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Une technique d'extraction rapide d'ADN a ete utilisee pour la detection de T. cruzi dans des excrements secs d'insectes obtenus sur papier filtre et analyses par PCR. Cinquante T. infestans ont ete nourris dans des souris Balb/C infectees experimentalement par T. cruzi (haute parasitemie), divises dans cinq groupes de dix triatomines et 100 triatomines ont ete infectees (faible parasitemie) et divises dans cinq groupes de 20 triatomines. Un petit rond de papier filtre a ete analyse par groupe aux premier, second, troisieme, quatrieme et cinquieme jours apres l'infection. L'amplification de la sequence TCZ de T. cruzi a ete positive des le quatrieme jour dans les deux modeles (haute et faible parasitemie). La technique d'extraction d'ADN proposee suivie par PCR est appropriee pour la detection de T. cruzi sur papier filtre et pourrait etre utilisee dans des travaux de terrain.

Chemical methods to sterilize the blood contaminated with trypanozomes were investigated. Safe blood results when gentian violet (0.5 per cent in glucose solution) is added to the blood in a f

Six cases of American Trypanozomiasis transmitted by blood transfusion are studied. In two of them the disease was manifested as an acute infection similar to those acquired by natural way wit

Os microsporídios são implicados em várias manifestações clínicas em pacientes com AIDS; os quadros diarréicos são os mais comuns. O diagnóstico das microsporidioses dependia da microscopia eletrônica para exame de materiais obtidos por procedimentos invasivos. A técnica de coloração tricrômica modificada permite o diagnóstico sem necessidade deste procedimento, através da microscopia óptica. No presente estudo foi aplicado o método de coloração tricrômica em fezes de 62 pacientes com diarréia, infectados pelo HIV ou com AIDS. Das 62 amostras, identificou-se esporos de microsporídios em uma. O trabalho corrobora a presença destes protozoários em nosso meio, associada a quadros de diarréia crônica em pacientes com AIDS e grave comprometimento imunológico; constata que este método de coloração promove satisfatória visualização de esporos de microsporídios em fezes e aponta caminhos para novos estudos. The microsporidia have been involved in several clinical manifestations in patients with AIDS, of whom diarrhoea is the commonest. The diagnosis of microsporidiasis depended on invasive procedures and the identification of the organisms is made by electron microscopy. The modified trichrome staining method allows that the diagnosis be made without such procedures by using light microscopy. In the present work, the modified trchrome method was applied in stools from 62 patients with diarrhoea, who had asymptomatic HIV infection or AIDS. Of the 62 samples analyzed, there was detection of microsporidial spores in one. This work confirms the existence of such protozoans in our patients, associated with manifestations of chronic diarrhoea in patients with AIDS who have severe immunodeficiency and ascertains that this staining method allows satisfactory identification of microsporidia from faeces, as well points out some directions to further studies.

Em modelo experimental, baseado na infecção de ratos pelo Strongyloides venezuelensis, foi avaliada a atividade terapêutica de duas preparações de ivermectina, para usos veterinário e humano. Houve interesse em verificar a efetividade em relação a vermes adultos e formas larvárias. A administração dos fármacos ocorreu sempre por via oral e a posologia correspondeu à dose única de 0,2mg/kg. Considerados os vermes adultos e as formas larvárias, o produto para emprego veterinário propiciou eliminações expressas pelas porcentagens de 98,0% e 84,2%; quanto à outra preparação, as taxas situaram-se em 59,3% e 73,0%, respectivamente. O estudo revelou, então, utilidade do anti-helmíntico quando usada a via oral e, também, mostrou significativa ação sobre as formas larvárias, certamente valiosa quando vigente a modalidade disseminada da estrongiloidíase.Strongyloides venezuelensis experimental infection in rats was treated by two different oral preparations of ivermectin, 0.2mg/kg. One was a human formula used by WHO in the treatment of onchocerciasis; the other was a veterinary preparation. Adult worms and larvae were evaluated. The human formulation cleared both forms in 59.3% (adult worms) and 73.0% (larvae), whereas the veterinary one cleared 98.0% and 84.2%, respectively. The antilarval action is very useful when treating systemic strongyloidiasis

Três cepas do Trypanosoma cruzi foram, isoladas de pacientes com doença de Chagas crônica, receptores de coração por meio de tra?isplante. Houve caracterização delas através de modelo experimental baseado no emprego de camundongos, com avaliação de parasitismo, mortalidade e intensidade da inflamação no coração, além de análise do grau de parasitismo nesse órgão. Como controle, teve lugar comparação com o comportamento da já bem conhecida cepa Y. Ficaram caracterizadas atuações diferentes das cepas, ao serem valorizados os parâmetros citados, sem correlação rigorosa com as evoluções pós-transplantes, que sofrem a influência de vários fatores, entre os quais podem estar particularidades vinculadas ao parasitismo.Three strains of Trypanosoma cruzi were isolated from Chagas' disease patients transplanted for heart failure, after cardiac transplantation, and were studied in an experimental model of Chagas' disease, in mice, with evaluation of parasitic load, mortality and extension of inflammatory infiltrates in the heart. These parameters were compared with the standard strain Y. The strains had differences in the studied parameters, but there was no clear relationship between those and post-transplant evolution of the patients. Probably the clinical response is multifactorial and derives only in part from biological characteristics of the infecting T. cruzi strain, as measured in our model.

Valorizando a sensibilidade do sistema Quantitative Buffy Coat (QBC), documentada em modelo experimental murino, estando os animais com infecção aguda pelo Trypanosoma cruzi houve tentativa de evidenciar esse parasita no sangue periférico de 100 pacientes com doença de Chagas, em fase crônica. Com o emprego desse método, nenhuma positividade ocorreu, evidentemente em virtude das pequenas parasitemias, não reveláveis pela técnica, pelo menos conforme o verificado através da casuística considerada.

Myocarditis is not an uncommon finding in autopsy series of patients with AIDS, although clinically important myocarditis is rarely noted. We describe a 50-year-old woman with AIDS and chronic chagasic megaesophagus, without previous cardiac abnormalities, who experienced reactivation of Chagas' disease, characterized by the finding of Trypanosoma cruzi via direct microscopic examination of the buffy coat, xenodiagnosis, and blood culture ; she developed fatal acute myocarditis. Reactivation of Chagas' disease in patients with AIDS has been reported, but in the great majority of cases it has been associated with central nervous system involvement. In areas where Chagas' disease is endemic, reactivation may occur in patients with AIDS.

Fecal samples from 140 adult stray dogs of Greater São Paulo (São Paulo State, Brazil) were examined for Cyclospora sp oocysts. No cases of infection by this coccidium were detected.

Infections of Plasmodium berghei in mice was stopped by azithromycin which was administered orally in dosages of 100mg/kg, for 28 days. This antibiotic was given since the same day that the animals were infected. The outcome suggests the necessity of more investigations on this antiparasitic activity.

In a previous study, ticlopidine decreased the parasitemia 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 250 mg were utilized according to whether the recipients were children, adolescents or adults, respectively. A fully unsuccessful outcome was documented, both serologically as well as parasitologically.

Patients in the chronic phase of Chagas' disease and receiving corticoid because of concommitant diseases were treated with benznidazole, which was initiated at the same time of the use of corticoid in a group of 12 patients or 15 days afterwards in 6 patients. It has been proved in another paper that in the chronic phase of Chagas' disease corticoid use is associated with increased parasitemia, as evaluated by xenodiagnosis. In this study benznidazole use prevented this increase, and we suggest that in immunocompromised patients with chronic Chagas' disease the use of this drug could be useful.

The efficacy of azithromycin and pyrimethamine in experimental infection of mice with Toxoplasma gondii was tested. Daily dosages of 200 mg/kg and 12.5 mg/kg, respectively, were given orally over a period of ten days. The medications were administered in combination or separately. The combined use of the drugs yielded better results, and a similar investigation using a cystogenic strain of the parasite will be conducted in a future study.

The microsporidia have been involved in several clinical manifestations in patients with AIDS, of whom diarrhoea is the commonest. The diagnosis of microsporidiasis depended on invasive procedures and the identification of the organisms is made by electron microscopy. The modified trichrome staining method allows that the diagnosis be made without such procedures by using light microscopy. In the present work, the modified trchrome method was applied in stools from 62 patients with diarrhoea, who had asymptomatic HIV infection or AIDS. Of the 62 samples analyzed, there was detection of microsporidial spores in one. This work confirms the existence of such protozoans in our patients, associated with manifestations of chronic diarrhoea in patients with AIDS who have severe immunodeficiency and ascertains that this staining method allows satisfactory identification of microsporidia from faeces, as well points out some directions to further studies.

To verify any possibility of the elimination of p24 in feces of Triatoma infestans, p24 being an antigen and one of the markers of HIV infection. The purpose of the study was the evaluation of any risk of contamination by laboratory staff who work with activities related to this particular insect, and also investigate any mechanism that might thus lead to the dissemination of HIV.Triatoma infestans were fed with p24-marked blood from 23 AIDS patients. Twenty-four and 48 hours later, their feces were examined in order to verify the presence of the antigen. The search for p24 was performed by means of the immunoenzymatic technique.No protein 24 was detected in any of the samples. In accordance with the applied methodology, the purpose of showing that the elimination of p24 does not occur, was obtained. Were this question approached in other ways different results might reveal new information in terms of risks of HIV dissemination.

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.

The authors report a case of a 89 years-old woman with mucocutaneous leishmaniasis and previous diabetes mellitus and high blood pressure, who had been treated with allopurinol for 10 months without healing of lesions. Afterwards, she has been treated with meglumine antimonate, "glucantime" for 4 days, with a total dose 2,380 mg of Sbv, but developed cardiac side effects and hypokalemia, hence the treatment was withdrawn. However, this patient developed total clinical regression of lesions, in spite of she has been received low dose of this drug.

Strongyloides venezuelensis experimental infection in rats was treated by two different oral preparations of ivermectin, 0.2 mg/kg. One was a human formula used by WHO in the treatment of onchocerciasis; the other was a veterinary preparation. Adult worms and larvae were evaluated. The human formulation cleared both forms in 59.3% (adult worms) and 73.0% (larvae), whereas the veterinary one cleared 98.0% and 84.2%, respectively. The antilarval action is very useful when treating systemic strongyloidiasis.

Cyclosporin A has activity "in vitro" against trypomastigotes of Trypanosoma cruzi. We tried to evaluate, in an "in vitro" model, using variable concentrations in whole blood contaminated with known numbers of parasites and injecting this blood after a two hour incubation period in mice if it was possible to prevent infection. In this model the drug, in the concentrations used, was unable to prevent infection.

Classical serological screening assays for Chagas' disease are time consuming and subjective. The objective of the present work is to evaluate the enzyme immuno-assay (ELISA) methodology and to propose an algorithm for blood banks to be applied to Chagas' disease. Seven thousand, nine hundred and ninety nine blood donor samples were screened by both reverse passive hemagglutination (RPHA) and indirect immunofluorescence assay (IFA). Samples reactive on RPHA and/or IFA were submitted to supplementary RPHA, IFA and complement fixation (CFA) tests. This strategy allowed us to create a panel of 60 samples to evaluate the ELISA methodology from 3 different manufacturers. The sensitivity of the screening by IFA and the 3 different ELISA's was 100%. The specificity was better on ELISA methodology. For Chagas disease, ELISA seems to be the best test for blood donor screening, because it showed high sensitivity and specificity, it is not subjective and can be automated. Therefore, it was possible to propose an algorithm to screen samples and confirm donor results at the blood bank.Os testes sorológicos clássicos utilizados na triagem de doadores de sangue são trabalhosos e subjetivos. O objetivo do presente trabalho é o de avaliar a metodologia imuno-enzimática (ELISA) e propor um algorítmo para doença de Chagas em bancos de sangue. Foram estudados 7999 doadores de sangue e/ou componentes cujas amostras foram testadas com o objetivo de tria-las sorologicamente para doença de Chagas utilizando hemaglutinação passiva reversa (RPHA) e imunofluorescência indireta (IFA). As amostras reativas em pelo menos uma destas metodologias, foram retestadas com reativos diferentes por RPHA, IFA e fixação de complemento (CFA). Esta estratégia nos permitiu criar um painel de 60 amostras com as quais tornou-se possível a avaliação do método imunoenzimático (ELISA). A sensibilidade da triagem dos doadores pelos métodos ELISA e IFA foi de 100%. A especificidade foi melhor para a metodologia imunoenzimática. O teste ELISA parece ser o ideal para triagem em bancos de sangue pois é altamente sensível, específico, não é subjetivo e pode ser automatizado. Desta forma, torna-se possível a formulação de um algorítimo a ser utilizado na triagem sorológica e confirmação de resultados em doadores de bancos de sangue.

Quinine was the first antimalarial drug to be employed and also the first resistance was noticed to. After 1960 quinine urged to be reintroduced in routine therapy alone or in combination. Aiming at evaluating the effectiveness of different schedules we studied 484 patients seen at the Malaria Laboratory. We used quinine alone in 126 patients, quinine plus sulfadoxine and pyrimethamine in 119 patients and quinine plus tetracycline in 239 patients. The results shown that 81% of all patients were treated with success and only 0.6% were R2. and there is no R3. We emphasize a high resistance rate to quinine either alone (23.1%) or associated to sulfadoxine and pyrimethamine (37.8%). A higher resistance rate seen with the combination might be linked to the smaller dose of quinine used in that instance. It is worth noting the high cure rate with the quinine-tetracycline association.

Quality of life was evaluated in 11 patients with Chagas' disease 26 to 126 months after submission to heart transplantation. There was an objective improvement in their quality of life, after the transplant.

Patients with chronic Chagas' disease and simultaneous medical problems treated with corticosteroid were studied in order to evaluate steroid influence on chronic Trypanosoma cruzi infection. Parasitological assessment, radiological and electrocardiographic studies as well as non specific tests were performed in patients and in a control group that included chronic infected patients not treated with steroid. Xenodiagnosis showed a clear increase in T. cruzi parasitemia, related to the corticosteroid dosage, without clinical manifestations during the study follow-up period.

The diagnosis of intestinal infection by Cryptosporidium sp is crucial today; with the progression of the AIDS epidemic, many cases of cryptosporidiosis have appeared in this setting and in other immunodeficiency diseases. We compared the advantages and disadvantages of Heine's method and modified Kinyoun's method in the following parameters: morphology of the parasite, quantitation of cysts, stability of the staining characteristics timewise on the slides and time spend at staining. All positive fecal smears were obtained from patients with AIDS. The sensitivity of these two techniques was the same. The choice should be made by the best aspects of each method. Heine's was better for quantitation of the cysts and was faster. Kinyoun's was better for conserving the stained smear.

Influence of Montenegro skin test for American tegumentar leishmaniasis was evaluated to verify possible interference in serological diagnosis for this disease, performed by immunoenzymatic assay (ELISA). If this interference could occur, it would hamper scientific, epidemiological and patient care; happily we did not find any interference on serological diagnosis by performance of skin testing.

Ten patients with mucosal lesions caused by American tegumental leishmaniasis were treated with pentamidine isethionate at the dose 4 mg/kg on alternate days by the intravenous route. The mean posology was 2,140 mg. Healing of the lesions occurred in 9 (90%) of the patients who completed treatment. There was no recurrence during a follow-up time of 1 to 24 months (mean, 7,7 months). One patient discontinued treatment before healing of the lesion because be developed diabetes mellitus. In 3 (30%) patients, blood exams showed increased urea and creatinine levels and leucopenia, which were corrected by increasing the interval between administrations of the drug. Pentamidine isethionate is efficient in bringing about cicatrization of the lesions but needs further evaluation in terms of its value in preventing recurrence.

In spite of the efforts to control the spread of tuberculosis worldwide this disease remains one of the biggest problems in public health. Multiresistance has a dramatic effect in this scenario. Non compliance with treatment is directly related to disease spread and the appearance of multiresistance bacilli. Aiming to verify if it is possible to identify patients prone to non compliance from data obtained in the first visit we have studied a population enrolled in a prospective study. Among 257 consecutive patients evaluated between january 1991 and january 1994, we compared 87 patients that abandoned treatment before six months (group A) with 97 that completed six months of treatment (group C). The abandon rate in this group as 33.85% which is larger than 12.9% rate reported by the Health Ministry. Comparing A to C, only the prevalence of alcoholism (A 33.3% x C 22.5%, p = 0.015) and risk behavior for HIV infection (A 27.6% x C 10.2%, p = 0.046), as well as the frequency of non pulmonary disease (A 38.0% x C 24.5%, p = 0.034) were significantly different between both groups. Regarding the moment of abandon (0, 1st or 3rd month) there was no difference in the A group. We conclude that patients at high risk of abandoning tuberculosis treatment can be identified with data obtained at the first visit, allowing to establish a different policy such as supervised treatment for this population.

The diagnosis of ocular toxoplasmosis is based primarily on clinical presentation and laboratory tests described else where. Eventually, unusual clinical presentation, as well unusual pathologic findings occur, mainly in immunosuppressed individuals. The authors report a case of a female patient from Paraná with a progressive ocular disease, for at least three years, without definite diagnosis. After an exhaustive clinical and laboratory investigation, as well empiric medical treatment, without success, it was decided to enucleate the atrofic organ and to proceed to a histologic examination. It revealed a cronic and inspecific inflammatory process without any specific agent. However the immunohistochemical technique was able to detect Toxoplasma gondii antigens in the ocular tissue. This technique provides an alternative method for the diagnosis of unusual forms of toxoplasmosis.

The authors treated with paromomycin 25 patients, with AIDS and cryptosporidiosis. The drug was given orally in a doses of 500 mg qid, for a period of 14 days. Tolerance was good, with just two cases of mild side-effects. Clinical improvement was obtained in 19 (76%) patients. Parasitological cure, however, occurred only in a low percentage (25%). In some cases where initial success was observed, recrudescence occurred after some weeks or few months, but with retreatment again clinical improvement was obtained. Even if it does not lead to frequent parasite eradication, the good clinical results and tolerance permit us to consider paromomycin one of the few drugs effective for the treatment of cryptosporidial diarrhea in AIDS patients. Studies with maintainance therapy are indicated.

To analyse prevalence, clinical features and organ involvement in viral infections occuring after heart transplantation.One hundred consecutive heart transplantation patients were studied. The follow-up was three to 90 (mean 23.32 +/- 25.97) months. Viral infections were diagnosed using the Center for Disease Control criteria.Viral infections were responsible for 51 infections, 19.6% of all infections in this patient population. Herpesvirus infection was the most common etiology: 32 (59.25%) of all viral infections were caused by reactivation of or reinfection by cytomegalovirus. Of those infections 27 (84.37%) occurred in the first three weeks following surgery. Only 4 (12.50%) of those showed clinical signs of cytomegalovirus disease. Other herpesvirus causing infections were herpes simplex and varicella-zoster virus.Infections are common after heart transplantation and viral infections of herpesviridae family are important causes of those infections; usually as reactivation in an immune suppressed patient. The most important viral infections were caused by reactivation of or reinfection by cytomegalovirus.

To evaluate prevalence, causes, clinical aspects, topography and deaths due to fungal infections diagnosed in a series of patients submitted to heart transplantation.100 consecutive patients submitted to heart transplantation were studied. Follow-up was three to 90 (mean 25.38 +/- 25.97) months. Fungal infections were diagnosed by the Centers for Disease Control criteria.Forty seven fungal infections were found, with three deaths caused mainly by fungal infection. The most common infection in this series was oral infection by Candida albicans, Acremonium sp, Aspergillus sp, Candida tropicalis, Histoplasma capsulatum and Pneumocystis carinii were also responsible for infections in this patient population.Fungal infections caused three deaths in this series, and were responsible for increased morbidity. The authors suggest prophylactic and therapeutic recommendations.