Immunohistochemistry and polymerase chain reaction on paraffin-embedded material improve the diagnosis of cutaneous leishmaniasis in the Amazon region.

BACKGROUND: Recently, there has been an increase in the incidence of cutaneous leishmaniasis (CL), which represents an important health problem. This increase may be related to the epidemiologic expansion of the infective agent and the increase in tourism in tropical areas. The difficulty in clinical diagnosis, mainly in areas in which CL is not the first consideration of local physicians, has intensified efforts to describe diagnostic tests, which should be specific, sensitive, and practical. Amongst the new tests described are those including nucleic acid amplification (polymerase chain reaction, PCR) and immunohistochemistry (IHC). METHODS: In this study, we evaluated the sensitivity of a PCR based on small subunit (SSU) ribosomal DNA, in comparison with IHC using Leishmania spp. antibodies, in biopsies embedded in paraffin. RESULT: The results indicated a total sensitivity of 96% (90.9% with PCR and 68.8% with IHC), showing the possibility of using paraffin-embedded biopsies to diagnose CL. CONCLUSION: We propose the use of the two tests together as a routine protocol for diagnosis. This would require the provision of local medical services to perform molecular biology techniques and adequate Leishmania antibodies.

[Intestinal parasitosis in Indians of the Mapuera community (Oriximiná, State of Pará, Brazil): high prevalence of Blastocystis hominis and finding of Cryptosporidium sp and Cyclospora cayetanensis]. / Parasitoses intestinais de indígenas da comunidade Mapuera (Oriximiná, Estado do Pará, Brasil): elevada prevalência de Blastocystis hominis e encontro de Cryptosporidium sp e Cyclospora cayetanensis.

Occurrences of intestinal parasitosis in Indians of the Mapuera community (Oriximiná, State of Pará, Brazil) were evaluated. Within the context of group assessment, this study makes a contribution towards adequate knowledge of this subject, which is significant from a medical-sanitary point of view. Parasitological examination of feces from 83 individuals, performed using four different methods, could be considered to have reasonable amplitude for establishing diagnoses. Protozoan cysts and helminth eggs of many types were found, even with significant percentages. The frequent presence of Blastocystis hominis (57.8%), along with findings of Cryptosporidium sp (3.6%) and Cyclospora cayetanensis (10.8%), deserved highlighting with specific comments. The findings show that these Indians live in an environment in which poor hygiene conditions prevail. In particular, these facilitate the dissemination of protozoa and helminths through contact with the soil or through intake of contaminated water and food.

Local immunological factors associated with recurrence of mucosal leishmaniasis.

Recurrence of mucosal leishmaniasis (ML) is frequent, but the causative mechanisms are unknown. Our aim was to compare cellular and cytokine patterns of lesions from ML that evolved to recurrence or cure in order to determine the risk factor associated with recurrence. Lesions were evaluated by immunohistochemistry before and after therapy, and patients were followed-up for five years. Higher levels of CD4(+) T and IFN-gamma-producing cells were detected in active lesions and decreased after therapy. Macrophages and IL-10 were markedly increased in cured patients. Conversely, CD8(+) T and NK cells were higher in relapsed than in cured cases. Notably, a decrease in these cells in addition to decreased IL-10 and IFN-gamma was also observed after therapy. These data suggest that exacerbated CD8(+) activity, in addition to a poor regulatory response, could underlie an unfavorable fate with regard to ML. These markers may be useful for predicting the prognosis of ML in lesion studies.

Leishmania: origin, evolution and future since the Precambrian.

This brief review discusses the history of leishmaniasis, considering its origin from the Paleoartic, Neoartic or Neotropic. We reassess some of the theories of the likely origin of this protozoan since the beginning of life on Earth, passing through the Mesozoic and continuing to the appearance of humans. The relationship between this parasite or its ancestors, possible vectors and hosts with regard to ecological modifications is discussed. Recent molecular techniques have helped to elucidate some of the evolutionary questions regarding Leishmania, but have also brought doubts about the origin and evolution of this human parasite. PCR has been used for studies in the new discipline of paleoparasitology, helping to elucidate some of the remaining evolutionary questions. Understanding of this global condition is fundamental in determining the best approach to use against the parasite, specifically for the development of an efficient vaccine.

Mucosal leishmaniasis . Current scenario and prospects for treatment.

Leishmaniasis causes significant morbidity and mortality and thus constitutes a serious public health problem. Even though it has long been endemic in developing countries, in recent years the economic globalization and the increased volume of international travel have extended its prevalence in developed countries. In addition, native populations may be exposed to the infection through blood transfusion and the use of blood products produced from infected asymptomatic individuals. Mucosal leishmaniasis (ML) is a chronic form of this infection, which attacks the mucosa. In most cases this form of leishmaniasis results from the metastatic spread of Leishmania (Viannia) braziliensis from cutaneous lesions. It is a healthcare issue because of its wide demographic distribution, its association with significant morbidity levels, and because of the pressing concern that tourists who travel to endemic areas might present the disease even years later. The treatment currently available for ML is based on drugs such as pentavalent antimony-containing compounds, amphotericin B deoxycholate and pentamidine and often guarantees a satisfactory clinical response. Nevertheless, it also frequently provokes serious side effects. This review offers a critical analysis of the drugs now available for the treatment of ML as also of the future prospects for the treatment of the disease.

Treatment of mucosal leishmaniasis in Latin America: systematic review.

Mucosal leishmaniasis (ML) is an important endemic disease and public-health problem in underdeveloped countries because of its significant morbidity and mortality. Increases in ecological tourism have extended this problem to developed countries. This form of leishmaniasis, caused by reactivation after primary cutaneous lesion, has a natural history of progressive destruction of the nasal septa and soft and hard palates, causing facial disfiguration and leading to respiratory disturbances. Treatment of ML, based on several therapies, depends on use of toxic compounds, and few drugs have emerged over the past 40 years. Drug resistance has increased, and the cure rate is no better than 70% in the largest studies. Despite these data, there has been no systematic review of therapies used to treat this important tropical disease. The aim of this study is to determine the best drug management for treatment of ML in Latin America based on the best studies offered by the medical literature. The MEDLINE, LILACS, EMBASE, Web of Science, and Cochrane Library databases were searched to identify articles related to ML and therapy. The studies were independently selected by 2 authors. Articles with sufficient data for cure and treatment failures, internal and external validity information, and > 4 patients in each treatment were included. Validation of this systematic review was based on guidelines to guarantee quality; 22 articles met our inclusion criteria. Stibogluconate achieved a 51% cure rate (76/150 patients), and 88% of patients treated with meglumine were cured (121 patients). Pentamidine and amphotericin were as effective as meglumine. Use of itraconazole and other therapies (pentoxifylline, allopurinol, or interferon-gamma) was controversial, and numbers of patients in some studies were insufficient for statistical analysis. Meglumine may be the drug of choice in the treatment of ML, as it offers similar cure rates when compared with amphotericin B and pentamidine. Cost, adverse effects, local experience, and availability of drugs to treat ML are strong points to be considered before determining the best management of this disease, especially in developing countries.

Successful treatment of cutaneous leishmaniasis with lipid formulations of amphotericin B in two immunocompromised patients.

Pentavalent antimonial drugs are habitually the first choice for treating leishmaniasis, although they possess well-known toxicity and may present some therapeutic failure. Lipid formulations of amphotericin B (LFAB) have been increasingly used for treating several types of leishmaniasis. However, the administration of such lipid formulations specifically to patients with cutaneous leishmaniasis (CL) is still rare, including immunocompromised patients to whom standard treatments are more frequently contraindicated. We describe here two cases of immunocompromised patients with CL, one of them with AIDS, representing the first case of AIDS and CL co-infection treated with LFAB described in the literature. The patient achieved therapeutic success with a total 1.500 mg dose of amphotericin B colloidal dispersion. The other had diabetes mellitus as well as kidney failure and was under dialysis, having obtained the healing of lesion with a total dose of 600 mg of liposomal amphotericin B. Thus, the authors suggest that LFAB can represent a safe, efficient and less toxic therapeutic alternative to pentavalent antimonials, as well as to the so-called second line drugs, pentamidine and amphotericin B deoxycholate.

Trypanosoma cruzi parasitemia in chronic Chagas disease: comparison between human immunodeficiency virus (HIV)-positive and HIV-negative patients.

This study evaluated Trypanosoma cruzi parasitemia in persons with chronic Chagas disease, compared the parasitemia in human immunodeficiency virus (HIV)-positive and -negative subjects, and, for HIV-positive subjects, analyzed the association between parasitemia and occurrence of acquired immunodeficiency syndrome-defining illnesses, CD4 cell counts, HIV loads, and antiretroviral therapy. In total, 110 adults with chronic Chagas disease (29 HIV positive, 81 HIV negative) were studied. T. cruzi parasitemia was evaluated by xenodiagnosis, blood culture, and direct microscopic examination of blood. T. cruzi parasitemia was detected significantly more frequently in HIV-positive than in HIV-negative subjects (odds ratio, 12.3; 95% confidence interval, 3.7-41.2). HIV-positive patients also had higher levels of parasitemia. No statistically significant association was seen between parasitemia and the variables of interest among the HIV-positive subjects.

Leptospiroses em equinos: inquérito sorológico / Leptospirosis in horses: serological survey

Depois de efetuar considerações sobre as três modalidades clínicas com que se apresentam as leptospiroses entre os equinos, os autores se ocupam com maiores detalhes da fluxão periódica. Relatam, a seguir, os resultados das reações de aglutinação para o diagnóstico de leptospiroses efetuadas com o soro de 118 cavalos, sem tentar estabelecer correlações com os dados clínicos que eram insuficientes. Encontraram 20 animais com soro-aglutininas anti-leptospiras (AU).

Tratamento da ascaridíase pelo hidrato de piperazina / Treatment of ascariasis by piperazine hydrate

Usando o hidrato de piperazina, trataram os autores 54 pacientes com ascaridíase. A dose diária adotada foi a de 60 mg por quilograma de peso corporal, tendo 22 indivíduos recebido a droga durante cinco dias, 28 durante sete dias e os quatro em duas séries medicamentosas de sete dias, intervaladas por igual período. Em relação a esses três esquemas de tratamento as percentagens de curas obtidas foram, respectivamente, de 63,63%, 89,28% e 100%. Salientaram os autores que, proporcionando apreciáveis índices de curas, o hidrato de piperazina pode ser considerado como recurso terapêutico dos mais eficazes, se não o principal, utilizável no tratamento da ascaridíase. Assinalaram também que tal medicação apresenta algumas vantagens que devem ser devidamente ressaltadas: não requer a adoção de cuidados especiais, praticamente não determina ao ser usada posologia efetiva manifestações tóxicas ou colaterais, pode ser facilmente administrada a crianças com pouca idade e é de baixo custo (AU).