Evaluation of the double diffusion, enzyme immunoassay and immunoblotting techniques, for the diagnosis of human hydatid disease in tropical areas

Hydatid disease in tropical areas poses a serious diagnostic problem due to the high frequence of cross-reactivity with other endemic helminthic infections. The enzyme-linked-immunosorbent assay (ELISA) and the double diffusion arc 5 showed respectively a sensitivity of 73% and 57% and a specificity of 84-95% and 100%. However, the specificity of ELISA was greatly increased by using ovine serum and phosphorylcholine in the diluent buffer. The hydatic antigen obtained from ovine cyst fluid showed three main protein bands of 64,58 and 30 KDa using SDS PAGE and immunoblotting. Sera from patients with onchocerciasis, cysticercosis, toxocariasis and Strongyloides infection cross-reacted with the 64 and 58 KDa bands by immunoblotting. However, none of the analyzed sera recognized the 30 KDa band, that seems to be specific in this assay. The immunoblotting showed a sensitivity of 80% and a specificity of 100% when used to recognize the 30 KDa band.

VISCERAL LARVA MIGRANS AND TROPICAL PYOMYOSITIS: A CASE REPORT

We report a case of tropical pyomyositis in a boy who presented with a severe febrile illness associated with diffuse erythema, and swelling in many areas of the body which revealed on operation extensive necrotic areas of various muscles that required repeated débridement. The patient gave a history of contact with dogs, and an ELISA test for Toxocara canis was positive. He also presented eosinophilia and high serum IgE levels. Staphylococcus aureus was the sole bacteria isolated from the muscles affected. We suggest that tropical pyomyositis may be caused by the presence of migrating larvae of this or other parasites in the muscles. The immunologic and structural alterations caused by the larvae, in the presence of concomitant bacteremia, would favour seeding of the bacteria and the development of pyomyositis.

Infecções por Tinea capitis em meios desfavorecidos da periferia de Lisboa - Estudo em crianças do Bairro de Santa Filomena, Concelho da Amadora

PLAVRAS – CHAVE: Tinea capitis, colheita de amostras, diagnóstico laboratorial, questionário, estratégias de intervenção Os fungos dermatófitos estão entre os mais disseminados e prevalentes das doenças causadas por fungos, afectam milhões de pessoas em todas as partes do mundo. A tinea capitis é a infecção fúngica mais comum na idade pediátrica, é contagiosa, havendo aumento do risco de infecção quando existe partilha de objectos e poucos cuidados de higiene. É uma infecção que afecta essencialmente crianças e pré-adolescentes, sendo que estes apresentam mais susceptibilidade e exposição à infecção. É uma infecção com distribuição mundial, sendo muito comum em África. Anteriormente as áreas endémicas estavam mais definidas, mas com o aumento das viagens inter-continentais e da imigração novas doenças têm-se expandido nos países de acolhimento, daí o aumento da prevalência desta infecção nos países Europeus. Para além de ser uma doença com um impacto social marcado, levando as crianças à restrição de actividades sociais, como a ida à escola e todas as consequências que daí advêm, como por exemplo a exclusão. Perante esta situação, realizou-se um estudo de forma a identificar a prevalência da tinea capitis em crianças com idades entre os 1-14 anos no Bairro de Santa Filomena, Concelho da Amadora, Portugal, e os conhecimentos (definição, diagnóstico e tratamento) dos encarregados de educação/responsáveis pela criança sobre a doença, para se poderem traçar estratégias de intervenção. A população era composta por 127 crianças, que frequentavam a Associação da Encosta Nascente e o Centro de Catequese leccionado no Bairro de Santa Filomena, sendo 44,9% do Sexo Masculino e 55,1% do sexo Feminino, com idades pré-escolar e escolar. Utilizaram-se três técnicas de diagnóstico, observação clínica, microscopia e exame cultural. As amostras do couro cabeludo das crianças foram analisadas no Laboratório de Micologia do Instituto de Higiene e Medicina Tropical. A prevalência de crianças com doença activa foi de 17,3% e de portadoras 19,7%. Foram identificados dois agentes etiológicas, Microsporum audouinii e o Tricophyton soudanense (fungos de origem Africana). Aos encarregados de educação/responsáveis pelas crianças aplicou-se um questionário sobre aspectos relacionados com a infecção por tinea capitis. Os respondentes mostraram poucos conhecimentos, alguns até incorrectos. Tendo em vista o controlo da infecção, é necessário envolver vários parceiros, como os Centros de Saúde e Centros de Educação (Creches /Escolas/Catequese), para além dos encarregados de educação, intervindo na sua formação com Sessões de Educação, rastreios, diagnóstico e tratamento, medidas preventivas e melhorias das condições de higiene pessoal e ambiental.

Clinical and epidemiological aspects of HTLV-II infection in São Paulo, Brazil: presence of Tropical Spastic Paraparesis/HTLV-Associated Myelopathy (TSP/HAM) simile diagnosis in HIV-1-co-infected subjects

In this study, the epidemiological and clinical features observed in solely HTLV-II-infected individuals were compared to those in patients co-infected with HIV-1. A total of 380 subjects attended at the HTLV Out-Patient Clinic in the Institute of Infectious Diseases "Emilio Ribas" (IIER), São Paulo, Brazil, were evaluated every 3-6 months for the last seven years by infectious disease specialists and neurologists. Using a testing algorithm that employs the enzyme immuno assay, Western Blot and polymerase chain reaction, it was found that 201 (53%) were HTLV-I positive and 50 (13%) were infected with HTLV-II. Thirty-seven (74%) of the HTLV-II reactors were co-infected with HIV-1. Of the 13 (26%) solely HTLV-II-infected subjects, urinary tract infection was diagnosed in three (23%), one case of skin vasculitis (8%) and two cases of lumbar pain and erectile dysfunction (15%), but none myelopathy case was observed. Among 37 co-infected with HIV-1, four cases (10%) presented with tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM) simile. Two patients showed paraparesis as the initial symptom, two cases first presented with vesical and erectile disturbances, peripheral neuropathies were observed in other five patients (13%), and seven (19%) patients showed some neurological signal or symptoms, most of them with lumbar pain (five cases). The results obtained suggest that neurological manifestations may be more frequent in HTLV-II/HIV-1-infected subjects than those infected with HTLV-II only.

T CD4+ cells count among patients co-infected with human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus type 1 (HTLV-1): high prevalence of tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM)

INTRODUCTION: HIV positive patients co-infected with HTLV-1 may have an increase in their T CD4+ cell counts, thus rendering this parameter useless as an AIDS-defining event. OBJECTIVE: To study the effects induced by the co-infection of HIV-1 and HTLV-1 upon CD4+ cells. MATERIAL AND METHODS: Since 1997, our group has been following a cohort of HTLV-1-infected patients, in order to study the interaction of HTLV-1 with HIV and/or with hepatitis C virus (HCV), as well as HTLV-1-only infected asymptomatic carriers and those with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM). One hundred and fifty HTLV-1-infected subjects have been referred to our clinic at the Institute of Infectious Diseases "Emílio Ribas", São Paulo. Twenty-seven of them were also infected with HIV-1 and HTLV-1-infection using two ELISAs and confirmed and typed by Western Blot (WB) or polymerase chain reaction (PCR). All subjects were evaluated by two neurologists, blinded to the patient's HTLV status, and the TSP/HAM diagnostic was based on the World Health Organization (WHO) classification. AIDS-defining events were in accordance with the Centers for Disease Control (CDC) classification of 1988. The first T CD4+ cells count available before starting anti-retroviral therapy are shown compared to the HIV-1-infected subjects at the moment of AIDS defining event. RESULTS: A total of 27 HIV-1/HTLV-1 co-infected subjects were identified in this cohort; 15 already had AIDS and 12 remained free of AIDS. The median of T CD4+ cell counts was 189 (98-688) cells/mm³ and 89 (53-196) cells/mm³ for co-infected subjects who had an AIDS-defining event, and HIV-only infected individuals, respectively (p = 0.036). Eight of 27 co-infected subjects (30%) were diagnosed as having a TSP/HAM simile diagnosis, and three of them had opportunistic infections but high T CD4+ cell counts at the time of their AIDS- defining event. DISCUSSION: Our results indicate that higher T CD4+ cells count among HIV-1/HTLV-1-coinfected subjects was found in 12% of the patients who presented an AIDS-defining event. These subjects also showed a TSP/HAM simile picture when it was the first manifestation of disease; this incidence is 20 times higher than that for HTLV-1-only infected subjects in endemic areas.

Neglected tropical diseases in Brazil

Poverty is intrinsically related to the incidence of Neglected Tropical Diseases (NTDs). The main countries that have the lowest human development indices (HDI) and the highest burdens of NTDs are located in tropical and subtropical regions of the world. Among these countries is Brazil, which is ranked 70th in HDI. Nine out of the ten NTDs established by the World Health Organization (WHO) are present in Brazil. Leishmaniasis, tuberculosis, dengue fever and leprosy are present over almost the entire Brazilian territory. More than 90% of malaria cases occur in the Northern region of the country, and lymphatic filariasis and onchocerciasis occur in outbreaks in a particular region. The North and Northeast regions of Brazil have the lowest HDIs and the highest rates of NTDs. These diseases are considered neglected because there is not important investment in projects for the development of new drugs and vaccines and existing programs to control these diseases are not sufficient. Another problem related to NTDs is co-infection with HIV, which favors the occurrence of severe clinical manifestations and therapeutic failure. In this article, we describe the status of the main NTDs currently occurring in Brazil and relate them to the HDI and poverty.

Epidemiology of neglected tropical diseases in transplant recipients: review of the literature and experience of a Brazilian HSCT center

The rising success rate of solid organ (SOT) and haematopoietic stem cell transplantation (HSCT) and modern immunosuppression make transplants the first therapeutic option for many diseases affecting a considerable number of people worldwide. Consequently, developing countries have also grown their transplant programs and have started to face the impact of neglected tropical diseases (NTDs) in transplant recipients. We reviewed the literature data on the epidemiology of NTDs with greatest disease burden, which have affected transplant recipients in developing countries or may represent a threat to transplant recipients living in other regions. Tuberculosis, Leprosy, Chagas disease, Malaria, Leishmaniasis, Dengue, Yellow fever and Measles are the topics included in this review. In addition, we retrospectively revised the experience concerning the management of NTDs at the HSCT program of Amaral Carvalho Foundation, a public transplant program of the state of São Paulo, Brazil.