ABSTRACT
Recently, several authors have documented that respiratory infections may cause wheezing and acute exacerbation of asthma in children. Respiratory syncytial virus infections have been recognized to produce the first episode of wheezing in children who go on to develop chronic asthma. Furthermore, repeated infections caused by other common childhood viral pathogens have been proposed to affect responses of the immune system in such a way as to prevent the onset of allergic diseases and possibly asthma. Recently, it became clear that also infections by intracellular pathogens, such as Chlamydia and Mycoplasma, may cause acute and chronic wheezing in some individuals. In this review we describe the immunologic and clinical implications of the association between respiratory infections and asthma.
Subject(s)
Asthma/etiology , Chlamydophila pneumoniae , Pneumonia, Mycoplasma , Respiratory Sounds/etiology , Respiratory Syncytial Viruses , Respiratory Tract Infections/complications , Acute Disease , Antibody Formation , Asthma/immunology , Asthma/microbiology , Asthma/virology , Child , Chronic Disease , Cytokines/immunology , Humans , Immunity, Cellular , Respiratory Sounds/immunology , Respiratory Tract Infections/immunology , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/virologyABSTRACT
Several studies have emphasized the role of familial factors and familial aggregation in increasing susceptibility to obstructive sleep apnea syndrome (OSAS); the aim of the present study was to investigate the possible influence of human leukocyte antigen (HLA) in the development of sleep disordered breathing and OSAS of children. Between January 2000 and January 2003, all the 370 children [193 males; median age: 5.2 years (range: 1-12 years)] with sleep disordered breathing referred to our Center were screened by a 41-item multiple-choice questionnaire. All habitual snores children underwent a polisomnographic evaluation, and those with an apnea/hypopnea index >3 were diagnosed as having OSAS. All children with OSAS or primary snoring were HLA typed for class I and II. According to nocturnal polygraphic monitoring study, 41 patients were diagnosed as having OSAS and 32 as primary snoring. Patients in the two diagnostic groups were homogeneous for demographic and clinical characteristics. HLA-B65 was found to be significantly more expressed in children with sleep disordered breathing as compared with controls (10.5% versus 3.61; Pypc < 0.04) while no difference was found for the other tested antigens. A logistic regression analysis found cough (P < 0.02) and persistent wheeze (P < 0.008) the sole risk factors for OSAS development. Our preliminary data suggest that HLA does not play a key role in the pathogenesis of OSAS, however more studies are needed to clarify this issue.
