José Luís da Silveira Baldy

Immunogenicity of three recombinant hepatitis B vaccines administered to students in three doses containing half the antigen amount routinely used for adult vaccination

We evaluated the immunogenicity of three recombinant hepatitis B vaccines, one Brazilian (Butang, Instituto Butantan) and two Korean vaccines (Euvax-B, LG Chemical Ltd. and Hepavax-Gene, Greencross Vaccine Corp.), administered intramuscularly to students aged 17 to 19 years in three 10- micro g doses (corresponding to half the amount of antigen routinely used for adult vaccination) at intervals of one month between the first and second dose, and of four months between the second and third dose. A total of 316 students non-reactive for any serological marker of hepatitis B virus infection were vaccinated: 77 (24.4%) with the Butang vaccine, 71 (22.5%) with Euvax-B, 85 (26.9%) with Hepavax-Gene and, for comparison, 83 (26.2%) with Engerix-B (GlaxoSmithKline), whose efficacy in young adults at the dose used here has been confirmed in previous studies. Similar seroconversion rates (anti-HBs > 10 mIU/mL about one month after application of the third dose) were obtained for the Butang, Euvax-B, Hepavax-Gene and Engerix-B vaccines (96.2%, 98.6%, 96.5% and 97.6%, respectively). The frequency of good responders (anti-HBs > 100 mIU/mL) was also similar among students receiving the four vaccines (85.8%, 91.6%, 89.4% and 89.2%, respectively). The geometric mean titers (GMT) of anti-HBs about one month after the third dose obtained with these vaccines were 727.78 +/- 6.46 mIU/mL, 2009.09 +/- 7.16 mIU/mL, 1729.82 +/- 8.85 mIU/mL and 2070.14 +/- 11.69 mIU/mL, respectively. The GMT of anti-HBs induced by the Euvax-B and Engerix-B vaccines were higher than those obtained with the Butang vaccine (p < 0.05); this difference was not significant when comparing the other vaccines two-by-two. No spontaneous adverse effects attributable to the application of any dose of the four vaccines were reported.

Positivity enzyme-linked immunosorbent assay (ELISA) rates for cysticercosis in the cerebro-spinal fluid (CSF) and in the patients serum with epilepsy

Fifty patients with epilepsy seen in three Londrina Neurological Services, in Parana, were studied. The positivity prevalence of the enzyme-linked immunosorbent assay (ELISA) for cysticercosis in the cerebrospinal fluid (CSF) and in the serum of these patients was 34.0% and 20.0%, respectively. There was statisticaly significant difference when these two rates were compared with the reaction positivity in the CSF and the serum in the control group, formed by individuals without neurological diseases. There was no association between the type of seisure (generalized or partial) and the positivity index of ELISA for cysticercosis in the CSF. A greater number of patients with positive ELISA for cysticercosis in the rural area dwellers was found, in relation with the urban area dwellers. From the obtained results in our study we came to the following conclusions: 1. The high positivity ELISA rates for cysticercosis in the CSF and in the patients serum with epilepsy indicate that neurocysticercosis is an important seisure cause in Londrina, PR. 2. The positivity prevalence of ELISA for cysticercosis in CSF was greater in epileptic patients from the rural area than the ones from the urban area. 3. There was no association between the type seisure (generalized or partial) and the ELISA cysticercosis positivity rate in the CSF. 4. The high positivity prevalence of ELISA in the CSF and in the epileptic patients serum in Londrina indicates the priority of performing epidemiologic inquiry to establish the real cysticercosis prevalence in the city. ELISA may be used with this finality due to its high sensibility, its low cost and its simple performance.

Prevalence of infection by Trypanosoma cruzi in 1975, in two blood banks in Londrina, Paraná, Brazil

Foi realizado inquerito sobre a positividade de reacoes sorologicas para o diagnostico de tripanossomiase americana, em 4.500 candidatos a doadores nao selecionados, atendidos em 1975, em dois bancos de sangue de Londrina, Parana, Brasil. Observou-se resultado positivo da reacao de fixacao do complemento em 299 (7,9%) dos 3.774 candidatos a doadores atendidos no Banco de Sangue do Hospital Universitario (individuos residentes predominantemente na zona rural), tendo tambem sido positivos os resultados da reacao de fixacao do complemento e do teste de imunofluorescencia indireta em 38 (5,2%) dos 726 candidatos a doadores atendidos no Instituto de Hematologia e Hemoterapia (individuos residentes predominantemente na zona urbana). Na casuistica global a positividade observada foi de 7,4%. Dentre os 337 candidatos a doadores com reacao sorologica positiva, 97 (28,7%) informaram ter doado sangue anteriormente, em outro local, 71 (21,0%) dos quais em periodo previo menor que um ano, e 42 (12,4%) em periodo previo menor que seis meses, em relacao a data do nosso exame. Comparando os dados obtidos nesta avaliacao com os de inqueritos semelhantes efetuados em 1958 em bancos de sangue deste municipio, concluiu-se que nao houve, nesse periodo, alteracao significativa nos indices de infeccao por Trypanosoma cruzi em Londrina. Chamam a atencao para a discrepância entre o reduzido numero de casos de doenca de Chagas pos-transfusional relatados na literatura e os altos indices de positividade de reacoes sorologicas para o diagnostico de tripanossomiase americana registrados em bancos de sangue de diversas regioes do Brasil. Foi ressaltada, a importância de exigir-se maior rigor e parcimonia nas indicacoes de transfusoes de sangue, e dada enfase as normas que devem ser respeitadas quando o uso desse recurso terapeutico tiver indicacao formal.

Infecção por Trypanosoma cruzi em candidatos a doador de sangue

INTRODUCAO: A transmissao transfusional da tripanossomiase americana tem-se reduzido no Brasil, com a progressiva ampliacao do controle de qualidade do sangue. Nesse sentido, realizou-se pesquisa para avaliar a atual soro-prevalencia da infeccao por Trypanosoma cruzi em candidatos a doador de sangue em Londrina, Parana (Brasil), e comparar essa taxa com a encontrada em candidatos a doador estudados em 1958 e 1975, na mesma cidade. METODO: Estudo transversal para determinacao da soroprevalencia. O imuno-diagnostico de infeccao por Trypanosoma cruzi foi realizado atraves das tecnicas imunoenzimatica (ELISA) e imunofluorescencia indireta. RESULTADOS E CONCLUSAO: A taxa de soroprevalencia encontrada foi de 1,3%. Foi detectada tendencia de queda temporal da taxa de positividade dos testes sorologicos para o diagnostico de infeccao por Trypanosoma cruzi nos bancos de sangue do municipio estudado nos anos de 1958, 1975 e 1995.INTRODUCTION: Transmission of American trypanossomiasis by transfusion has been reduced by expansion of control measures of blood quality in Brazil. A research project was, therefore, undertaken to evaluate soropositivity for Trypanosoma cruzi infection on blood donors and to compare this rate with those found in 1958 and 1975 in blood banks. METHOD: A transversal study was carried out on blood donors in Londrina, Parana, Brazil. ELISA and Immunofluorescence were the serological test techniques used in the diagnosis of Trypanosoma cruzi infection. RESULTS AND CONCLUSION: A serumprevalence rate of 1.3% was found with a tendency for positive serum findings for Trypanosoma cruzi infection on blood donors to decrease over Aime (1958, 1975, and 1995).

Intradermal vaccination of adults with three low doses (2 µg) of recombinant hepatitis B vaccine. I. Seroconversion rate and adverse effects

A total of 250 dentists (53.6% men and 46.4% women), with a mean age of 35.1 ± 9.8 years, were submitted toserological tests for the diagnosis of hepatitis B (HB) – HBsAg, anti-HBs, anti-HBc, HBeAg, and anti-HBe – using aradioimmunoassay. One or more of these markers were detected in 78 individuals (31.2%) who were excluded fromthe group to be vaccinated. Of the 172 HB-susceptible individuals, 135 (78.5%) responded to the call and wereintradermally injected with three 2 µg doses of the Belgian HB recombinant vaccine, applied at an interval of onemonth between the 1st and 2nd dose and of five months between the 2nd and 3rd dose. A new determination of HBmarkers carried out 50 days after the 3rd dose showed that 110 (81.5%) individuals had become anti-HBs positive(65.5% good responders and 34.5% poor responders). Mean serum anti-HBs titer of these 110 dentists was 42.4 US/N, similar in both sexes. The adverse effects analyzed in 106 dentists were: (a) local: pain (12.3%), burningsensation (14.1%), pruritus (25.5%), erythema (28.3%), local heat (18.9%), and a hypochromic spot (32.1%); (b)systemic (4.7%): discomfort in two patients, and fever, anorexia, and asthenia in one patient each. Intradermaladministration of a fourth 2 µg vaccine dose to 39 dentists (poor or non-responders) increased the total number ofanti-HBs-positive individuals from 110 (81.5%) to 114 (84.4%), with the number of good responders increasingfrom 72 (65.5%) to 85 (74.6%). We conclude that the Belgian recombinant vaccine applied in the scheme used hereinduces a high rate of seroconversion and causes only mild and transitory adverse effects.

Intradermal vaccination of adults with three low doses (2 µg) of recombinant hepatitis B vaccine. II. Persistence of immunity and induction of immunologic memory

Of the 110 dentists who had presented seroconversion 50 days after the intradermal application of three 2 micrograms doses of the Belgian recombinant vaccine against hepatitis B (HB), administered eight years before at an interval of one month between the 1st and 2nd doses and of five months between the 2nd and 3rd doses, 51 were included for the assessment of the persistence of immunity. None of the dentists had hepatitis or had received HB vaccine during this period. All subjects were submitted to serological tests for the detection of the following markers of hepatitis B virus (HBV) infection: HBsAg, anti-HBc, HBeAg, anti-HBe, and anti-HBs, with no HBsAg, anti-HBc, HBeAg or anti-HBe being detected. A microparticle enzyme immunoassay (MEIA) revealed the presence of anti-HBs at protective titers (> or = 10 mIU/ml) in 42 dentists (82.4%), with the anti-HBs titer being higher than 100 mIU/ml in 36 of them (70.6%) (good responders), between 10 and 100 mIU/ml in 6 (11.8%) (poor responders), and lower than 10 mIU/ml in 9 (17.6%) (non-responders). According to clinical data and serological tests, none of the dentists had presented disease or latent HBV infection during the eight years following the first vaccination. A 2 micrograms booster dose was administered intradermally to eight dentists with anti-HBs titers lower than 10 mIU/ml (non-responders) and to six dentists with titers ranging from 10 to 100 mIU/ml (poor responders); the determination of anti-HBs one month later demonstrated the occurrence of seroconversion in the eight non-responders and an increase in anti-HBs titer in the six poor responders. In summary, the present results demonstrated the prolonged persistence of protection against HBV infection and the development of immunologic memory provided by vaccination against HB--with intradermal application of three 2 micrograms doses of the Belgian recombinant vaccine at 0, 1, and 6 months--carried out eight years before in 51 dentists.

Fatores prognósticos da doença meningocócica: estudo relativo a 254 casos

Analisa-se, em relacao a 254 casos de doenca meningococica, a variacao da letalidade sob a influencia dos seguintes fatores que, segundo a literatura, agravam-lhe o prognostico: grupos de idade extrema, tempo curto de historia antes da admissao, presenca de purpuras e/ou petequias na admissao, ocorrencia de choque ou de coma, numero de leucocitos normal ou diminuido no sangue periferico na admissao, liquido cefalorraquidiano normal na admissao, numero de leucocitos normal ou diminuido no sangue periferico na admissao, numero de leucocitos menor que 100/mm³, proteinorraquia maior que 300 mg/dl, ou glicorraquia menor que 10 mg/dl, no liquido cefalorraquidiano colhido na admissao. Dentre esses fatores, aqueles para os quais se demonstrou influencia estatisticamente significativa sobre a letalidade foram: 1) idades extremas: maior letalidade em criancas com menos de um ano de idade e em adultos com mais de 40 anos; 2) tempo de historia, antes da admissao hospitalar, menor que 48 horas; 3) presenca de coma ou 4) choque na admissao; 5) numero de leucocitos, no sangue periferico colhido na admissao, igual ou menor que 10.000/mm³. A combinacao desses fatores evidenciou que, quanto maior o numero deles associados, mais alto o indice de letalidade.Two hundred and fifty-four cases of acute meningococcic meningitis at the hospital of the University of Londrina, Parana (Brazil), between 1972 and 1976, were analyzed to determine the lethality of nine prognostic factors, which, according to literature, are said to aggravate the prognosis, namely: age, the period of time the patient has had the disease before admission, petechial and purpuric lesions of the skin, shock, coma, reduced number of leucocytes in peripherical blood, normal cerebrospinal fluid (c.s.f.) on admission, leucocyte number in c.s.f. lower than 100/mm3, protein concentration in c.s.f. higher than 300 mg/dl and glucose concentration in c.s.f. lower than 10 mg/dl (all in c.s.f. obtained upon admission). The following prognostic factors significantly influenced the mortality rate for this disease: 1) extreme ages - greater lethality in children under one year of age and in adults older than 40; 2) if the patient showed signs of the disease less than 48 hours before admission; 3) patient in coma upon admission, or; 4) in a state of shock; 5) leucocytes numbering 10,000/mm3 or lower in peripherical blood obtained upon admission. The combination of these factors showed that the greater the number of associated factors, the higher the mortality rate.

Seroprevalence of Trypanosoma cruzi Infection in Students at the Seven-Fourteen Age Range, Londrina, PR, Brazil, in 1995

Seropositivity for Chagas disease was evaluated in 834 children aged between 7 and 14 from the Municipal Teaching System in the district of Londrina, State of Paraná. A seroprevalence rate of 0.1% was found through the use of an indirect immunofluorescent test and an enzyme-linked immunosorbent assay. This low rate of seroprevalence provides evidence that the vectorial transmission of Chagas disease has been eliminated in Londrina. The main reason for the elimination of vectorial transmission of Trypanosoma cruzi infection, as evaluated by serological tests, may be a remarkable change in the economic structure of the northern region of Paraná in the 1960s. At that time coffee production was almost completely replaced by soy beans, wheat and grazing in the rural areas. This change deeply affected the rural ecology and caused an exodus of the population from rural to urban areas as well as a decrease in the total number of the population of that region. The measures introduced for controlling the disease through the Program of Chagas Disease Control established by the Fundação Nacional de Saúde of the Brazilian Ministry of Health, certainly, had a positive impact on the reduction of American trypanosomiasis prevalence in the area under study. However, it does not seem that this was the most relevant factor responsible for the elimination of vectorial transmission of Chagas disease in Londrina.

Tétano e vacinação antitetânica: estudo na população urbana de Londrian (PR), Brasil

Inquerito realizado em tres grupos da populacao urbana de Londrina (PR), representados por 602 donas-de-casa, 464 colegiais e 778 universitarios, com o objetivo de: determinar o numero de vacinados contra o tetano; avaliar indices de conhecimento sobre o tetano, a vacina e o soro antitetânicos; correlacionar esses indices com algumas caracteristicas de cada grupo da populacao estudada. Concluiu-se que conceitos incorretos e carencia de informacao quanto ao tetano e a vacina antitetânica prevalecem na populacao da zona urbana de Londrina (PR). Foi discutido o significado e a decorrencia desses fatos afirmando-se que a morbidade do tetano, persistentemente elavada no Brasil, deve representar seria advertencia para as autoridades de saude publica em nosso pais, com vista a reformulacao dos programas de vacinacao antitetânica e a revisao dos metodos de educacao sanitaria adotados na divulgacao dessa doenca e dos recursos cientificos disponiveis para sua profilaxia.

Arritmia cardíaca com uso de oxamniquine oral no tratamento de esquistossomose mansônica

Os autores relatam caso clinico de paciente com esquistossomose mansonica, tratado com oxamniquine oral em dose unica de 15 mg/kg, que apresenta como efeito colateral um bloqueio atrio-ventricular incompleto tipo Mobitz I, com parada sinusal e escape ventricular. Concluem que, apesar de a oxamniquine ser eficaz e segura, pode ser determinante de cardiotoxicidade