The relationship between seroatopy and symptoms of either allergic rhinitis or asthma.

BACKGROUND: Epidemiologic data on allergic rhinitis and asthma are frequently based on self-reported symptoms. OBJECTIVE: This cross-sectional study examined the relationship between self-reported symptoms and histories of allergic rhinitis or asthma and a marker of allergic sensitization, allergen-specific IgE. METHODS: We surveyed 702 pregnant women in Michigan. Blood samples were analyzed for specific IgE to 9 allergens: dust mites (Dermatophagoides farinae and Dermatophagoides pteronyssinus), cat, dog, cockroach, ragweed, timothy grass, egg, and Alternaria alternata. Seratopy was defined as a specific IgE greater than or equal to 0.35 kU/L to any allergen. RESULTS: Seroatopy was found in 66.7% of those with hay fever symptoms, 68.3% with a physician's diagnosis of asthma, and 72.1% of those with both conditions. These results differed significantly from asymptomatic subjects, where 49.8% of patients without hay fever and 50.4% without asthma were seroatopic. Race and education did not modify the relationships. Symptoms related to specific exposures were modest predictors of positive specific IgE to related allergens (positive predictive values from 26.5% to 50.3%). CONCLUSION: Self-reported symptoms of allergic rhinitis or asthma were significantly associated with allergic sensitization, but the odds ratios were of relatively low magnitude for this historical information to be considered evidence of current allergic sensitization. A 66% to 68% probability existed that those with symptoms of allergic rhinitis or asthma would have a positive specific IgE test. CLINICAL IMPLICATIONS: Self-reported histories of hay fever or asthma alone are only modest predictors of allergic sensitization. When knowledge of allergic sensitization is important, information beyond self-reported symptoms is necessary.

Ontogeny of the allergic inflammatory response.

The ability to produce allergic responses begins early in fetal life along with the development of other elements of the immune system. Among the most interesting questions related to the development of allergic disease are whether the fetus in utero commonly is exposed to sufficient allergen to induce IgE production and how much the mother's immune responses affect the developing fetal immune system. After birth, it seems that many factors, including the frequency and severity of infections and the timing and intensity of allergen and animal exposures, continue to influence immune development.