RESUMO
A intradermorreaçäo de Montenegro (IRM) é um método de diagnóstico muito utilizado para a Leishmaniose Tegumentar Americana (LTA). Entretanto, säo relativamente poucos os trabalhos a respeito das alteraçöes texturais provocadas pelo antígeno, sobretudo em cäes. Estudou-se a histopatologia da cinética do teste cutâneo de Montenegro em cäes vacinados experimentalmente com vacina antileishmaniose tegumentar americana (vacina anti-LTA) 6, 12, 24, 48 e 72 horas, 7 e 14 dias após a administraçäo do antígeno. O quadro histopatológico geral segue o padräo observado nas inflamaçöes inespecíficas. Nas primeiras 24 horas, observou-se, geralmente, o exsudato menos intenso e predominantemente composto de granulócitos neutrófilos; após 48 e 72 horas, mais acentuado e constituído principalmente de células mononucleares. Aos 7 e 14 dias a reaçäo tendia a ser menos intensa
Assuntos
Animais , Cães , Cinética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Testes IntradérmicosRESUMO
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.
Assuntos
Granuloma/imunologia , Hepatopatias Parasitárias/imunologia , Esquistossomose mansoni/imunologia , Animais , Granuloma/patologia , Hepatopatias Parasitárias/patologia , Masculino , Camundongos , Esquistossomose mansoni/classificação , Esquistossomose mansoni/patologiaRESUMO
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 capacity for modulation of the 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.
Assuntos
Granuloma/parasitologia , Esquistossomose mansoni/tratamento farmacológico , Animais , Feminino , Granuloma/patologia , Fígado/parasitologia , Fígado/patologia , Camundongos , Recidiva , Esquistossomose mansoni/parasitologiaAssuntos
Antígenos de Protozoários/imunologia , Leishmania/imunologia , Adolescente , Animais , Humanos , MasculinoRESUMO
Two cases of ischaemic necrosis of the sigmoid colon (necrotizing colitis) are reported in 2 brothers aged 7 and 4 years, diagnosed within a 10 d interval. The children had bathed in streams suspected to be contaminated by Schistosoma mansoni about 50-60 d before the onset of acute disease. Both patients had been previously exposed to schistosome-infected streams without showing signs or symptoms of infection. Before admission, S. mansoni eggs had not been found in the stool. Both patients presented with an apparently identical, relatively symptomatic clinical course with rapid evolution to an acute abdomen. Laparotomy disclosed, in both patients, extensive necrosis (ischaemic necrotizing colitis of schistosomal aetiology) of about 20 cm in the first child and 8 cm in the second, extending from part of the descending colon to the sigmoid. The patients were successfully operated upon (hemicolectomy plus colostomy). The histopathological findings were similar in both patients. Ischaemic necrosis with complete destruction of the mucosa and part of the submucosa was detected in the first case; in the necrotic areas a few eggs of S. mansoni were seen, with no granulomatous reaction, but surrounded by cell shadows, pycnotic nuclei and amorphous material. Necrosis extended to the muscular layer and serosa, in which schistosome granulomas in the necrotic-exudative phase were seen, as well as diffuse granulocytic exudate and fibrin. Sections of tissue from both patients contained numerous eggs and granulomas all in the same exudative phase in regional lymph nodes and near the thrombotic vessels. After surgery, the 2 patients progressed similarly. About 10 d after hospital discharge, the patients received anti-schistosomal treatment with oxamniquine. No further sign of infection was detected at subsequent recall visits.
Assuntos
Enterocolite Pseudomembranosa/etiologia , Esquistossomose mansoni/complicações , Doença Aguda , Criança , Pré-Escolar , Colo/patologia , Enterocolite Pseudomembranosa/parasitologia , Enterocolite Pseudomembranosa/patologia , Família , Humanos , Linfonodos/patologia , Masculino , Mesentério/patologia , Esquistossomose mansoni/patologiaRESUMO
The Montenegro skin test is widely 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 in dogs. Two intradermal reactions were used in mongrel dogs during a clinical and epidemiological study as a diagnostic method for canine cutaneous leishmaniasis at Virginópolis, Minas Gerais, Brazil. Leishvacin and P10,000G were used as antigens. The inflammatory reaction was more intense and diffuse in dogs tested with P10,000G than Leishvacin.
Assuntos
Antígenos de Protozoários , Leishmania , Leishmaniose Cutânea/veterinária , Testes Cutâneos , Animais , Brasil/epidemiologia , Cães , Leishmania/imunologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/patologiaRESUMO
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.
Assuntos
Hipersensibilidade Tardia/patologia , Leishmaniose/diagnóstico , Testes Cutâneos/métodos , Humanos , Pele/patologiaRESUMO
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 occurrence of regional variations of the anatomo-clinical forms of schistosomiasis.