Leishmaniose visceral em crianças no estado de Mato Grosso do Sul, Brasil : contribuição ao diagnóstico e ao tratamento

Tese (doutorado)—Universidade de Brasília, Faculdade de Medicina, 2006.A faixa etária pediátrica é especialmente atingida pela leishmaniose visceral (LV), uma doença atualmente em franca expansão no Mato Grosso do Sul e em outras localidades brasileiras. O diagnóstico e o tratamento da LV em crianças foram estudados retrospectivamente, através da análise dos dados de pacientes internados no Hospital Universitário da Universidade Federal de Mato Grosso do Sul, no período de janeiro de 1998 a fevereiro de 2005, o que resultou em cinco estudos. No primeiro estudo, identificou-se a forma de apresentação da patologia nas crianças do Estado. A LV vem se apresentando como uma doença de evolução rápida nessa região, evidenciando um padrão diferente do considerado típico para a patologia, habitualmente prolongada e de longa duração. O diagnóstico de pacientes em fase evolutiva não muito adiantada e o tratamento adequado dos casos resultaram em uma doença de baixa mortalidade (2,6%). Os métodos convencionalmente utilizados no diagnóstico da LV foram analisados. A combinação de dois testes tradicionais, como a microscopia direta do aspirado medular e a sorologia por Imunofluorescência, possibilitou a confirmação do diagnóstico na quase totalidade dos casos em que esses exames foram realizados (98,5%). Enfatiza-se a necessidade da obtenção da sorologia, frequentemente colocada em segundo plano, devido à preferência dos profissionais locais pela realização do mielograma como única forma de diagnóstico. Pela primeira vez no Estado, utilizou-se um método de biologia molecular no estudo de casos de LV. A utilização da PCR (reação em cadeia da polimerase) na detecção de DNA de Leishmania em lâminas de aspirado medular, coradas por Giemsa e estocadas, foi avaliada. O teste foi altamente sensível (92,3%) e específico (97,7%), mostrando-se útil na elucidação de casos difíceis. Os aspectos mais importantes relacionados ao tratamento da doença foram avaliados, descrevendo-se as drogas utilizadas, seus efeitos adversos, a resposta terapêutica, o tempo de tratamento e as dificuldades no manejo do mesmo. O antimoniato de meglumina mostrou-se eficaz e seguro na infância e, apesar da existência atual de novas opções para tratamento, sua indicação como primeira escolha terapêutica em crianças é ainda a mais adequada em nosso meio. O problema da recidiva após o tratamento também foi enfocado; são descritos 4 casos em crianças, com discussão de aspectos recentes sobre o assunto. _______________________________________________________________________________ ABSTRACTThe pediatric age range is particularly affected by visceral leishmaniasis, a disease that is currently spreading steadily in the state of Mato Grosso do Sul and in other areas in Brazil. The diagnosis and treatment of the disease in childhood were investigated retrospectively by analyzing data of patients admitted to the Teaching Hospital of Universidade Federal de Mato Grosso do Sul from January 1998 to February 2005. The investigation was composed of five studies. The clinical presentation of the pathology in children in Mato Grosso do Sul was identified. Visceral leishmaniasis has been exhibiting fast evolution in the region, with a mode of presentation that differs from the pattern viewed as typical for the pathology, usually of long-lasting course. Diagnosis of patients in a not much advanced phase of the disease and the availability of suitable treatment have resulted in an illness of low mortality. The methods conventionally employed in the diagnosis of visceral leishmaniasis were analyzed. The combination of two traditional tests—direct microscopy of bone marrow aspirates (BMAs) and immunofluorescence serology—allowed diagnosis to be reached in nearly all the cases for which these tests were performed (98.5%). Emphasis is placed on the need for conducting serological testing, a procedure often assigned secondary importance, as local health professionals tend to favor the use of myelograms as the only diagnostic method. For the first time in Mato Grosso do Sul a molecular biology method has been applied to the study of cases of visceral leishmaniasis. The use of polymerase chain reaction (PCR) for detection of Leishmania DNA in archived Giemsa-stained BMA slides was evaluated. The technique was found to be useful in the diagnostic clarification of difficult cases, given its high sensitivity (92.3%) and specificity (97.7%). The most important aspects related to treatment of the disease were evaluated, along with a description of the drugs prescribed and their adverse effects, therapeutic response, length of treatment, and difficulties posed for the management of treatment. Meglumine antimoniate was found to be effective and safe in pediatric patients and, despite the current availability of new treatment options, its indication as first-line therapy in the treatment of childhood visceral leishmaniasis is still the most suitable in our setting. The issue of post-treatment relapse was also addressed in one the study; four cases of relapse in children are described, with a discussion on recently addressed aspects

Sensitivity and specificity of polymerase chain reaction in Giemsastained slides for diagnosis of visceral leishmaniasis in children

The aim of this study was to evaluate the sensitivity and specificity of polymerase chain reaction (PCR) in the detection of Leishmania DNA in archived Giemsa-stained bone marrow slides for diagnosis of visceral leishmaniasis (VL), and to compare PCR with conventional diagnostic techniques, like direct microscopy and parasite culture. Specimens of archived Giemsa-stained bone marrow slides from 91 patients with VL and from 79 controls with other diseases or conditions were studied. PCR showed the highest sensitivity (92.3%) and had good specificity (97.5%). Direct examination detected 79.1% and culture 59% of positive samples. In addition, PCR was able to detect VL in 16 of 19 patients (84.2%) with negative microscopy. PCR in Giemsa-stained bone marrow slides is a suitable tool for confirming diagnosis in patients with VL and may be useful in the diagnosis of difficult cases. Slide smears are easily stored, do not require special storage conditions such as low temperatures, and can be easily mailed to centers where PCR is available, making it an excellent option for diagnosis in the field

Pertussis in the central-west region of Brazil: one decade study

In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months

Polymerase chain reaction of peripheral blood as a tool for the diagnosis of visceral leishmaniasis in children

The diagnosis of visceral leishmaniasis (VL) generally requires the use of invasive tests for the collection of infected tissue (aspirates of bone marrow, spleen, liver or lymph nodes). This difficulty has led to the search for safer and less painful techniques to confirm the occurrence of the disease in children. Polymerase chain reaction (PCR) is a method that is advantageous in that it allows the use of peripheral blood samples for diagnosis. This paper reports the utilisation of PCR on peripheral blood samples to diagnose VL in 45 children in Mato Grosso do Sul, Brazil. This technique is compared with methods carried out using tissue collected by invasive procedures, including direct microscopy, culture and detection of Leishmania DNA by PCR in bone marrow aspirates. The results show that PCR of peripheral blood provides great sensitivity (95.6%) that is similar to that from the PCR of bone marrow aspirates (91.1%) and higher than that achieved with microscopy (80%) or culture (26.7%) methods. PCR of peripheral blood proved to be a suitable tool for the diagnosis of VL in children because it is highly sensitive and safe, with tissue collection being less invasive than in traditional tests