Abstract Purpose: To evaluate the most frequent surgical techniques of high-risk colorectal anastomoses in rats. Methods: Wistar rats were enrolled in three different models comprising inflammatory (TNBS enema), vascular (portal vein occlusion) or obstructive (a non-ischemic constricting ring) mechanisms associated with colonic anastomosis that had accomplished after these former lesions. Histological analyses (Hematoxylin and eosin and Picrosirius red) were performed. Results: All anastomoses techniques were associated with risk factors and had complications, mainly anastomotic leakage. In Study 1, the use of a pharmacological agent, trinitrobenzene sulfonic acid (TNBS) mimicked an inflammatory bowel disease such as Crohn’s disease with 50% of anastomosis leakage, the higher percentage among all models tested. In Study 2, after portal ischemia followed by reperfusion it was observed a dense neutrophil infiltrate in the midst of necrotic tissue and fibrin at the anastomotic site and 5 days after the anastomosis, no collagen was produced. In Study 3, 5 days after the mechanical obstruction some denuded areas of epithelium with marked oedema of mucosa and submucosa were seen, at the anastomotic site and anastomosis group showed some reduction of collagen density when compared with Control/Sham group. Conclusion: All the experimental surgical techniques tested in rats were associated with high-risk colorectal anastomoses and were useful to study colonic anastomotic healing and intestinal leakage.

We describe a schistosomal polyp in the anus of a 24-year-old patient, born in Viçosa, State of Minas Gerais, and living in Belo Horizonte, State of Minas Gerais. From 8 to 13 years of age, he swam in the rivers that bathe Viçosa. The histopathological examination has shown a lesion, lined by a keratinized squamous epithelium, ulcerated, with granulomas, centered or not by Schistosoma mansoni egg, laid, in loco, by the female present in the vascular lumen of a vein of the hemorrhoidal plexus. There was also a diffuse, nonspecific inflammation in the dermis. The patient was treated with praziquantel. Four months after the treatment, sigmoidoscopy showed a normal rectal mucosa, and negative oogram and stool tests. Ultrasound of abdomen was normal.

INTRODUÇÃO: Os autores descrevem o granuloma esquistossomótico no homem, na fase crônica tardia, do ponto de vista morfológico e evolutivo. MÉTODOS: O estudo baseou-se na análise histológica de dois fragmentos obtidos de biópsia cirúrgica do peritônio e do intestino grosso de um paciente de 42 anos de idade, com a forma pseudotumoral mimetizando carcinomatose peritoneal associada à forma hepatointestinal da esquistossomose. RESULTADOS: Foram identificados 203 granulomas no pseudotumor e 27 na biópsia intestinal, com aspectos morfológicos semelhantes, a maioria na fase crônica tardia, em cura por fibrose. Foi sugerida nova classificação estrutural para os granulomas: zona 1 (interna), zona 2 (intermediária) e zona 3 (externa). CONCLUSÕES: Considerando o granuloma como um todo, concluímos que, provavelmente, a fibrose é comandada por mecanismos diferentes e independentes nas três zonas do granuloma. A fibrose lamelar na zona 3 parece ser comandada pelas células mesenquimais da matriz (fibroblastos e células mioepiteliais) e pelas células do exsudato inflamatório (linfócitos, plasmócitos, neutrófilos, eosinófilos). A fibrose anular na zona 2, composta por conjuntivo fibroso denso, pouco celular na fase avançada, seria comandada pelas células epitelioides que envolvem a zona 1 nos granulomas recentes. Na zona 1, substituindo a necrose periovular, a neoformação conjuntiva inicialmente frouxa, rendilhada, albergando células estreladas ou com núcleos fusiformes, surge um conjuntivo denso, paucicelular, nodular, provavelmente induzido pelos fibroblastos. Em muitos granulomas falta uma das zonas descritas e o granuloma é representado apenas por duas delas: Z3 e Z2, Z3 e Z1 ou Z2 e Z1 e, no final, por uma cicatriz.

INTRODUCTION: Authors describe human schistosomal granuloma in late chronic phase, from the morphological and evolutionary viewpoints. METHODS: The study was based on a histological analysis of two fragments obtained from a surgical biopsy of peritoneum and large intestine of a 42-year-old patient, with a pseudotumoral form mimicking a peritoneal carcinomatosis associated to the schistosomiasis hepatointestinal form. RESULTS: Two hundred and three granulomas were identified in the pseudotumor and 27 in the intestinal biopsy, with similar morphological features, most in the late chronic phase, in fibrotic healing. A new structural classification was suggested for granulomas: zone 1 (internal), 2 (intermediate) and 3 (external). CONCLUSIONS: Regarding granuloma as a whole, we may conclude that fibrosis is likely to be controlled by different and independent mechanisms in the three zones of the granuloma. Lamellar fibrosis in zone 3 seems to be controlled by matrix mesenchymal cells (fibroblasts and myoepithelial cells) and by inflammatory exudate cells (lymphocytes, plasmocytes, neutrophils, eosinophils). Annular fibrosis in zone 2, comprising a dense fibrous connective tissue, with few cells in the advanced phase, would be controlled by epithelioid cells involving zone 1 in recent granulomas. In zone 1, replacing periovular necrosis, an initialy loose and tracery connective neoformation, housing stellate cells or with fusiform nuclei, a dense paucicellular nodular connctive tissue emerges, probably induced by fibroblasts. In several granulomas, one of the zones is missing and granuloma is represented by two of them: Z3 and Z2, Z3 and Z1 or Z2 and Z1 and, ultimately, by a scar.

Caso raro de forma tumoral da esquistossomose mansoni cerebelar diagnosticada pela biópsia, em um paciente de 15 anos, que apresentou sinais e sintomas neurológicos 60 dias antes da cirurgia. A tomografia computadorizada revelou lesão expansiva, hiperdensa, localizada no cerebelo, sugestiva de glioma. O exame histopatológico mostrou numerosos ovos de S. mansoni envolvidos por reação inflamatória granulomatosa na fase necrótico-exsudativa, confluentes, localizados principalmente na camada interna, granular, do cerebelo, formando pseudotumor no verme cerebelar e hemorragia recente na ponte. Foram medidas as áreas dos granulomas.

An unusual case of the tumoral form of cerebellar Schistosomiasis mansoni, in a 15 year-old male diagnosed by biopsy, with neurological signs and symptoms 60 days prior to surgery. Computerized tomography show a hyperdense expanding lesion located in cerebellum, suggesting glioma. Histopathological examination showed numerous S. mansoni ova involved by granulomatous inflammation in necrotic-exudative phase, located mainly in the internal, granular layer of the cerebellum, creating a pseudotumor in the cerebellar vermis and a recent hemorrhage in the trunk. The areas of granulomas were measured.

Relatamos um caso raro de linfoma maligno não-Hodgkin, nodular e de baixo grau, tipo MALT, com aspecto morfológico e imuno-histoquímico linfoplasmocitóide (classificação de REAL), de imunofenótipo de linfócitos B e monoclonalidade para a cadeia leve de imunoglobulina Kappa, com índice de proliferação < 10% (baixo grau). O tumor era primitivo da dura-máter parietal esquerda, em mulher de 36 anos de idade, cujos sintomas neurológicos surgiram quatro meses antes da cirurgia. Após a cirurgia, foi tratada com quimioterapia e radioterapia, com bom resultado.

We describe a rare case of nodular and low grade non-Hodgkin malignant lymphoma, MALT type, with morphological and immunohistochemical features of lymphoplasmocytic (REAL classification), of immunophenotype of B lymphocytes and detecded monoclonal of immunoglobulin kappa light chains, with low proliferation grade (<10%). The tumor was primitive of the left parietal duramater in a 36 years old woman, who presented neurological clinical symptoms four months before the surgery. After surgery, she was submitted to chemotherapy and radiotherapy with good results.

Neste estudo, foram utilizados dezoito cães naturalmente infectados com Leishmania (Leishmania) chagasi, sem raça e idade definidos, cedidos pelo Centro de Contole de Zoonoses da Cidade de Belo Horizonte. Quatro cães foram utilizados como controle. Durante a necropsia, amostras do pulmão foram coletadas, e imediatamente fixadas em formalina. A histopatologia mostrou principalmente uma pneumonite intersticial crônica, produtiva, difusa e intensa. Os septos inter-alveolares espessados, eram constituídos principalmente por um infiltrado de células inflamatórias, em sua maioria, macrófagos, linfócitos e plasmócitos, além de fibroblastos e fibras colágenas. A análise morfométrica do espessamento septal mostrou diferença significativa entre animais infectados e controle. De fato, a análise morfométrica do colágeno, corado pela prata, confirmou um aumento na deposição de colágeno em todos os animais infectados. O exame parasitológico foi ralizado durante a análise histopatológica, em todos os casos estudados. Contudo neste trabalho, não observamos qualquer correlação entre os achados histopatológicos e morfométricos quando relacionados aos cães em diferentes formas clínicas. Concluímos que as lesões, encontradas nos cães naturalmente infectados, tem correlação com a doença, e que o método de análise morfométrica utilizado apresentou resultados satisfatórios quanto à análise do espessamento septal e ao aumento da deposição de colágeno, confirmando a fibrose.

Eighteen mongrel dogs of unknown age and naturally infected with Leishmania (Leishmania) chagasi, were obtained from the City Hall of Belo Horizonte, Brazil. Four dogs were used as control. Lung samples were obtained and immediately fixed in formalin. The histopathological picture of all lung tissue sections was a chronic and diffuse interstitial pneumonitis. The thickened inter-alveolar septa were characterized by the cellular exudate (mostly macrophages, lymphocytes and plasmocytes) associated with collagen deposition. Morphometric analysis showed greater septal thickness in the infected animals than in controls. In fact, the morphometric study of collagen stained with ammoniac silver confirmed a larger deposition of collagen in the infected animals. The parasitologic method was carried out during the study of the lesions on the slides. However, we did not observe any correlation between the histopathologic and morphometric data and the clinical status of the animals. We conclude that the pulmonary lesions observed in all naturally infected dogs were correlated with the disease and that the morphometric method used was satisfactory for the analysis of septal thickness and of increased collagen deposition, confirming the presence of fibrosis.

No presente estudo, verificou-se o comportamento histopatológico das infecções e reinfecções, homólogas ou heterólogas, das cepas LE (Belo Horizonte, MG) e SJ (São José dos Campos, SP) de Schistosoma mansoni. Confirmou-se uma maior patogenicidade da cepa SJ de S. mansoni. As reinfecções, independentemente de terem sido feitas com a mesma cepa (homóloga) ou cepa diferente da primo infecção (heteróloga) do parasito, mostraram a presença de granulomas típicos da fase aguda. São discutidos os possíveis mecanismos responsáveis pela reagudização da resposta imunopatológica nas reinfecções.

In this study, which was undertaken in relation to the histopathologic behavior of two different strains (LE-Belo Horizonte, MG and SJ - São José dos Campos, SP) in infections and reinfections (homologous or heterologous) with Schistosoma mansoni, the authors confirmed a more accentuated pathogenicity of the SJ strain. All the reinfections showed the presence of typical granulomas of the acute phase, when performed either with the same strain (homologous) or with a different strain (heterologous) of the parasite of the primo infection. The possible mechanisms responsible for reactivation of the immunopathologic response in reinfections are discussed.

Para verificar a capacidade de modulação da resposta granulomatosa na esquistossomose murina, após cura quimioterápica, camundongos previamente infectadosforam curados com oxamniquina (400mg/kg, p. o.) e reinfectados 20 dias após tratamento. O exame histopatológico do fígado dos animais, aos 60 dias após reinfecção, mostrou, na maioria deles, a presença de granulomas nafase produtiva, típicos da fase crônica da doença, pertnitindo a inferência de que a capacidade de modulação da resposta granulomatosa foi mantida, prevenindo assim uma outra fase aguda da doença. Por outro lado, um grupo de camundongos previamente infectados e submetidos a reinfecção mostrou a reagudização da resposta granulomatosa em 50% dos animais. As possíveis implicações destes achados na esquistossomose mansoni humana são discutidas.

Mice previously infected with Schistosoma mansoni, and cured by specific treatment (400mg/kg oxamniquine, p. o.) in the chronic phase of the disease, were reinfected 20 days after treatment to assess their capacityfor modulation ofthe granulomatous response. Histopathologic examination of the animals ' liver, at 60 days after reinfection, evidenced the presence of typical granulomas of the chronic phase in most animals. This infer that the capacity for modulation of the granulomatous response had been maintained, thus preventing a new acute phase of the disease. Conversely, a group of previously infected mice, untreated and submitted to reinfection, showed reactivation of the granulomatous response in 50% of the animals. The possible implications of these findings in human schistosomiasis mansoni are discussed.

A intradermorreação de Montenegro, um teste de hipersensibilidade tardia, é um método muito utilizado no diagnóstico auxiliar da leishmaniose tegumentar americana (LTA) humana. Entretanto, são escassos os relatos a respeito das alterações histológicas induzidas experimentalmente peto teste cutâneo, sobretudo no cão. Frente a isso, a nível de campo, foram comparados dois testes cutâneos para diagnóstico da leishmaniose tegumentar canina (LTC), utilizando-se o LeishvacinR e o P10.000G como antígenos. Nos cães que receberam o PIO.OOOG, constatou-se reação inflamatória mais evidente e difusa que nos testados com o LeishvacinR.

The Montenegro skin test is widefy used as a diagnostic method for American cutaneous leishmaniasis (ACL). However, there is little information about the histological changes that occur after administration of the antigen, especially indogs. Two intra dermal reactions were used in mongrel dogs during a clinical and epidemiolog ical study as a diagnostic method for canine cutaneous leishmaniasis at Virginópolis, Minas Gerais, Brazil. LeishvacinR and P10.000G were used as antigens. The inflammatory reaction was more intense and diffuse in dogs tested with PIO.OOOG than LeishvacinR.

Foi realizado o estudo histológico do material obtido nas biópsias do local de inoculação do antígeno para teste de Montenegro (T.M.) nos seguintes grupos de indivíduos: I) Seis pacientes com leishmaniose cutânea comprovados parasitologicamente, com Montenegro positivo; II) Cinco indivíduos normais, não residentes em zona endêmica, com Montenegro negativo; III) Nove soldados participantes de ensaios clínicos com vacina anti-LTA - MAYRINK e cols. 1979 e que tiveram o TM positivo 35 dias após vacinação. IV) Um último grupo constituído de quatro soldados, também participantes de ensaio clínico com a mesma vacina acima, dois vacinados que não mostraram TM positivo 35 dias após vacinação e dois que receberam placebo. As biópsias foram realizadas 48 hs após a inoculação do antígeno. O material foi fixado em formol à 10% (pH 7.2). Histologicamente, excetivando o grupo II (controle negativo), os grupos I-I1I-IV mostraram diferenças quantitativas no infiltrado mononuclear. Os quadros histológicos de cada grupo são descritos e discutidos.

The Montenegro skin test is widely used as a diagnostic method for American cutaneous leishmaniasis (ACL) but little is known about the histological changes that occur in the skin after administration of the antigen. This report is based on histological studies of biopsied material obtained, from inoculation sites, 48 hours after individuals had been given intradermal injections with a standardized Montenegro antigen. The material examined was obtained from four distinctly different test groups: naturally infected patients with parasitologically proved ACL and with positive Montenegro's reaction; individuals without previous history of ACL and not previously tested with Montenegro antigen; participants in anti-ACL vaccine trials who developed positive reactions to Montenegro antigen after vaccination; other participants in vaccine trials who had negative Montenegro responses after vaccination or had served as controls in the trials. The histological pictures of each group are described and discussed. Histologically, the reactions of vaccinated individuals were indistinguishable from those with naturally acquired infections.

Os autores determinaram o diâmetro médio dos granulomas de fígado de camundongos infectados com cercárias de duas cepas geográficas bem definidas do, Schistosoma mansoni (LE, Belo Horizonte e SJ, São Paulo). No total foram medidos 1.170 granulomas. Os granulomas com 60 dias eram de dimensões maiores do que os de 90 dias. A modulação da resposta imunopatológica foi significativamente mais eficiente na cepa LE e os granulomas, tanto aos 60 como aos 90 dias, da cepa SJ eram significativamente maiores. Os dados obtidos indicam uma maior patogenicidade da cepa SJ. Especula-se se o significado destes achados poderiam, em parte, explicar a ocorrência das variações regionais das formas anatomo-clínicas da esquistossomose.

The authors have determined the mean diameter of granulomas in the liver of mice infected with cercariae from two different and well definite geographic strains of Schistosoma mansoni (LE, Belo Horizonte, MG, and SJ, São José dos Campos, SP). A total of 1,170 granulomas has been measured. Granulomas measured on the 60th day after infection showed larger size than the other ones measured on the 90th day. Modulation of the immunopathologic response was significantly more efficient for the LE strain, whereas the granulomas ( with 60 and 90 days) related to SJ strain were significantly larger. Data suggested a higher pathogenicity for the SJ strain. It is speculated whether these findings could explain, in part, the occurence of regional variations of the anatomo-clinical forms of schistosomiasis.

The post-treatment pulmonary alterations were evaluated in patients (Study 1) and in mice (Study 2) infected with Schistosoma mansoni. Study 1: the patients were examined pre and post-treatment (with ora oxamniquine) and the following exams were performed: sputum for eosinophils and chest x-ray. Study 2: four groups of mice (total = 64) were studied; Group I (infected and treated with oxamniquine); II (infected and not treated); III (not infected and treated) and IV (not infected and not treated). All were x-rayed to check for pulmonary abnormalities pre and post-treatment and lung specimens were studied by optical microscopy and immunofluorescence. We have found abnormalities in the parameters checked in both studies and the results suggest an immunological reaction, probably due to deposition of immune complexes in the lungs, with subsequent activation of the complement system. The experimental study showed that the alterations are not dependent of the presence of eggs and/or worms of S. mansoni in the lungs, thus corroborating the hypothesis of deposition of circulating material.

Camundongos infectados com 60 cercárias de Schistosoma mansoni tomaram-se mais resistentes ao sarcoma 180 na forma de tumor ascítico. A inoculação das células tumorais foi feita no 50º dia de infecção e a evolução do tumor foi acompanhada através dapesagem dos animais com intervalos de 48 horas. Nos camundongos infectados o ganho de peso (formação da ascite) começou mais tarde e foi menor do que nos controles não infectados. Também o número de células tumorais na cavidade peritoneal 72 horas após a implantação do tumor foi menor no grupo infectado. Este aumento de resistência a um tumor transplantávelpossivelmente está relacionado ao efeito de endotoxinas sobre a atividade tumoricida dos macrofagos ativados pela infecção. A imunossupressão induzida pela infecção favorece a proliferação de bactérias da flora endógena aumentando a quantidade de endotoxinas absorvidas pelo intestino.

Mice infected with 60 cercariae of Schistosoma mansoni were more resistant to the sarcoma 180 ascites tumor. Tumor inoculation was performed 50 days after schistosoma infection and the animals were observed and weighed at 48 hours intervals for development and progression of malignancy. In infected mice the weight gain (ascites formation) started later and was shorter than in uninfected Controls. Also, the number of tumor cells into the peritoneal cavity 72h after tumor implantation was shorter in infected group than incontrols. This in creased resistance against a transplantable tumor probably is related to the effect of endotoxin on tumoricidal activity of macrophages activated by the infection. The immunodepression induced by Schistosoma mansoni infection enhances the proliferation of endogenous bacteria increasing the amount of endotoxin absorbed from the gut.