Why despite the lower prevalence, is asthma more severe in the semiarid region?

INTRODUCTION AND OBJECTIVES: Asthma is a chronic inflammatory disease which is very prevalent throughout the world, and climatic factors, especially air humidity, have been considered fundamental to its development. This study aims to evaluate the relationship between the climate factor and the severity of asthma episodes in the semiarid region, comparing it to the coast and an intermediate climate region, considering the use of medication as an intervening factor. MATERIALS AND METHODS: Ecological study in cities with different climatic conditions (semiarid, intermediate region and Coast). Prevailing data was obtained from the International Study of Asthma and Allergies in Childhood (ISAAC) protocol. We evaluated the temperature, humidity and use of drugs for asthma/100,000 inhabitants. RESULTS: The prevalence of asthma was lower in the semiarid (14%; 95%CI=12.1-15.7) than the intermediate region (19.1%; 95%CI=17.7-20.6) and coast (17.9%; 95%CI=16.6-19.2). Episodes of severe asthma attacks were surprisingly higher in semiarid (10.4%; 95%CI=8.9-11.9) when compared to coast (4.1%; 95%CI=3.4-4.9) and intermediate region (5.0%; 95%CI=4.3-5.8). In the semiarid region, the humidity was lower and the temperature higher than the other cities evaluated. The dispensing of medications was lower in the semiarid region. CONCLUSIONS: Temperature and humidity may have contributed to a lower prevalence and greater severity of asthma in the semiarid region. The dispensing of medications was lower in the semiarid region, indicating that access to both relief and control drugs was lower in this city. The possibility of lack of health care in the semiarid region can also be another explanatory factor associated.

Immunological studies and in vitro schistosomicide action of new imidazolidine derivatives

Schistosomiasis is a major public health problem with 207 million people infected and more than 779 million at risk. The drug of choice for treating schistosomiasis is praziquantel (PZQ); however, it is inefficient against immature forms of schistosomes. The aim of this study was to test new imidazolidine derivatives LPSF/PT09 and LPSF/PT10 against adult Schistosoma mansoni worms. IC50, cytotoxicity, immune response and cell viability assays were also available for these imidazolidines. Different concentrations of imidazolidine, from 32 to 320 »M, promoted motor abnormalities in breeding and unpaired worms, and death in 24 hours at higher concentrations. Although LPSF/PT09 and LPSF/PT10 did not affect IFN-³ and IL-10 production, they induced nitric oxide production and showed a similar behavior to praziquantel on cell death test. Thus, these new imidazolidine derivatives should undergo further study to develop schistosomiasis drugs.

Sensitisation to aeroallergens among asthmatic and non-asthmatic adolescents living in a poor region in the Northeast of Brazil.

OBJECTIVES: To assess the kind and frequency of sensitisation to aeroallergens (skin prick test - SPT) of asthmatic and non-asthmatic adolescents (13-14 years old) living in the city of Caruaru, Northeast of Brazil, and to analyse their exposure to some environmental factors. METHOD: A case-control study was conducted with asthmatic (50) and non-asthmatic (150) adolescents diagnosed by the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire. All were submitted to SPT with aeroallergens (house dust mites, cat and dog epithelium, cockroaches, moulds and grass) and completed a questionnaire to evaluate their environmental exposure. RESULTS: There were no significant differences between groups regarding gender, age, number of siblings and environmental exposure. Asthmatic subjects exhibited a higher frequency of positive SPTs than non-asthmatic subjects (54.0% vs 33.3%, p=0.009) mainly due to Periplaneta americana (34.0% vs 12.7%, p=0.0007 respectively) and Canis familiaris (20.0% vs 8.7%, p=0.029). CONCLUSION: Although sensitisation to aeroallergens was high among non-asthmatic adolescents, asthma was associated with parental history of atopic disease and sensitisation to P. americana and Canis familiaris but not to D. pteronyssinus showing that local studies are mandatory for the tailoring of appropriate management of allergic diseases.

[Risk factors for neonatal death in Recife: a case-control study] / Fatores de risco para óbitos neonatais no Recife: um estudo caso-controle.

OBJECTIVE: Neonatal mortality is the main cause of infant mortality in the city of Recife. The objective of the present study was to determine the major risk factors for neonatal death in Recife in 1995. METHODS: This is a case control study. Information was obtained from the mortality and live birth databases after validation of the data set, between January and December 1995. A sample of 456 cases and 2,280 controls was obtained after using the linkage technique between the two data sets. The difference in proportion was analyzed by the chi square test. The odds ratio was calculated as a risk measure, with a 95% confidence interval. The logistic regression technique was used to adjust potential confounding factors. RESULTS: 212 deaths (46.6%) occurred in the first 24 hours of life. We found that 358 (79.7%) of the cases presented low birth weight, with a 46-fold higher risk of death (CI =33.8-59.0 P<0.001) than those weighing >/= 2,500g. The major risk factors observed in the logistic regression analyses of the measure, listed in descending order, were: birth weight < 1,500g (OR= 49.6 CI= 22.6-108.7 P<0.001), 5-minute Apgar score < 7 (OR = 44.1 CI= 25.1-77.2 P<0.001), birth weight between 1,500 and 2,500g (OR= 8.2 CI= 4.8-14.0 P<0.001), gestational age < 37 weeks (OR= 4.3 CI= 2.6-7.1 P<0.001). CONCLUSIONS: Among the studied variables, birth weight, gestational age, and Apgar score should be considered the main risk factors for the surveillance of neonatal death.

[Risk factors for childhood asthma in Fernando de Noronha: a case control study]. / Fatores de risco para asma infantil em Fernando de Noronha: estudo do tipo caso-controle.

Fernando de Noronha Island, because of its ecological characteristics,has virtually no atmospheric pollution that could cause asthma. Nevertheless, asthma prevalence in children younger than 6 years old is 11.22%. 17 asthmatic children and 68 healthy ones were included in this case control study (1:4 case/controls) conducted in a closed community free from atmosphere pollution. Maternal asthma and exposure to smoking were more frequently associated with asthmatic children than with controls, the risk of asthmatic syndrome being respectively 6.9 and 4.6 times bigger. As for breastfeeding no protective effect was found in both cases and controls.

A study of the importance of the enterotoxigenic E. coli in children with acute diarrhoea in Recife, Brazil.

Even today acute diarrhoea is a major cause of morbidity and mortality in young children. It is a serious public health problem in less-developed countries, primarily in households whose income is low. As such, it is one of the main causes of death, affecting the undernourished in particular. The potential enteropathogenic agents are distributed universally. However, there is a major difference in the prevalence, according to the areas and the characteristics of the population groups which were studied. In Brazil, since the 1970s, our attention has been drawn to the importance of the classic enteropathogenic strains of E. coli (EPEC) in the aetiology of diarrhoeal diseases, primarily those present in weaned infants in inner city neighbourhoods. On the other hand, Guerrant and co-workers, and Queiroz and co-workers found significant percentages of isolated colonies of enterotoxigenic coli (ETEC) in the stool material of children with symptoms of acute diarrhoea. In rural areas of less-developed countries the incidence of episodes of ETEC provoking diarrhoea is estimated to be between five and ten per person/year. Due to the social and medical gravity of acute diarrhoea, and to the lack of studies dealing with the aetiopathogenic role of the strains of ETEC in our area, we decided to analyse the frequency of isolation of ETEC in children with and without diarrhoea who were attending the out-patient department of the Instituto Materno Infantil de Pernambuco/IMIP.