH (13,85), PG (33,70) and VM (4.55) with statistically significant differences between them (p <0.001). In relation to the protein Bcl-2, the groups also showed different median of the established scores IH (1.00), PG (1.50), VMs (0.0) demonstrating statistically significant differences between them (p<0,001). No statistically significant correlation between the indexes of positivity for Ki-67 and the scores of immunoexpression of Bcl-2 were observed in any group. Thus, we can conclude that it is necessary a careful and parameterized review of cases of vascular anomalies making use of auxiliary tools such as GLUT-1, since the histopathological findings alone, sometimes, are not sufficient to differentiate some anomalies. Furthermore, analysis of the expressions of markers involved in the levels of proliferation of lesions is important for a better understanding of its biological behavior aspect / As anomalias vasculares constituem um grupo de les?es distintas, mas que podem apresentar caracter?sticas cl?nicas e histopatol?gicas semelhantes, que podem levar a equ?vocos diagn?sticos.Este estudo objetivou por meio da histopatologia e da express?o imuno-histoqu?mica daprote?na humana transportadora de glicose (GLUT-1), identificar e classificar corretamente as anomalias vasculares orais, al?m de analisar a imunoexpress?o de marcadores de prolifera??o e apoptose (Ki-67 e Bcl-2).Todos os casos diagnosticados como hemangiomas orais pertencentes aos arquivos do Servi?o de Anatomia Patol?gica da disciplina de Patologia Oral do Departamento de Odontologia (DOD) da Universidade Federal do Rio Grande do Norte (UFRN) foram revisados, totalizando 77 casos. A an?lise imuno-histoqu?mica para GLUT-1 revelou que apenas 26 (33,8%) dos esp?cimes tratavam-se de hemangiomas da inf?ncia (HIs) verdadeiros. Os 51 (66,2%%)esp?cimes GLUT-1 negativos foram ent?o reclassificados em granulomas piog?nicos (GPs) e malforma??es vasculares (MVs) a partir de suas caracter?sticas histopatol?gicas, totalizando 26 (33,8%) casos de HIs, 20 (26,0%) de GPs e 31 (40,2) casos de MVs orais. Os casos submetidos ? an?lise do marcador Ki-67 apresentaram medianas diferentes HI (13,85), GP (33,70) e MV (4,55) com diferen?as estatisticamente significantes entre elas (p<0,001). Em rela??o ? prote?na Bcl-2, os grupos tamb?m apresentaram diferentes medianas dos escores estabelecidos HI (1,00), GP (1,50), MVs (0,0), demonstrando diferen?as estatisticamente significantes entre elas (p<0,001). N?o foi observada correla??o estatisticamente significante entre os ?ndices de positividade para o Ki-67 e os escores de imunoexpress?o de Bcl-2 em nenhum grupo.Dessa maneira, podemos concluir que se faz necess?rio uma revis?o criteriosa e parametrizada dos casos de anomalias vasculares utilizando ferramentas auxiliares, como a GLUT-1, uma vez que os achados histopatol?gicos sozinhos, ?s vezes, n?o s?o suficientes para diferenciar algumas anomalias. Al?m disso, a an?lise das express?es de marcadores envolvidos nos n?veis de prolifera??o das les?es ? um aspecto importante para o melhor entendimento do seu comportamento biol?gico