RESUMO
Dengue is a public health problem, with several gaps in understanding its pathogenesis. Studies based on human fatal cases are extremely important and may clarify some of these gaps. In this work, we analyzed lesions in different organs of four dengue fatal cases, occurred in Brazil. Tissues were prepared for visualization in optical and electron microscopy, with damages quantification. As expected, we observed in all studied organ lesions characteristic of severe dengue, such as hemorrhage and edema, although other injuries were also detected. Cases presented necrotic areas in the liver and diffuse macro and microsteatosis, which were more accentuated in case 1, who also had obesity. The lung was the most affected organ, with hyaline membrane formation associated with mononuclear infiltrates in patients with pre-existing diseases such as diabetes and obesity (cases 1 and 2, respectively). These cases had also extensive acute tubular necrosis in the kidney. Infection induced destruction of cardiac fibers in most cases, with absence of nucleus and loss of striations, suggesting myocarditis. Spleens revealed significant destruction of the germinal centers and atrophy of lymphoid follicles, which may be associated to decrease of T cell number. Circulatory disturbs were reinforced by the presence of megakaryocytes in alveolar spaces, thrombus formation in glomerular capillaries and loss of endothelium in several tissues. Besides histopathological and ultrastructural observations, virus replication were investigated by detection of dengue antigens, especially the non-structural 3 protein (NS3), and confirmed by the presence of virus RNA negative strand (in situ hybridization), with second staining for identification of some cells. Results showed that dengue had broader tropism comparing to what was described before in literature, replicating in hepatocytes, type II pneumocytes and cardiac fibers, as well as in resident and circulating monocytes/macrophages and endothelial cells.
Assuntos
Vírus da Dengue , Dengue Grave/patologia , Dengue Grave/virologia , Adulto , Evolução Fatal , Feminino , Coração/virologia , Humanos , Rim/patologia , Rim/ultraestrutura , Rim/virologia , Fígado/patologia , Fígado/ultraestrutura , Fígado/virologia , Pulmão/patologia , Pulmão/ultraestrutura , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Miocárdio/ultraestrutura , Dengue Grave/diagnóstico , Baço/patologia , Baço/ultraestrutura , Baço/virologia , Replicação Viral , Adulto JovemRESUMO
The mucoepidermoid carcinoma is a neoplasia that usually occurs at salivary glands, breast, pancreas and gastrointestinal tract. The primary occurrence on thyroid gland is rare and only 33 cases were previously published. Although the majority of cases of mucoepidermoid carcinoma of the thyroid (MECT) show a benign evolution, this paper describes a patient with an aggressive tumor. A literature review over clinical, histopathological, immunohistochemical features and histogenetic origin was discussed.
Assuntos
Carcinoma Mucoepidermoide/patologia , Carcinoma Papilar/secundário , Neoplasias da Glândula Tireoide/patologia , Calcitonina/análise , Carcinoma Mucoepidermoide/diagnóstico por imagem , Carcinoma Mucoepidermoide/ultraestrutura , Feminino , Humanos , Pessoa de Meia-Idade , Mucinas/metabolismo , Recidiva Local de Neoplasia/patologia , Prognóstico , Radiografia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/ultraestrutura , Tireoidectomia , Imagem Corporal TotalRESUMO
O carcinoma mucoepidermóide é um tipo de neoplasia encontrada geralmente nas glândulas salivares, mamas, pâncreas e trato digestivo. O acometimento primário da glândula tireóide é muito raro, apenas 33 casos na literatura. Embora a maioria dos casos de carcinoma mucoepidermóide de tireóide (CMET) tenha evolução favorável, o caso clínico relatado descreve uma paciente com tumor agressivo e, a partir deste relato, é apresentada revisão da literatura quanto aos aspectos clínico, histopatológico, imunohistoquímico e origem histogenética dessa neoplasia.
The mucoepidermoid carcinoma is a neoplasia that usually occurs at salivary glands, breast, pancreas and gastrointestinal tract. The primary occurrence on thyroid gland is rare and only 33 cases were previously published. Although the majority of cases of mucoepidermoid carcinoma of the thyroid (MECT) show a benign evolution, this paper describes a patient with an aggressive tumor. A literature review over clinical, histopathological, imunohistochemical features and histogenetic origin was discussed.