Cytomorphology and immunocytochemistry in the diagnosis of non-Hodgkin lymphomas

1. Lymph node aspirates from 17 patients with an initial cytologic diagnosis of lymphoma (11 cases) or with suspected lymphoma (6 cases) were studied by immunocytochemistry, which led to a final diagnosis. Immunocytochemical staining demonstrated a B-cell phenotype in 10 cases, one case of anaplastic large cell Ki-1+ lymphoma, one lymphoblastic lymphoma negative for B and T cell markers, one large-cell unclassified lymphoma, and one inconclusive case. Three of the cases with suspected lymphoma were diagnosed as reactive lymphadenitis. 2. Combined cytomorphology and cytochemistry permitted a conclusive diagnosis in 13 out of 14 cases of lymphoma. Histology and immunohistochemistry confirmed the cytologic diagnosis. The inconclusive case was diagnosed as a T pleomorphic, small-cell lymphoma by histology. 3. The accuracy of cytomorphology associated with immunocytochemistry is high. However, the diagnosis of low-grade lymphomas, especially of a T phenotype may be difficult.

Parasite and egg burden, hepatic collagen and histologic pattern of liver granulomas in selection III high and low antibody responder mice infected with Schistosoma mansoni

Selection III mice have particular immunological characteristics: they are high (H III) or low (L III) antibody producer animals, yet both lines display similar T cell responses and macrophage activities. We submittedthese mice to infection with Schistosoma mansoni to assess in vivo parasite and egg burden, hepatic collagen and cellular composition of granulomas in both lines. Titration of anti-Schistosoma IgG by ELISA showed remarkably higher values inH III line, at both studied periods (8th and 12th weeks post-infection). Nevertheless, the number of adult worms recovered from the portal system was similar inboth lines, being not associated with anti-Schistosoma antibody levels. There isan increase in hepatic collagen from the 8th to the 12th weeks post-infection, which is paralleled by an increase in the number of eggs in the liver. This association apparently occurs at the same radio in H III and L III animals. The most important difference found between the two lines was the outstanding contrast interms of volume and eosinophil counts in the granulomas, with lesions from H IIImice clearly being larger and containing more of these cells than LIII lesions

The subclinical form of experimental visceral leishmaniasis in dogs

Pathological aspects of a subclinical form of experimental canine leishmaniasis is reported here for the first time. Fifteen mongrel dogs were used in the present study. Eight dogs were infected and seven were used as control. Four of the control dogs were inoculated with spleen cells from non-infected hamsters. The eight mongrel dogs inoculated intravenously with amastigotes forms of Leishmania chagasi envolved for periods as long as 25 months without any clinical characteristic sign of classical Visceral Leishmaniasis (VL). Most of the laboratory test results were compatible to those of the seven control animals but culture of bone marrow aspirated material and serologic testing (IIF) demonstrated or provided evidence that the animals were infected. The most important and predominant histopathological lesion in infected animals were epitheloid granulomas presented in the liver, spleen, adrenal gland and lung of some animals. Channels containing erythrocytes in some granulomas of the liver suggeste that these granulomas are formed inside sinusoidal capillaries. Despite the animals were proved to be infected and presented characteristic histologic lesions, they did not present external signs of disease. The granulomatous aspect of the lesions indicates a good immunologic reactivity and suggest that a host-parasite equilibrium does exist in the dog experimental model

Evaluation of spleen cell population and effect of splenectomy on granuloma modulation in BALB/c mice infected with Schistosoma mansoni

A kinetic study of the cells present in the spleen of BALB/c mice infected with Schistosoma mansoni was carried out. The lymphocytes were evaluated phenotypically with monoclonal antibodies and the effect of splenectomy on the modulation of periovular granuloma was also investigated. The infected mice had proportional increases in the numbers of neutophils, plasma cells, macrophages and eosinophils in the spleen. The largest number of neutrophil, plasma cells and macrophage were found between the 8th and the 12th week of infection, while the amount of eosinophils were higher later on, around the 20th week. The lymphocytes phenotipically characterized as Thy 1.2, Lyt 1.2 (CD4) increased mildly in proportional numbers. However, the percentage of lymphocytes with the Lyt 2.2 (CD8) phenotype, which is characteristic of supressor and cytotoxic T cells, increased significantly with the progress of the disease. The numbers of B lymphocytes, which comprise 50% of the mononuclear cells present in the spleen, increased significantly till the 16th week they began to decrease. The mean diameters of periovular granulomas were comparatively similar in both experimental groups (splenectomized and non-splenectomized mice). However, the evolutive types of granuloma (exudative, intermediate and fibrous) in splenectomized mice were proprtionally different from those of non splenectomized mice in the 16th and 24th week of infection. It is inferred that lymphonodes or other secondary lymphoide organs, in the abscence of the spleen, assume a modulating action on periovular granulomas, although the evolution of the granulomas is somehow delayed in splenectomized mice

Demostracion de la infeccion placentaria por T. Cruzi a traves de la tecnica de inmunoperoxidasa / Demostration of transplacental infections for by T. cruzi inmunoperoxidease technique

Los autores en el presente trabajo, muestran la utilidad y especificidad de la tecnica de la inmuno-peroxidasa aplicada para la identificacion del T. Cruzi y sus formas degeneradas (exoantigenos). Tecnicas realizadas en cortes de tejido de placenta, cordon y membrana incluidos en parafina y procedentes de madres con infeccion chagasica cronica

Natural infection of the opossum Didelphis albiventris (Marsupialia, Didelphidae) with Leishmania donovani, in Brazil

Um gambá, Didelphis albiventris, de Jacobina, Bahia, foi encontrado com infecçäo natural pela Leishmania donovani, sendo o primeiro mamífero silvestre näo-canídeo a ser achado com o agente do calazar nas Américas

Holochilus brasiliensis nanus Thomas, 1897. Sugestao de modelo experimental para filariose, leishmaniose e esquistossomose. / Holochilus brasiliensis nanus Thomas, 1897. Suggestion of an experimental model for filariasis, leishmaniasis and schistosomiasis

Roedores silvestres, classificados como Holochilus brasiliensis nanus Thomas, 1897, foram capturados na cidade de Sao Bento, pertencente a Regiao da Baixada, do Estado do Maranhao, Brasil, naturalmente infectados com formas adultas de filaria, na cavidade peritoneal, e microfilarias sanguineas, assim como, com esquistossoma mansoni (vermes adultos e granulomas periovulares hepaticos; intestinais; pulmonares; esplenicos e pancreaticos). Animais nascidos em Bioterio, descendentes de Holochilus da Regiao da Baixada, foram infectados experimentalmente com Leishmania m. amazonensis e Schistosoma mansoni. Em observacoes semanais, foram encontradas lesoes teciduais, semelhantes as que se desenvolvem em hamsters infectados com Leishmania, e hipergamaglobulinemia. Nos esquistossomoticos, foram constatadas hipergamaglobulinemia e reacoes granulomatosas similares as encontradas nos animais infectados naturalmente. Foram observadas, tambem, lesoes hepatica graves, semelhantes as encontradas na esquistossomose humana. Estes achados sugerem a utilizacao do Holochilus b. nanus como modelo experimental destas tres doencas tropicais

Patogenia da leishmaniose cutanea experimental. A importancia da necrose na eliminacao dos parasitos das lesoes. / Pathogeny to experimental cutaneous leishmaniasis. The importance of necrosis in the elimination of parasites of the lesions

Um estudo histopatologico e ultraestrutural das lesoes da leishmaniose cutanea causada pela Leishmania mexicana amazonensis em duas cepas isogenicas de camundongo uma susceptivel (Balb/c) e outra resistente (A/J), demonstrou que os amastigotas ficavam bem presevados nos vacuolos parasitoforos dos macrofagos, igualmente em ambas as cepas. A reacao de imunofluorescencia revelou antigenos parasitarios no interior e na membrana dos macrofagos de maneira identica para ambas as cepas.A diferenca ocorria quando os macrofagos apareciam destruidos e as leishmanias ficavam livres ou fagocitadas por polimorfonucleares, neutrofilos e eosinofilos. Estes parasitos exibiam entao graus variaveis de nitidos alteracoes degenerativas no camundongo resistence, a necrose, de tipo caseoso ou fibrinoide, era mais disseminada e mais frequente que no animal susceptivel Os achados observados indicaram que as leishmanias nao sao destruidas no interior dos macrofagos e sim foram deles especialmente quando fagocitadas por leucocitos polimorfonucleares. A necrose apareceu como o mecanismo mais saliente atraves do qual o hospedeiro elimina os parasitos das lesoes, sendo a mesma um aspecto importante da reacao de hipersensibilidade tardia que ocorre nos animais resistentes

Granuloma hialino do pulmao e tiroidite de Riedel. Uma associacao sugestiva da sindrome de fibrosclerose multifocal. / Pulmonary hyalinizing granuloma and Riedel's thyroiditis.An association siggesting a multifocal fibroclerotic syndrome

Granuloma hialino de pulmao (GHP) e uma lesao com alguma peculiaridade histopatologica e envolve problemas de diagnostico diferencial com nodulos pulmonares perifericos. Nos estudamos um paciente masculino de 48 anos de idade, com longa historia de nervosismo e fadiga, intolerancia ao calor e aumento de tiroide. Todos os exames de funcao tireoidiana eram normais, com cintilografia com captacao apenas no polo superior do lobo direito da glandula. Foi realizada tireoidectomia total e a glandula achava-se substituida por tecido fibroso colageno denso. Havia tres nodulos com limites definidos no pulmao e o exame microscopico revelou tecido fibroso denso hialinizado, formando feixes enovelados, sem necrose. Coloracao para colageno foram positivas e para amiloide, negativas. Os vasos estavam parcialmente obliterados e havia areas de condensacao de fibras elasticas. Algumas anormalidades imunologicas foram vistas, sugerindo um aumento do numero de linfocitos ativados. Alem disso, a associacao do GHP em sete pacientes (adicionando-se o caso presente), pode indicar um mecanismo sistemico da doenca, com uma possivel base imunologica

Immunopathology of Schistosoma mansoni infection in rabbits. (A preliminary report).

Cinco coelhos infectados experimentalmente pelo Schistosoma mansoni exibiram acentuada resistencia, a qual esteve refletida na baixa recuperacao dos vermes e na escassa producao de ovos. As lesoes histopatologicas se limitaram a focos esparsos de infiltracao eosinofila em torno de ovos imaturos e alguns raros granulomas periovulares. No soro dos coelhos normais (pre-infeccao) foi detectada por imunofluorescencia indireta a presenca de anticorpos contra as estruturas ovulares e dos vermes adultos. Estes anticorpos se tornaram mais evidentes apos a infeccao pelo S. mansoni. Os achados deste estudo preliminar acentuam as peculiaridades da imunopatologia da esquistossomose no coelho