The absence of eosinophils is associated with early metastatic lesions in Leishmania amazonensis-infected mice

BACKGROUND Eosinophils are granulocytes that rapidly increase frequency in the bloodstream during helminthic infections and allergic responses. They are found in tissue infected by Leishmania during early disease, but their role during infection is not entirely understood. OBJECTIVES We aim to compare the disease due to Leishmania amazonensis in BALB/c and Δdbl-GATA1 mice, which lack eosinophils. METHODS BALB/c and Δdbl-GATA1 mice infected with L. amazonensis were observed for several weeks. The parasite load and dissemination pattern were assessed. FINDINGS The Δdbl-GATA1 mice developed an anticipated dissemination of L. amazonensis and a worsening disease. No differences were found in the lesion development or the parasite load in the footpad among Δdbl-GATA1 mice and BALB/c eight weeks after infection. However, nine weeks after infection, massive growth of metastatic lesions appeared in several parts of the skin in Δdbl-GATA1 mice, weeks earlier than BALB/c. We observed increased parasites in the bloodstream, probably an essential dissemination route. Thirteen weeks after infection, metastatic lesions were found in all Δdbl-GATA1 mice. MAIN CONCLUSION These results suggest a protective role of eosinophils in delaying the disease caused by L. amazonensis, although several limitations of this mice strain must be considered.

Leishmania enriettii visceralises in the trachea, lungs, and spleen of Cavia porcellus

BACKGROUND Leishmania (Mundinia) enriettii is a species commonly found in the guinea pig, Cavia porcellus. Although it is a dermotropic species, there is still an uncertainty regarding its ability to visceralise during Leishmania life cycle. OBJECTIVE Here, we investigated the ability of L. enriettii (strain L88) to visceralise in lungs, trachea, spleen, and liver of C. porcellus, its natural vertebrate host. METHODS Animals were infected sub-cutaneously in the nose and followed for 12 weeks using histological (hematoxilin-eosin) and molecular tools (polymerase chain reaction-restriction fragment length polymorphism - PCR-RFLP). To isolate parasite from C. porcellus, animals were experimentally infected for viscera removal and PCR typing targeting hsp70 gene. FINDINGS Histological analysis revealed intense and diffuse inflammation with the presence of amastigotes in the trachea, lung, and spleen up to 12 weeks post-infection (PI). Molecular analysis of paraffin-embedded tissues detected parasite DNA in the trachea and spleen between the 4th and 8th weeks PI. At the 12th PI, no parasite DNA was detected in any of the organs. To confirm that the spleen could serve as a temporary site for L. enriettii, we performed additional in vivo experiments. During 6th week PI, the parasite was isolated from the spleen confirming previous histopathological and PCR observations. MAIN CONCLUSION Leishmania enriettii (strain L88) was able to visceralise in the trachea, lung, and spleen of C. porcellus.

Schistosoma mansoni granuloma in late evolutive phase, in a case of tumoral form in man / Granuloma equistossomótico em fase evolutiva tardia, em um caso de forma tumoral no homem

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.

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.

Histopathological findings and detection of parasites in the eyes of dogs infected naturally with Leishmania chagasi / Achados histopatológicos e detecção de parasitas nos olhos de cães infectados por Leishmania chagasi

The objective of the present study was to investigate the histopathological alterations and detection of parasites that occur in the eyes of dogs naturally infected with Leishmania chagasi. The eyes of 25 dogs with a positive parasitological and serological exam for L. chagasi were submitted to routine ophthalmic examination. Fragments were obtained from the eyeball and were analyzed by immunohistochemistry and histopathology. Among the structures studied, the conjunctiva of the third eyelid was the tissue most frequently stained for L. chagasi. Histopathological analysis revealed a predominantly mononuclear inflammatory infiltrate whose intensity ranged from discrete to intense in the various ocular structures. Vascular congestion and perivasculitis were also observed. The histopathological alterations that occur in the eyeball of dogs with visceral leishmaniasis might be related to the presence of antibodies.

O objetivo deste trabalho foi estudar as alterações histopatológicas e a detecção do parasito nos olhos de cães naturalmente infectados por Leishmania chagasi. Utilizaram-se os olhos de 25 cães com exame parasitológico e sorológico positivo para Leishmania chagasi. Os animais foram submetidos à semiotécnica oftálmica rotineira. Fragmentos do globo ocular foram coletados e destinados à imunoistoquímica e histopatologia. Entre as estruturas avaliadas, a conjuntiva da terceira pálpebra foi a que mais demonstrou imunomarcação da Leishmania chagasi. Na avaliação histopatológica, foi observado predominantemente infiltrado inflamatório mononuclear, variando de discreto a intenso nas diversas estruturas oculares. Congestão vascular e perivasculite também foram observadas. As alterações histopatológicas do bulbo do olho em cães com leishmaniose visceral podem estar relacionadas à presença do anticorpo.

Forma tumoral da esquistossomose mansoni cerebelar: relato de caso e medida dos granulomas / The tumoral form of cerebellar schistosomiasis: case report and measure of granulomas

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.

Chronic interstitial pneumonitis in dogs naturally infected with Leishmania (Leishmania) chagasi: a histopathological and morphometric study

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

Histopathology and immunocytochemical study of type 3 e and type 4 complement receptors in the liver and spleen of dogs naturally and experimentally infected with Leishmania (Leishmania) chagasi

Os objetivos deste trabalho visaram uma analise comparativa das alteracoes histopatologicas e da expressao de CR3 e CR4 no figado e baco de caes natural e experimentalmente infectados com L. chagasi. As lesoes histopatologicas fundamentais observadas principalmente nos caes naturalmente infectados foram: os granulomas epitelioides hepaticos, a hiperplasia e a hipertrofia das celulas de Kupffer, dos foliculos de Malpighi e das celulas monucleadas da polpa vermelha do baco. Os cortes de figado e baco corados pela tecnica de imunocitoquimica mostraram a presenca dos antigenos CD11b,cCD18 nos animais controles e infectados, sem diferencas qualitativas e quantitativas no figado...

Estudo histopatológico do teste cutâneo em cäes de área endêmica de leishmaniose tegumentar, utilisando dois antígenos: leishvacin e o P10.000G / Comparative histopathologic study of the skin test in dogs from an endemic of area tegumentary leishmaniosis , using two antigens: leishvacin and P10.000G

A intradermorreaçäo de Montenegro, um teste de hipersensibilidade tardia, é um método muito utilizado no diagnóstico auxiliar da leishmaniose tegumentar americana (LTA) humana. Entretanto, säo escassos os relatos a respeito das alteraçöes induzidas experimentalmente pelo teste cutâneo, sobretudo no cäo. Frente a isso, a nível de campo, foram comparados dois testes cutâneos para diagnóstico da leishmaniose tegumentar canina (LTC), utilizando-se o leishvacin e o P10.000G como antígenos. Nos cäes que receberam o P10.000G, constatou-se reaçäo inflamatória mais evidente e difusa que nos testados com o Leishvacin

Chlamydia trachomatis diagnosticada em 100.000 exames citopatológicos cérvico-vaginais, em Belo Horizonte, Minas Gerais / Chlamydia trachomatis diagnosticated in 100,000 cervico-vaginal screening tests realized in Belo Horizonte, Minas Gerais

Em 100.000 exames citológicos cérvico-vaginais efetuados em Belo Horizonte, Minas Gerais, foram encontrados 564 casos de Chlamydia trachomatis (0,564 por cento) no período de 1984 a 1989. A incidência foi baixa no período compreendido entre 1984 e 1986, elevando-se em 1987. Há indícios de declínio da infecçäo, a julgar pelos poucos casos diagnosticados ultimamente pela técnica de Papanicolau. A freqüência da C. trachomatis foi maior na primavera.

Ocorrência de Trichomonas vaginalis em 100.000 exames citopatológicos cérvico-vaginais diagnosticados entre os anos de 1984 a 1989, em Belo Horizonte, Minas Gerais / Incidence of Trichomonas vaginalis among 100.000 citologic screening tests of routine realized in Belo Horizonte, Minas Gerais during the period 1984 to 1989

Foi verificada a incidência de Trichomonas vaginalis em 100.000 exames citopatológicos de rotina realizados no Laboratório Tafuri de Patologia, em Belo Horizonte, Minas Gerais. Foram encontrados 6.238 casos (6,23 por cento) positivos, no per­odo de 1984 a 1989. A maior incidência foi em 1987 (1.380 casos em 17.433 exames), tendo prevalecido no outono (30,86 por cento) em relaçäo às outras estaçöes do ano. A microflora mais comum foi a mista (Doederlin e cocos), seguida pela Gardnerella vaginalis.