Oogram studies in mice infected with Schistosoma mansoni and treated with dexamethasone

Mice infected with about 90 cercariae of Schistosoma mansoni (LE strain) were treated during five consecutive days with dexamethasone (50 mg/Kg, subcutaneously), starting on the 42th day of infection. Groups of five mice were then daily sacrificed from the first day after onset of treatment until the first day after. The perfusion of the portal system was performed and a piece of the intestine was processed for qualitative and quantitative oograms. This treatment carries to larger numbers of eggs in the tissues of treated mice, when compared with untreated groups. No changes were observed in the kinetics of oviposition, as all stages of viable eggs were observed in the tissues of treated and control mice. These data reinforce the hypothesis of a partial blockade of the egg excretion in immunossupressed mice.Camundongos infectados com cerca de 90 cercárias da cepa LE de Schistosoma mansoni foram tratados durante 5 dias consecutivos com dexametasona (50mg/ Kg, subcutaneamente) a partir do 42º dia de infecção. Grupos de cinco camundongos foram sacrificados diariamente após o primeiro dia do início do tratamento até o primeiro dia após o término. A perfusão do sistema porta foi feita e fragmentos do intestino foram processados para a realização de oogramas qualitativos e quantitativos. O tratamento leva a um maior número de ovos nos tecidos dos camundongos tratados, se comparado com os grupos não tratados. Nenhuma mudança foi observada na cinética de oviposição, e ovos viáveis em todos os estádios evolutivos foram observados nos tecidos de camundongos tratados e controles. Estes dados reforçam a hipótese de um bloqueio parcial na saída de ovos dos tecidos do intestino para o lúmem intestinal em camundongos imunossuprimidos

Acute schistosomiasis: clinical, diagnostic and therapeutic features Esquistossomose aguda: aspectos clínicos, diagnósticos e terapêuticos

Three distinct syndromes caused by schistosomiasis have been described: cercarial dermatitis or swimmer's itch, acute schistosomiasis or Katayama fever, and chronic schistosomiasis. Complications of acute schistosomiasis have also been reported. The absence of a serological marker for the acute stage has hindered early diagnosis and treatment. Recently, an ELISA test using KLH (keyhole limpet haemocyanin) as antigen, has proved useful in differentiating acute from chronic schistosomiasis mansoni. Clinical and experimental evidence indicate that steroids act synergistically with schistosomicides in the treatment of Katayama syndrome. In this paper, clinical, diagnostic and therapeutic features of acute schistosomiasis are updated.<br>A esquistossomose apresenta-se clinicamente em três formas distintas: dermatite cercariana, esquistossomose aguda ou febre de Katayama e esquistossomose crônica. Há na literatura relatos de complicações da fase aguda. A ausencia de um marcador sorológico simples e confiável tem dificultado o diagnóstico precoce e, como consequência, o tratamento adequado de pacientes na fase aguda da doença. Recentemente, o teste de ELISA, realizado com o antígeno KLM (hemocianina do caramujo Megathura crenulata), tem se mostrado util na identificação dos pacientes com febre de Katayama. Evidências clínicas e experimentais apontam no sentido de uma ação sinérgica entre os corticosteróides e os esquistossomicidas no tratamento da esquistossomose toxêmica. Neste artigo, alguns aspectos clínicos, diagnósticos e terapêuticos da esquistossomose aguda são atualizados

Functional autoantibodies against G protein-coupled receptors in hepatic and pulmonary hypertensions in human schistosomiasis

INTRODUCTION: Schistosomiasis (SM) is a parasitic disease caused by Schistosoma mansoni. SM causes chronic inflammation induced by parasitic eggs, with collagen/fibrosis deposition in the granuloma process in the liver, spleen, central nervous system, kidneys, and lungs. Pulmonary arterial hypertension (PAH) is a clinical manifestation characterized by high pressure in the pulmonary circulation and right ventricular overload. This study investigated the production of functional autoantibodies (fAABs) against the second loop of the G-protein-coupled receptor (GPCR) in the presence of hepatic and PAH forms of human SM. METHODS: Uninfected and infected individuals presenting acute and chronic manifestations (e.g., hepatointestinal, hepato-splenic without PAH, and hepato-splenic with PAH) of SM were clinically evaluated and their blood was collected to identify fAABs/GPCRs capable of recognizing endothelin 1, angiotensin II, and a-1 adrenergic receptor. Human serum was analyzed in rat cardiomyocytes cultured in the presence of the receptor antagonists urapidil, losartan, and BQ123. RESULTS: The fAABs/GPCRs from chronic hepatic and PAH SM individuals, but not from acute SM individuals, recognized the three receptors. In the presence of the antagonists, there was a reduction in beating rate changes in cultured cardiomyocytes. In addition, binding sites on the extracellular domain functionality of fAABs were identified, and IgG1 and/or IgG3 antibodies were found to be related to fAABs. CONCLUSION: Our data suggest that fAABs against GPCR play an essential role in vascular activity in chronic SM (hepatic and PAH) and might be involved in the development of hypertensive forms of SM

Abdominal ultrasound in the evaluation of fibrosis and portal hypertension in an area of schistosomiasis low endemicity Ultra-sonografia abdominal na avaliação de fibrose e hipertensão portal em área de baixa endemicidade de esquistossomose

This study was undertaken in the municipality of Bananal, São Paulo, an endemic area for schistosomiasis with a prevalence under 10% and low parasite load among infected individuals. Our objective was to identify the clinical forms of schistosomiasis among 109 patients in whom the disease had been diagnosed through direct fecal analysis and who had been medicated with oxamniquine at the time of the Plan for the Intensification of Schistosomiasis Control Actions (1998-2000). These patients were submitted to an abdominal ultrasonography and fecal analysis by Kato-Katz method, four years, on average, after the end of the Plan. Five patients, whose abdominal ultrasound images were compatible with either peripheral or central periportal fibrosis and portal hypertension, were identified. None of the 109 patients presented Schistosoma mansoni eggs at fecal analysis. Ultrasonography is a sensitive, noninvasive diagnostic method that allows a better identification of the extent of liver involvement in schistosomiasis cases.<br>Este estudo desenvolveu-se no município de Bananal, São Paulo, uma área endêmica para esquistossomose com prevalência menor que 10% e baixa carga parasitária nos infectados. Teve como objetivo a identificação de formas clínicas da esquistossomose mansoni através do exame ultra-sonográfico, em 109 pacientes diagnosticados parasitologicamente e medicados com oxamniquine, durante a realização do Plano de Intensificação das Ações de Controle da Esquistossomose mansônica (1998-2000). Foram utilizadas a ultra-sonografia abdominal e exames de fezes (Kato-Katz) realizados após o término do plano, quatro anos em média. Nesta casuística, foram identificados cinco pacientes com imagens ultra-sonográficas abdominais compatíveis com fibrose periportal periférica ou central e hipertensão portal, além da negatividade de todos os exames parasitológicos nos 109 pacientes. A ultra-sonografia, um método de diagnóstico sensível e não invasivo, possibilitou a identificação de casos com comprometimento hepático em uma área de baixa endemicidade para esquistossomose mansoni