Too clean, or not too clean: the hygiene hypothesis and home hygiene.

The 'hygiene hypothesis' as originally formulated by Strachan, proposes that a cause of the recent rapid rise in atopic disorders could be a lower incidence of infection in early childhood, transmitted by unhygienic contact with older siblings. Use of the term 'hygiene hypothesis' has led to several interpretations, some of which are not supported by a broader survey of the evidence. The increase in allergic disorders does not correlate with the decrease in infection with pathogenic organisms, nor can it be explained by changes in domestic hygiene. A consensus is beginning to develop round the view that more fundamental changes in lifestyle have led to decreased exposure to certain microbial or other species, such as helminths, that are important for the development of immunoregulatory mechanisms. Although this review concludes that the relationship of the hypothesis to hygiene practice is not proven, it lends strong support to initiatives seeking to improve hygiene practice. It would however be helpful if the hypothesis were renamed, e.g. as the 'microbial exposure' hypothesis, or 'microbial deprivation' hypothesis, as proposed for instance by Bjorksten. Avoiding the term 'hygiene' would help focus attention on determining the true impact of microbes on atopic diseases, while minimizing risks of discouraging good hygiene practice

Perturbação respiratória durante o sono em doença pulmonar obstrutiva crônica Respiratory disturbance during sleep in chronic obstructive pulmonary disease

A doença pulmonar obstrutiva crônica é uma condição freqüente e é hoje a quarta principal causa de mortes nos Estados Unidos. A prevalência de perturbação respiratória durante o sono, ou síndrome de superposição, como anteriormente denominada, ainda não foi determinada devido à publicação de relatos conflitantes. Esta condição deve continuar sendo investigada devido aos efeitos adversos causados por transtornos respiratórios relacionados ao sono em pacientes com doença pulmonar de base. Neste relato, discutiremos brevemente os mecanismos envolvidos na origem da perturbação respiratória durante o sono em doença pulmonar obstrutiva crônica e auxiliaremos o leitor a distinguir àqueles pacientes que se beneficiariam de uma avaliação do padrão do sono mais detalhada, com a discussão de tópicos de gerenciamento e opções de tratamento.<br>Chronic obstructive pulmonary disease is a prevalent condition and is currently the forth leading cause of mortality in the US. The prevalence of respiratory disturbance during sleep, or overlap syndrome as it was commonly known in the past, is still undetermined as conflicting reports have been published. Because of the adverse effects of sleep-related respiratory impairment in patients with underlying pulmonary disease, this condition deserves further investigation. In this report, we will briefly discuss the mechanisms involved in generating respiratory disturbance during sleep in Chronic Obstructive Pulmonary Disease and will guide the reader into distinguishing those patients who would benefit from a more detailed sleep evaluation, discussing management issues and treatment options