Laboratory diagnosis of amebiasis in a sample of students from southeastern Brazil and a comparison of microscopy with enzyme-linked immunosorbent assay for screening of infections with Entamoeba sp.

Introduction: Epidemiological studies on amebiasis have been reassessed since Entamoeba histolytica and E. dispar were first recognized as distinct species. Because the morphological similarity of these species renders microscopic diagnosis unreliable, additional tools are required to discriminate between Entamoeba species. The objectives of our study were to compare microscopy with ELISA kit (IVD®) results, to diagnose E. histolytica infection, and to determine the prevalence of amebiasis in a sample of students from southeastern Brazil. Methods: In this study, diagnosis was based on microscopy due to its capacity for revealing potential cysts/trophozoites and on two commercial kits for antigen detection in stool samples. Results: For 1,403 samples collected from students aged 6 to 14 years who were living in Divinópolis, Minas Gerais, Brazil, microscopy underestimated the number of individuals infected with E. histolytica/E. dispar (5.7% prevalence) compared with the ELISA kit (IVD®)-based diagnoses (15.7% for E. histolytica/E. dispar). A comparison of the ELISA (IVD®) and light microscopy results returned a 20% sensitivity, 97% specificity, low positive predictive value, and high negative predictive value for microscopy. An ELISA kit (TechLab®) that was specific for E. histolytica detected a 3.1% (43/1403) prevalence for E. histolytica infection. Conclusions: The ELISA kit (IVD®) can be used as an alternative screening tool. The high prevalence of E. histolytica infection detected in this study warrants the implementation of actions directed toward health promotion and preventive measures. .

Parasitoses oportunistas em pacientes com o vírus da imunodeficiência humana / Opportunistic parasitosis in patients with the virus of the human immunodeficiency

As parasitoses representam um dos maiores problemas de saúde pública do Brasil. Mesmo com todo desenvolvimento tanto na área farmacológica quanto nas medidas de saneamento básico e educação sanitária, as doenças causadas por esses endoparasitas são uma das mais frequentes em todo o território nacional. Para os pacientes portadores do vírus da imunodeficiência humana (HIV), o risco de infecção parasitária é consideravelmente mais elevado, visto que tais indivíduos apresentam diminuição significativa na contagem de células T-CD4+. Essa imunodepressão proporciona não só maior suscetibilidade à contaminação por agentes oportunistas,mas também sintomatologia mais grave. Sendo assim, a infecção parasitária contribui para o declínio abrupto da condição clínica do paciente com síndrome da imunodeficiência adquirida (SIDA). O objetivo desse estudo foi enfatizar a necessidade de se combatera proliferação das parasitoses oportunistas, principalmente nos pacientes portadores do HIV. Realizou-se levantamento bibliográfico em livros didáticos e em base de dados Medline, Scielo e LILACS. Cinquenta e oito publicações foram selecionadas com o intuito de elucidar a fisiopatologia das principais e mais comuns parasitoses intestinais em associação com o vírus HIV-1 ou HIV-2. O tratamento das doenças parasitárias e o acompanhamento do estadiamento clínico e imunológico buscam proporcionar ao paciente melhor qualidade de vida e, sobretudo, evitar possíveis intercorrências médicas, as quais podem resultar na elevação das taxas de morbimortalidade. O sucesso dessa conduta pode ser alcançado caso ocorra o diagnóstico precoce das infecções parasitárias. Para isso, é indispensável que o paciente realize não só exames parasitológicos regulares, mas que também receba a terapia farmacológica correta e o acompanhamento frequente da sua evolução clinica e imunológica. As diretrizes e recomendações do Ministério da Saúde enfatizam a necessidade de se diagnosticar e tratar todos os indivíduos com SIDA infectados por agentes parasitários oportunistas.

Parasitosis represent one of the greatest Brazilian public health problems. Even with all the development in pharmacology, basic sanitation and sanitary education areas, the diseases caused by these endoparasites constitute the most frequent diseases in the entire national territory. For the patients who are carriers of the human immunodeficiency virus (HIV), the risk of parasitic infection is considerably more elevated, since such subjects show significant fall in CD4+ T cells count. This immunodepression not only causes higher susceptibility to contamination by opportunistic agents, but also more severe symptomatology. Thus, parasitic infection contributes for the abrupt decline of the clinical condition of the patient with acquired immunodeficiency syndrome (AIDS). The purpose of the present study was to emphasize the need to fight against the proliferation of opportunistic parasitosis, especially in HIV-infected patients. A bibliographic survey was conducted in didactic books and in the databases Medline, Scielo and LILACS. Fifty-eight publications were selected with the purpose to clarify the pathophysiology of the most common and most important intestinal parasitosis in association with the HIV-1 or HIV-2 virus. The treatment of parasitic diseases and the follow-up of clinical and immunological staging aim at providing the patient with a bette rquality of life and, above all, avoiding possible medical intercurrences, which can result in the elevation of the morbid-mortality rates. The success of this intervention can be reached if the early diagnosis of parasitic infection occurs. Therefore, it is essential that the patient not only undergoes regular parasitic examinations, but also receives correct drug therapy and frequent follow-up of his/her clinic and immunological evolution. The guidelines and recommendations of the Health Ministry emphasize the necessity to diagnose and treat all the individuals with acquired immunodeficiency syndrome infected with opportunistic parasitic agents.