Toxoplasmosis ocular. Descripción de tres pacientes con presentación atípica / Ocular toxoplasmosis. Description of three patients with an atypical presentation.

Objetivo: Describir una forma de presentación atípica de toxoplasmosis ocular, enfatizando la importancia de la jerarquización de los hallazgos clínicos y las limitaciones de la serología para realizar un diagnóstico temprano. Pacientes y Métodos: Estudio retrospectivo y descriptivo de tres casos clínicos de toxoplasmosis ocular activa, con presentación atípica (compromiso del nervio óptico), derivados al Servicio de Oftalmología del Hospital J. P. Garrahan en el periodo comprendido entre 2007 y 2010. Resultados: En los tres casos presentados la sospecha clínica de toxoplasmosis ocular no se correlacionó con evidencia serológica de infección reciente. En un caso, la terapéutica específica temprana, basada en la sospecha clínica, resultó en una excelente recuperación funcional. Un tratamiento tardío puede interferir en el resultado visual. Conclusiones: Basados en los hallazgos clínicos y la alta sospecha de esta patología debe iniciarse el tratamiento específico sin esperar que los resultados serológicos la confirmen. Eventualmente, la mejoría clínica confirmara el diagnóstico. El comportamiento de los títulos de anticuerpos en el curso de la enfermedad ocular no siempre es confiable, y en muchos casos retrasa el comienzo de la terapéutica con la consiguiente mala rehabilitación visual de estos pacientes (AU)

Objective: To describe an atypical presentation of ocular toxoplasmosis, emphasizing the importance of clinical findings and the limitations of serology in the early diagnosis. Patients and Methods: A retrospective, descriptive study was conducted of three cases with active ocular toxoplasmosis with an atypical presentation (optic nerve involvement), referred to the Department of Ophthalmology of Hospital J. P. Garrahan between 2007 and 2010. Results: In the three cases presented here clinical suspicion of ocular toxoplasmosis did not correlate with serological evidence of a recent infection. In one case, early treatment, based on clinical suspicion, resulted in excellent functional recovery. Late management may compromise visual outcome. Conclusions: Based on clinical findings and suspicion of the pathology, specific treatment should be started without waiting for serological confirmation. Eventually, clinical improvement will confirm the diagnosis. The behavior of antibody titres in the course of the ocular disease is not always reliable and often delays treatment initiation with subsequent difficulties in the visual rehabilitation of these patients (AU)

Avaliação da resposta inflamatória tecidual de pacientes com leishmaniose cutânea recente / Evaluation of tissue inflammatory response in patients with recent cutaneous leishmaniasis

Introdução: A leishmaniose cutânea (LC) é a forma clínica mais frequente da leishmaniose humana, considerada um importante problema de saúde no Brasil. A infecção por Leishmania braziliensis induz um amplo espectro de lesões que pode se manifestar como uma única lesão cutânea localizada, geralmente em partes descobertas do corpo. Tem início com uma pápula, caracterizando a leishmaniose cutânea recente (LCR) e, na maioria dos casos, tende a desenvolver uma úlcera, representando a leishmaniose cutânea clássica (LCC). Pacientes com LCR apresentam um elevado número de parasitas na lesão e, frequentemente, não respondem positivamente à terapia padrão, desenvolvendo a lesão mesmo após o tratamento. Objetivo: Descrever de modo comparativo os aspectos histopatológicos na Leishmaniose Cutânea Recente e Leishmaniose Cutânea Clássica. Métodos: Secções histológicas obtidas de biópsias de pele de 15 pacientes com LCR e 28 com LCC, foram coradas em HE e mensuradas as áreas de inflamação e necrose nas diferentes fases da doença. Realizamos imunohistoquímica para marcação de células CD3+, CD4+, CD8+, CD20+, CD68+ e CD138+...

Introduction: Cutaneous leishmaniasis (CL) is the most common clinical form of human leishmaniasis induced by L. braziliensis. It is considered a major health problem in Brazil. Leishmania braziliensis infection induces a large spectrum of lesions that can manifest as one localized skin lesion, usually undressed body parts. It starts with a papule in early cutaneous leishmaniasis (ECL) clinical manifestation and, in most cases, tends to develop an ulcer, in the late cutaneous leishmaniasis (LCL). ECL patients have a high number of parasites in the lesion, and often do not respond to standard therapy, developing the lesion even after treatment. Aim: To describe comparative the histopathological aspects of early cutaneous leishmaniasis compared to late ulcerated cutaneous leishmaniasis. Methods: Histological sections of skin biopsies from 15 ECL patients and 28 LCL, were stained with HE and measured areas of inflammation and necrosis in the different stages of the disease. We performed immunohistochemical for CD3+, CD4+, CD8+, CD20+, CD68+ and CD138+...

Interaction between Paracoccidioides brasiliensis conidia and the coagulation system: involvement of fibrinogen

The infectious process starts with an initial contact between pathogen and host. We have previously demonstrated that Paracoccidioides brasiliensis conidia interact with plasma proteins including fibrinogen, which is considered the major component of the coagulation system. In this study, we evaluated the in vitro capacity of P. brasiliensis conidia to aggregate with plasma proteins and compounds involved in the coagulation system. We assessed the aggregation of P. brasiliensis conidia after incubation with human serum or plasma in the presence or absence of anticoagulants, extracellular matrix (ECM) proteins, metabolic and protein inhibitors, monosaccharides and other compounds. Additionally, prothrombin and partial thromboplastin times were determined after the interaction of P. brasiliensis conidia with human plasma. ECM proteins, monosaccharides and human plasma significantly induced P. brasiliensis conidial aggregation; however, anticoagulants and metabolic and protein inhibitors diminished the aggregation process. The extrinsic coagulation pathway was not affected by the interaction between P. brasiliensis conidia and plasma proteins, while the intrinsic pathway was markedly altered. These results indicate that P. brasiliensis conidia interact with proteins involved in the coagulation system. This interaction may play an important role in the initial inflammatory response, as well as fungal disease progression caused by P. brasiliensis dissemination.

Mecanismos de patogenia en la malaria por Plasmodium falciparum / Pathogenic mechanisms in Plasmodium falciparum malaria

Se presentan los mecanismos patogénicos más conocidos en la infección por Plasmodium falciparum durante la fase eritrocitaria y extraeritrocitaria. La obstrucción vascular, explicada por los fenómenos de secuestro de glóbulos rojos parasitados y la formación de rosetas, mediados por diversos ligandos y receptores endoteliales, además de los procesos inflamatorios instaurados ante la presencia del parásito, son aspectos centrales en la patogenia de la malaria que permiten explicar. A partir de eventos como la lesión y la destrucción de eritrocitos, hepatocitos y células endoteliales, la pérdida de integridad del endotelio y la activación de promotores de daño celular y de apoptosis, se explican alteraciones como el aumento de la permeabilidad vascular, la hipoxia y el metabolismo anaerobio, que conducen tanto a lesiones localizadas en órganos como cerebro y pulmón, como a un estado de acidosis generalizada y falla multisistémica.

The most recognized pathogenic mechanisms of the infection with Plasmodium falciparum, during both the erythrocytic and exo-erithrocytic stages are presented. Vascular obstruction explained by the sequestration of parasitized red blood cells and erythrocyte rosetting, mediated by different endothelial ligands and receptors, in addition to the inflammatory processes induced by the presence of the parasite, are central aspects in the pathogenesis of malaria that explain the processes of damage, dysfunction and cell death in various organs. Alterations such as increased vascular permeability, hypoxia and anaerobic metabolism leading to localized lesions in organs such as brain and lung, as well as to a generalized acidotic state with multisystem failure can be explained by events such as the injury and destruction of erythrocytes, hepatocytes and endothelial cells, the loss of endothelial integrity, and the activation of cell damage and apoptosis promoters.

Systemic inflammatory response indicators in rabbits (Oryctolagus cuniculus) experimentally infected with sporulated oocysts of Eimeria stiedai (Apicomplexa: Eimeriidae) / Indicadores da resposta inflamatória sistêmica em coelhos (Oryctolagus cuniculus) infectados experimentalmente com oocistos esporulados de Eimeria stiedai (Apicomplexa: Eimeriidae)

Hemograms and acute-phase proteins in adult male New Zealand White rabbits that had been experimentally infected orally with sporulated oocysts of Eimeria stiedai were evaluated over a 28-day period. Fifty animals were used, divided into two groups: group A infected with 1 × 10(4) sporulated oocysts of E. stiedai and group B inoculated with distilled water. On the seventh day after infection, the infected animals presented anemia and leukocytosis with neutrophilia and monocytosis. Protein fractionation by means of electrophoresis identified 19 acute-phase proteins with molecular weights ranging from 24 to 238 kD. Ceruloplasmin, transferrin and haptoglobin showed high levels on the seventh day after infection, with gradual increases in their concentrations until the end of the experimental period. Thus, from the data of the present study, E. stiedai is considered to be a pyogenic etiological agent for which the infection level can be monitored through the leukocyte count and serum concentrations of ceruloplasmin, transferrin and haptoglobin, and these can be recommended as complementary tests.

O hemograma e proteínas de fase aguda foram avaliados durante 28 dias em coelhos adultos, machos, raça branco Nova Zelândia, infectados experimentalmente, via oral, com oocistos esporulados de Eimeria stiedai. Foram usados 50 animais distribuídos em dois grupos: grupo A infectado com 1 × 10(4) oocistos esporulados de E. stiedai e grupo B inoculado com água destilada. No 7º dia após a infecção (dpi), os animais infectados tiveram anemia, leucocitose com neutrofilia e monocitose. O método de fracionamento de proteínas por eletroforese identificou 19 proteínas de fase aguda com pesos moleculares que variaram entre 24 e 238 kD. A ceruloplasmina, transferrina e haptoglobina tiveram níveis elevados no 7° dpi com aumento progressivo de suas concentrações até o término do período experimental. Desta forma, considerando-se os dados encontrados no presente estudo, E. stiedai é considerado um agente etiológico piogênico que pode ter sua infecção monitorada por determinação do leucograma e das concentrações séricas de ceruloplasmina, transferrina e haptoglobina, podendo ser estes recomendados como exames complementares.

Trypanosoma cruzi: blood parasitism kinetics and their correlation with heart parasitism intensity during long-term infection of Beagle dogs

The goals of the present study were to evaluate the kinetics of blood parasitism by examination of fresh blood, blood culture (BC) and PCR assays and their correlation with heart parasitism during two years of infection in Beagle dogs inoculated with the Be-78, Y and ABC Trypanosoma cruzi strains. Our results showed that the parasite or its kDNA is easily detected during the acute phase in all infected animals. On the other hand, a reduced number of positive tests were verified during the chronic phase of the infection. The frequency of positive tests was correlated with T. cruzi strain. The percentage of positive BC and blood PCR performed in samples from animals inoculated with Be-78 and ABC strains were similar and significantly larger in relation to animals infected with the Y strain.Comparison of the positivity of PCR tests performed using blood and heart tissue samples obtained two years after infection showed two different patterns associated with the inoculated T. cruzi strain: (1) high PCR positivity for both blood and tissue was observed in animals infected with Be-78 or ABC strains; (2) lower and higher PCR positivity for the blood and tissue, respectively, was detected in animals infected with Y strains. These data suggest that the sensitivity of BC and blood PCR was T. cruzi strain dependent and, in contrast, the heart tissue PCR revealed higher sensitivity regardless of the parasite stock.

Trypanosoma cruzi high infectivity in vitro is related to cardiac lesions during long-term infection in Beagledogs

Trypanosoma cruzi is a hemoflagelate parasite associated with heart dysfunctions causing serious problems in Central and South America. Beagle dogs develop the symptoms of Chagas disease in humans, and could be an important experimental model for better understanding the immunopathogenic mechanisms involved in the chagasic infection. In the present study we investigated the relation among biological factors inherent to the parasite (trypomastigote polymorphism and in vitro infectivity) and immunoglobulin production, inflammation, and fibrosis in the heart of Beagle dogs infected with either T. cruzi Y or Berenice-78 strains. In vitro infectivity of Vero cells as well as the extension of cardiac lesions in infected Beagle was higher for Y strain when compared to Berenice-78 strain. These data suggested that in vitro infectivity assays may correlate with pathogenicity in vivo. In fact, animals infected with Y strain, which shows prevalence of slender forms and high infectivity in vitro, presented cardiomegaly, inflammation, and fibrosis in heart area. Concerning the immunoglobulin production, no statistically significant difference was observed for IgA, IgM or IgG levels among T. cruzi infected animals. However, IgA together IgM levels have shown to be a good marker for the acute phase of Chagas disease.

Phenotypical characterization of intestinal Schistosoma japonicum granulomas in pigs.

The pig has been proposed as a model for human schistosomiasis japonica and the use of this animal model is increasing. The inflammatory response to schistosome infection in the liver and intestine of the pig shows morphological differences, and only the hepatic granulomas have been phenotypically characterized. The aim of the present study was to phenotypically characterize the cellular inflammatory response in the cecum by immunohistochemistry with particular reference to perioval granulomatous reactions in Schistosoma japonicum infected pigs. Six pigs were exposed to 2000 cercariae and examined 9 weeks post-infection. Three uninfected pigs of the same age served as controls. Exposed pigs developed patent infections with the total number of worms between 6 and 110. Cecal granulomas were dominated by CD3 positive T-lymphocytes and IgG positive plasma cells. Despite the difference in the inflammatory response between the liver and the cecum, the results from this study indicate that the phenotypic cellular composition of cecal granulomas appears similar to what has previously been described in the liver.

Contribuição ao conhecimento da resposta inflamatória do hospedeiro de leishmaniose mucosa, antes e após o tratamento / Contribution to investigation of the host inflammatory response in mucosal leishmaniasis before and after treatment

A Leishmaniose Tegumentar Americana (LTA), doença endêmica no Brasil, é considerada um grande problema de saúde pública. s em biópsias de pacientes com LM. Foram incluídos vinte pacientes, informados e voluntários, com LM, sendo realizadas biópsias da mucosa afetada antes e após a terapêutica específica para leismaniose, além da obtenção de dados clínicos relevantes. Os preparados foram analisados antes e após a terapêutica, avaliando-se a histopatologia do epitélio e da lâmina própria, com comparação semiquantitativa de eventos, quando necessário. Para a comparação de células e citocinas, áreas delimitadas do epitélio e da lâmina nprópria foram quantificadas para o número de células por campo padrão marcadas nas reações imuno-histoquímicas. Pode-se concluir que o tratamento específico é o causador da redução de lesões inflamatórias menos específicas e desaparecimento das formas amastigotas de Leishmania / American Tegumental Leishmaniasis (ATL), An endemic disease in Brazil, is considered to be a major health problem. When the disease is limited to mucosal involvement (mucosal leismaniasis (ML) mainly caused by Leishmania (V.) braziliensis), important morbidity occurs. We may conclude that specific treatment causes a reduction of the less specific inflammatory lesions and the disappearance of the amastigote forms of Leishmania, although the factors related to the pathogenesis of the lesion. A mised Th1 and Th2 response pattern occurs in ML at the tissue level in the lesions before treatment, persisting after treatment although at a lower level, with reduced overall expression of cytokines, but whit persisting expression of IL-4 and IL-10 expression...

Comparación de la reacción inflamatoria causada por el metacestodo de T. solium en músculos y encéfalos de cerdos / Comparison of the inflammatory reaction caused by the metacestode of Taenia solium in brains and muscles of pigs

El objetivo de este estudio fue comparar la reacción inflamatoria que causan los metacestodos de T. solium en tejidos muscular y nervioso de cerdos. Se estudiaron músculos y encéfalos parasitados de cerdos, inoculadoss con huevos de parásito adulto y sacrificados a los 70 y 210 días posinoculación. Los resultados demuestran que las larvas alojadas en el tejido muscular causan una respuesta inflmatoria más severa que las localizadas en el encéfalo. El análisis estadístico Kruskal-Wallis y Quade de los resultados, indican una diferencia altamente significativa (p=3.8 E-0.8) con lesiones más acentudas en el tejido muscular

Olho inflamado no pós-operatório de catarata / Inflamed eyes on postoperative of cataract

As inflamaçöes pós operatórias säo muito frequentes e atualmente há uma tendência em identificar as mesmas como infecçäo. A infecçäo por microorganismos pouco virulentos como Propionebacterium acnes ou o Estafilococo eipidermidis pode produzir uma inflamaçäo lenta cujo aparecimento pode se dar até 36 meses após a cirurgia. Na presença de inflamaçäo pós-operatória recomenda-se o exame clínico que deve identificar uma uveite granulomatosa com ou sem hipópion e uma placa branca sobre a lente intra-ocular, e os exames laboratoriais com meios anaeróbios. O tratamento deve ser prolongado para evitar as recidivas que säo comuns

Pathophysiology of malaria.

The pathophysiology of malaria infection is presented from animal studies and the various manifestations occurring in human cases. Maegraith (1974) proposed the concept of a chain reaction of physiological processes that leads to the disease following malarial infection. It may be seen that the malaria parasites first damage the infected red blood cells directly and then initiate a chain reaction of nonspecific inflammatory processes and later on immunological responses aggravating further the inflammatory reactions. Because of ther interdependence in nature of these changes as suggested by Maegraith in 1977 it is usually difficult to clearly identify these three mechanisms.