Salivary cotinine levels in children presenting with wheezing to an emergency department.

We set out to evaluate salivary cotinine concentrations to judge tobacco smoke exposure among infants and children, and to examine the results in relation to age and wheezing. This was a case-control study of wheezing children (n = 165) and children without respiratory tract symptoms (n = 106) who were enrolled in the Pediatric Emergency Department at the University of Virginia. The age range of both wheezing and control patients was 2 months to 16 years. Questionnaires were combined with cotinine assays in saliva to evaluate exposure to environmental tobacco smoke (ETS) for each child. The prevalence of exposure to one or more smokers at home was high (68%); and 43% of the children enrolled were exposed to ETS from their mothers. According to the questionnaires, and after adjusting for age and race, a wheezing child in this study was more likely than a control to be exposed to at least one smoker at home (odds ratio = 1.9; 95% CI = 1.1-3.4). However, the odds of exposure to ETS from smoking mothers did not differ significantly between wheezing and control patients, and no significant association was found between the presence of wheezing and salivary cotinine levels. Among children exposed to ETS at home, cotinine levels were significantly higher in saliva from those under the age of two years, and from toddlers aged 2 and 3 years, compared to values from children over age 4 years. Moreover, the number of smokers in the home strongly influenced cotinine levels from children under age 4 years. In addition, higher cotinine levels were observed in saliva from children under age 2 years who were exposed to ETS from their mothers. Cotinine levels were similar and significantly correlated in paired samples of saliva and serum from children under 4 years of age (n = 54), (r = 0.92, P < 0.001). Based on information gathered from questionnaires, the results indicate that wheezing children were more likely than controls to be exposed to ETS at home. However, significant differences in ETS exposure between wheezing and control groups with respect to maternal smoke exposure or comparisons of salivary cotinine levels were not apparent. It was clear that determinations of salivary cotinine for monitoring the prevalence and intensity of household smoke exposure in this study were most valuable during the first 4 years of life.

Markers of mast cell degranulation.

Mast cells are the primary effector cells of immediate hypersensitivity reactions in humans. Upon mast cell activation both preformed and newly synthesized mediators are secreted. Histamine can be measured by fluorometric assays, radioenzymatic assays, and immunoassays. These methods have been applied to plasma and urine to detect histamine that had been released in vivo and to release histamine in vitro from basophils and mast cells. Another mast cell constituent is tryptase, which is a more selective marker of mast cells, because negligible amounts are found in basophils. beta-Tryptase is stored in secretory granules and is actively released when mast cells degranulate. alpha-Protryptase remains in the proenzyme form and is constitutively released from mast cells, and consequently its level in serum reflects total numbers of mast cells. alpha-Protryptase levels are elevated in serum at baseline in subjects with systemic mastocytosis, whereas beta-tryptase is elevated in serum from subjects with systemic anaphylaxis. These markers serve as precise clinical indicators of the involvement of mast cells in human disease.

Epidermal Langerhans' cells and their function in the skin immune system.

OBJECTIVE: This article reviews the role of the epidermal Langerhans' cell in contact dermatitis and atopic dermatitis. Included in this review are sections on the historical, morphologic, immunohistochemical, and electron microscopic aspects of the Langerhans' cell. Differences between freshly isolated and cultured Langerhans' cells are reviewed in terms of cell surface markers and functional differences. The different IgE binding structures on the surface of Langerhans' cells are reviewed with discussion of their possible roles. The effects of different cytokines in the microenvironment are also commented upon. Other diseases where the Langerhans' cell is important such as histiocytosis X, HIV-1 infection, and skin graft rejection are briefly reviewed. DATA SOURCES: English literature search (1974-1994), indexing terms: Langerhans' cells, atopic dermatitis, IgE. STUDY SELECTION: The purpose of this paper is to review the most recent knowledge of Langerhans' cell function and relate this to the allergist/immunologist. RESULTS/CONCLUSIONS: Epidermal Langerhans' cells play a central role in the immune response in exhibiting multiple cell-surface receptors and secreting a variety of cytokines that are important in the pathogenesis of contact dermatitis, atopic dermatitis, histiocytosis X, HIV-1 infection, and skin graft rejection.

Retention of pit and fissure sealant on the primary molars of 3- and 4-year-old children after 1 year.

An investigation of pit and fissure sealant retention in 1,871 children in the Head Start program was conducted in Tennessee in September 1985 to determine the retention of the sealant after application to the occlusal surfaces of primary molars of 3- and 4-year-old children. The investigation shows pit and fissure sealants are retained on primary molars at a rate comparable to that expected on permanent molars.