V. Amato Neto

Interstitial nephritis in human kala-azar☆

Little is known about renal alterations in kala-azar. The renal histopathology of 21 patients admitted to hospital in São Paulo, Brazil, during the period 1960 through 1981 who either died or had a renal biopsy (two cases) is presented. All the specimens showed oedema and diffuse interstitial inflammatory infiltrate of lymphocytes and plasma cells with more compact foci of cells in some areas. In general, glomeruli did not show any important alterations. These aspects were interpreted as acute interstitial nephritis aetiologically related to later phase kala-azar. This interstitial alteration does not usually seem to determine any clinical manifestations. However, it seems that moderate and severe cortical intersitial damage contribute to the onset of renal insufficiency when severe clinical complications occur. The precise mechanisms of this lesion need further investigation since the aetiological agents have not been seen causing the damage locally.

Comprometimento da medula óssea e eosinofilia na paracoccidioidomicose

Sao descritos 3 casos de paracoccidioidomicose com a forma aguda da doenca, nos quais formas leveduriformes de Paracoccidioides brasiliensis foram visualizadas ao exame direto de medula ossea, sendo a cultura tambem positiva em um caso. Salienta-se o acometimento do sistema fagocitico-mononuclear e a ausencia de resposta as provas cutâneas de hipersensibilidade tardia a antigenos microbianos e de P. brasiliensis em todos, bem como a gravidade do quadro clinico e lesoes osseas generalizadas em um caso, com 20.260 eosinofilos/mm3 no sangue periferico. Os autores discutem o possivel papel do eosinofilo na interacao hospedeiro-parasita na paracoccidioidomicose, sugerindo que a ativacao de subpopulacao TH 2 e o aumento de secrecao de IL 5 e de GM-CSF possam estar relacionados a grande eosinofilia presente no caso mais grave

Alteraçöes hematológicas na leptospirose

30 cases of leptospirosis admitted to the Clinica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo were studied for blood count alterations. 16 patients (53.3%) had a normal white blood cell count at the moment of admission. 12 patients (40%) presented a high white blood cell count and 2 (6.6%) had a low count. 29 patients (96.6%) had a high proportion of neutrophils and 25 patients (83.3%) presented a high number of immature forms. 24 patients had anemia. Thrombocytopenia was present in 26 patients (86.6%). The most characteristic changes found in bone marrow aspirate were the alterations of M:E ratio (myeloid-erythroid ratio) due to relative and/or absolute hyperplasia of the myeloid series, and/or relative and/or absolute hypoplasia of the erythroid series; erythropoiesis was predominantly micro-erythroblastic in many patients; mild to moderate plasmocytosis was found; and, regarding the interstitial series, increased macrophagic activity was noted. There was no direct correlation between the number of megakaryocytes and the blood platelet count, but there was a direct correlation between the bone marrow platelet production and blood platelet count. We believe that it is very difficult to have a good idea of the dynamic mechanisms that lead to medullar platelet production in the presence of platelet consumption, through a random test of the bone marrow.

The detection of Trypanosoma cruzi in Triatoma infestans: comparison of a PCR-based assay with microscopical examination.

The laboratory diagnosis of human American trypanosomiasis (Chagas disease) is currently usually based on serology or the detection of a Trypanosoma cruzi parasitaemia (Maldonado et al., 2004). Unfortunately, most of the serological methods perform poorly when used to detect the re-activation of infections, and are therefore not recommended for determining post-treatment cure (PortelaLindoso and Shikanai-Yasuda, 2003). Parasitaemia can be detected by the direct microscopical examination of samples of blood or buffy coats, haemoculture or xenodiagnosis. Although xenodiagnosis remains the ‘gold standard’, this technique requires expertise and is both cumbersome and time-consuming, often requiring 30–60 days to yield a final result. Despite these drawbacks, xenodiagnosis is indicated in the acute phase of disease or during possible reactivation, whenever the other techniques give negative results (Luquetti and Rassi, 2000). Romaña and Briones (1954) found that infections could sometimes be detected in triatomine bugs fed on acute cases of Chagas disease as early as 6 days post-feed. In the last decade, the use of PCR to detect the DNA of Try. cruzi in faecal samples collected from bugs used in xenodiagnosis has not only increased the sensitivity of the diagnosis but also shortened the time needed to obtain a useful result (Russomando et al., 1996; ShikanaiYasuda et al., 1996). The aim of the present study was to explore and compare the potential usefulness of PCR and direct microscopical examination for detecting Try. cruzi infection in bugs used for xenodiagnosis. Most (220) of the 275 bugs used — thirdand fourth-instar, laboratoryreared Triatoma infestans — were fed on BALB/c mice that had been experimentally infected with the Y strain of Try. cruzi, while the mice were in the acute phase of disease and had low parasitaemias (of approximately 10 parasites/ml blood). The aim of using mammalian hosts with low parasitaemias was to mimic the situation found, during re-activation of Chagas disease, in immunosuppressed heart-transplant patients. The other 55 bugs were fed on uninfected mice, as negative controls. Digestive-tract samples (faeces or abdominal contents) were collected from 25 bugs (20 that had fed on infected mice and five of the negative controls) 1, 2, 3, 4, 5, 10, 15, 20, 25, 30 and 60 days post-feed, with different bugs being used at each timepoint. Each sample was split into two aliquots. A subsample (2–10 ml) of one aliquot was mixed with one to five volumes of 0.9% NaCl solution and then checked by microscopy (at 6400, as a wet smear), while the same volume of the other aliquot was checked by PCR (see below). The primers used in the PCR — F2 (59TGC ACT CGG CTG ATC GTT TTC GAG-39) and B3 (59-AGG GTT GTT TGG TGT CCA GTG TGTG-39), both produced by Integrated DNA Technologies (Belo Horizonte, Brazil) — were designed to produce a 144-bp amplicon from the TCZ repetitive sequence of Try. cruzi (Moser et al., 1989). Genomic DNA was extracted, from a mixture of a digestive-tract aliquot Annals of Tropical Medicine & Parasitology, Vol. 101, No. 5, 461–465 (2007)

Estudo sobre a eventual utilidade de raios gama na profilaxia da malária transmissível por transfusão de sangue

This study was carried out to evaluate the fortuitons advantage of using gamma irradiation in the prophylaxis of transmissible malaria by blood transfusion, with mice as the experimental model. In the first step, when the infected blood with Plasmodium berghei was submitted to 2,500 rad and 5,000 rad, with or without metronidazol, there was no success, because the animals presented parasitaemia and died after inoculation of irradiated blood. However, there was partial success in the second step, when the infected blood received 10,000 and 15,000 rad, and was inoculated in mice, which showed infection, and presented a survival rate of 20% and 40%, respectively, with later negativation of blood infected by P. berghei.This study was carried out to evaluate the fortuitons advantage of using gamma irradiation in the prophylaxis of transmissible malaria by blood transfusion, with mice as the experimental model. In the first step, when the infected blood with Plasmodium berghei was submitted to 2,500rad and 5,000rad, with or without metronidazol, there was no success, because the animals presented parasitaemia and died after inoculation of irradiated blood. However, there was partial success in the second step, when the infected blood received 10,000 and 15,000rad, and was inoculated in mice, which showed infection, and presented a survival rate of 20% and 40%, respectively, with later negativation of blood infected by P. berghei.This study was carried out to evaluate the fortuitons advantage of using gamma irradiation in the prophylaxis of transmissible malaria by blood transfusion, with mice as the experimental model. In the first step, when the infected blood with Plasmodium berghei was submitted to 2,500rad and 5,000rad, with or without metronidazol, there was no success, because the animals presented parasitaemia and died after inoculation of irradiated blood. However, there was partial success in the second step, when the infected blood received 10,000 and 15,000rad, and was inoculated in mice, which showed infection, and presented a survival rate of 20% and 40%, respectively, with later negativation of blood infected by P. berghei.

Infecção por clonorchis sinensis em imigrantes asiáticos no Brasil: tratamento com praziquantel

Fifteen adult patients with assymptomatic infection due to Clonorchis sinensis, diagnosed by coprological examination, were studied. They all came from Asia (twelve from Taiwan, two from South Korea and one from Hong Kong) and were examined at the Adolfo Lutz Institute and the Department of Infectious Diseases, School of Medicine, University of São Paulo, in São Paulo, Brazil. Six patients were women and nine men. All studied patients were admitted to hospital and treated with praziquantel (60 mg/kg). Previous to treatment and on the 15th, 30th and 60th days after praziquantel administration, patients were submitted to quantitative stool examinations, according to Kato-Katzs technique and to hematological and biochemical serum analysis. After a 60 day follow-up nine patients (60%) were negative for C. sinensis eggs in stools. Those not cured after praziquantel administration (six patients, 40%) revealed a sharp decline in faecal elimination of C. sinensis eggs.Estudaram-se quinze pacientes com infeccao assintomatica por Clonorchis sinensis, revelada atraves de exame parasitologico de fezes. Todos eram de origem asiatica e procuraram o Laboratorio Central do Instituto Adolfo Lutz para se submeterem a exames laboratoriais necessarios a regularizacao de sua situacao, face a nova legislacao sobre imigrantes. Eram todos individuos adultos, seis pertencendo ao sexo feminino e nove ao masculino. Os quinze pacientes com clonorquiase foram internados no Hospital das Clinicas da FMUSP e tratados com Praziquantel, na dosagem de 60 mg/kg de peso corporal, dividida em duas tomadas. Foram realizados exames coprologicos quantitativos (metodo de Kato-Katz), antes do tratamento especifico e no 15o, 30o e 60o dias apos a terapeutica. Na ultima avaliacao (60? dia apos terapeutica), em nove pacientes (60,0%) nao se encontraram ovos do trematodeo nas fezes e nos seis (40,0%), que continuavam eliminando ovos, notou-se reducao na quantidade eliminada (superior a 90% em cinco e a 30% no paciente restante). Os pacientes foram tambem submetidos a exames subsidiarios, para avaliacao do estado geral e funcao hepatica, antes da administracao de Praziquantel e, posteriormente, no seguimento ambulatorial. A medicacao foi relativamente bem tolerada pelos pacientes, verificando-se a ocorrencia de efeitos colaterais representados por nauseas e vomitos (dois casos), vertigens e tonturas (dois casos), epigastralgia (dois casos) e diarreia no 3? dia apos tratamento (um caso).

In vitro action of some disinfectants on Paracoccidioides brasiliensis yeast forms

The fungicidal action of sodium hypochlorite (0.3, 1, 2.5, 5 and 10%); formaldehyde (2, 5, and 10%); and ethyl alcohol (70%) on yeast forms of Paracoccidioides brasiliensis Pb 18 and a newly-isolated Goiana strain was described. Contact between the fungus and the disinfectants was maintained for 1, 2, 24, 48 and 72 hours at room temperature. Viability was evaluated by the fluorescein diacetate-ethidium bromide treatment, culture in solid and liquid media (36 degrees C and 26 degrees C); yeast to mycelial germination at room temperature; and radiometric study of metabolic activity. All concentrations of disinfectants were found to be effective in inactivating Pb 18 and Goiana strains, except for the 1-hour contact with 2% formaldehyde, in which fluorescein diacetate-ethidium bromide treatment was found to reveal 40 and 27% of viable cells, respectively. The yeast to mycelial germination method was considered to reveal faster and similar results as compared to culture in solid and liquid media.

Attempted specific treatment, using ticlopidine, of patients in the chronic phase of Chagas' disease.

In a previous study, ticlopidine decreased the parasitemy and mortality of mice infected by Trypanosoma cruzi. Therefore, this drug was administered to 12 patients with Chagas’ disease, in the chronic phase. For 90 days, 150, 200 or 250mg were utilized according to whether the recipients were children, adolescents or adults, respectively. A fully unsuccessful outcome was documented, both sorologically as well as parasitologically. Key-words: Chronic phase of Chagas’ disease. Ticlopidine. Specific treatment. Faculdade de Medicina da Universidade Federal de Goiás e Hospital “São Salvador”, Goiânia, GO, Brasil. Endereço para correspondência: Dr. Anis Rassi. Av. A 333, Setor Oeste, 74110-020 Goiânia, GO, Brasil. Fax: 55 62 281-8097. Recebido para publicação em 30/8/99. Para o tratamento específico da infecção humana devida ao Trypanosoma cruzi contamos atualmente com o benznidazol e com o nifurtimox, cujos resultados ainda deixam a desejar, seja pelo grau de eficácia, seja pela ocorrência de efeitos colaterais, às vezes motivadores de interrupção do emprego dos mesmos. Há, então, necessidade de progressos, sobretudo agora, quando se concede proeminência à participação do parasita no contexto das múltiplas hipóteses patogenéticas concernentes à doença de Chagas. Em virtude do exposto, julgamos adequado efetuar observação de caráter terapêutico, usando ticlopidina, em virtude de interesse por parte de instituições francesas (Sanofi Recherche e Institut National de la Santé et de la Recherche, Médicale – INSERM), tendo Kieffer G, Tobelem G e Degos L participado como assessores científicos, que referiram resultados satisfatórios decorrentes de investigação experimental em camundongos C3H/HeJ, infectados por meio de inoculação da cepa CL do T. cruzi. Houve diminuição da mortalidade e da parasitemia, enquanto que todos os animais do grupo utilizado como controle morreram. O fármaco foi administrado no decurso de 21 dias. Para explicar a atividade antiparasitária admitiu-se que tem lugar efeito inibitório do composto na ligação da fibronectina ao protozoário.