Prevalência de anticorpos neutralizantes para o arbovirus Piry em individuos da região de Ribeirão Preto, Estado de São Paulo

Como parte de um inquérito sorológico pesquisando anticorpos para arbovírus, em habitantes da região de Ribeirão Preto, 202 soros foram testados por neutralização em camundongos, para o vírus Piry. Trata-se de um vesículo-vírus (Rhabdoviridae) isolado em Belém do Pará, das vísceras de um marsupial e do sangue de um caso humano. O Piry é causa de doença humana aguda febril. Desconhece-se seus reservatórios animais, vetores e seu ciclo biológico. Os 202 soros testados foram obtidos por venopunção, de moradores adultos em áreas rurais e urbana da cidade de Ribeirão Preto. Os resultados mostraram prevalência de 14,3% de anticorpos neutralizantes para o vírus Piry. Conclui-se que infecções pelo Piry, ou outro agente antigenicamente relacionado, ocorram endemicamente nesta região.

Estudo sobre o diagnóstico laboratorial e sintomas do dengue, durante epidemia ocorrida na região de Ribeirão Preto, SP, Brasil

Uma epidemia de dengue tipo 1 se iniciou em Novembro de 1990 na Região de Ribeirão Preto, Norte do Estado de São Paulo. Foram confirmados por exames laboratoriais cerca de 3.500 casos até fevereiro de 1991. A Unidade de Pesquisa em Virologia da Faculdade de Medicina de Ribeirão Preto - USP, estudou soros de 502 pessoas suspeitas de apresentarem dengue. Fez-se o diagnóstico sorológico através do método da inibição da hemaglutinação (HAI) para dengue tipo 1 em 19% dos analisados. Passou-se a utlilizar um teste imuno-enzimático para dengue em culturas celulares infectadas (EIA-ICC), que permite identificação simultânea de IgG e IgM. O EIA-ICC embora menos sensível quando comparado ao HAI (89%), mostrou-se mais eficiente, porque: dispensou a obtenção de segundas amostras séricas para o diagnóstico; trata-se de técnica simples, podendo ser efetuada em apenas 5 horas. O vírus dengue tipo 1 foi isolado do sangue de 21 pacientes, por inoculação em células de mosquitos C6/36. Fez-se a identificação dos vírus isolados por método de imunofluorescência indireta, utilizando anti-soro contra todos os flavivirus e anticorpos monoclonais tipo-específicos de dengue. Os sintomas mais freqüentemente observados em 71 indivíduos com diagnóstico de dengue confirmado foram febre (90% dos casos), mialgias (57%) e artralgias (41%)

A case of human rabies in the Urban Area of Ribeirão Preto, SP, Brazil

A 39-year old male patient was admitted to the University Hospital of the Faculty of Medicine of Ribeirão Preto with signs and symptoms of sudden dyspnea, generalized myalgia and behavioral disorders. The initial suspicion was alcohol abstinence syndrome and the patient was referred for psychiatric and neurologic care. The evolution of the patient with a worsening of signs and symptoms, presence of crises of tachypnea, agitation, difficulty to swallow, irritability and hydrophobia, and his report of having been bitten by a suspected dog raised the hypothesis of rabies. The diagnosis was confirmed by examination of a corneal impression, biological tests in the cerebrospinal fluid (CSF) and saliva and visualization of Negri bodies in nervous tissue (direct immunofluorescence). The patient evolved with agitation, aggressiveness, and worsening tachypnea intercalating with apnea, and died on the 4th day after admission

Streptococcus pneumoniae and Haemophilus influenzae as etiological agents of conjunctivitis outbreaks in the region of Ribeirão Preto, SP, Brazil

In the study of conjunctivitis outbreaks occurring from September 1994 to September 1996 in the region of Ribeirão Preto, conjunctival exudates of 92 patients were cultivated in Instituto Adolfo Lutz Laboratory I, Ribeirão Preto. Most cases occurred in the age range 2-7 years. The etiological agents which were most frequently isolated from the analyzed cases were: Streptococcus pneumoniae and Haemophilus influenzae, in 40.22% and 21.74%, respectively. 51.35% of the S. pneumoniae isolated strains were not typable. The oxacillin-resistant S. pneumoniae strains were submitted to the minimum inhibitory concentration test (MIC) and three of them presented intermediate resistance, whereas only one was highly resistant to penicillin.

Etiology of acute diarrhea among children in Ribeirão Preto-SP, Brazil

To study the main enteropathogens causing diarrhea in the region of Ribeirão Preto regarding serogroups and serotypes, the feces of 1836 children under 10 years old, from both sexes, attack of acute gastroenteritis, were analysed during a period of 4 years in Adolfo Lutz Institute - Ribeirão Preto, SP. The pathogens identified by standard methods were the following: Escherichia coli, Salmonella spp., Shigella spp., Campylobacter spp., Yersinia spp., and Cryptosporidium spp. Positive samples were 22.8% (419) with 1.7% association of pathogens. Larger isolates were mainly from children 0 to 11 months old. Enteropathogenic E. coli (EPEC) was most frequent (8.7%) with predominance of serogroup O119 (40.2%), followed by Shigella (6.2%), 63.6% of which S. sonnei.

Infective endocarditis (IE) first diagnosed at autopsy: analysis of 31 cases in Ribeirão Preto, Brazil

Thirty one infective endocarditis (IE) fatal cases whose diagnosis was first obtained at autopsy were studied. The clinical data of these patients (Group 1) showed significant differences compared to other 141 IE cases (Group 2). The average age of 53 years in Group 1 patients was 18 years higher than that of Group 2. The Group 1 patients had a low frequency of IE predisposing heart disease. Both patient groups presented fever (about 87%), but a significant low frequency of cardiac murmur (25.8%) was observed in Group 1 patients and echocardiography tests were performed in only 16.1%, suggesting that IE diagnosis was not suspected. Likewise, although most Group 1 patients appeared with severe acute illness, they did not present the classic IE clinical presentation. Blood cultures were performed in only 64.5% of the Group 1 patients. However, bacteria were isolated in 70% of these blood cultures and Staphylococcus aureus was isolated in 71.4%. The bacteria attacked mitral and aortic valves. Complications such as embolizations and cardiac failure occurred in almost half of the cases and they also presented with infections of the lungs, urinary tract, and central nervous system. Medical procedures were performed in practically all fatal cases whose diagnosis was first obtained at autopsy. Sepsis occurred in about half of the patients and it was followed by shock in more than 25%. This form of IE must be suspected in mature and in old febrile hospitalized patients having infection predisposing diseases, embolization, and suffering medical procedures.

Environmental contamination by Toxocara sp. eggs in Ribeirão Preto, São Paulo State, Brazil

Toxocariasis is a zoonosis mainly caused by Toxocara canis, an intestinal nematode of dogs. Man acquires the infection through accidental ingestion of viable eggs, and the toxocariasis clinical manifestations may vary from an asymptomatic infection up to the Visceral Larva Migrans syndrome. Seventy eight public squares of Ribeirão Preto, São Paulo, Brazil, including Bonfim Paulista district were visited aiming to evaluate the soil contamination by Toxocara eggs. The squares were divided in five different areas corresponding to the Sanitary Districts of the city. From May to December 2003, soil samples weighting about 250 g each were collected from five distinct sites of each public square. The laboratorial analysis was done by centrifugal-flotation techniques in magnesium sulphate solutions with 5% of potassium iodide (d = 1.33) and zinc sulphate (d = 1.20), and by the sedimentation- flotation in conic chalices with zinc sulphate (d = 1.20). Toxocara sp. eggs were found on 16 (20.5%) squares, with the lowest prevalence (12%) at the central area. From these results, it is expected that the legal authority will adopt protection measures for the city public areas, reducing thus the contamination risk by Toxocara sp. eggs.

Virulence factors of uropathogenic Escherichia coli from a University Hospital in Ribeirão Preto, São Paulo, Brazil

The aim of the study was to determine the occurrence of virulence genes expressing fimbriae, production of hemolysin, colicin and aerobactin among a hundred Escherichia coli isolates obtained from in-and outpatients of a tertiary-care teaching hospital, between July and August 2000, showing clinical and laboratory signs of urinary tract infection (UTI). The presence of genes (pap, afa, sfa) for fimbriae expression was assayed using specific primers in a polymerase chain reaction. Among the isolates studied, the prevalence of the virulence factors was 96.0%, 76.0%, 24.0%, for hemolysin, aerobactin and colicin, respectively; the prevalence of genes coding for fimbrial adhesive systems was 32.0%, 19.0% and 11.0% for pap, sfa and afa respectively. The strains isolated from the outpatients displayed a greater number of virulence factors compared to those from hospitalized subjects, emphasizing the difference between these two kinds of patients.