Elevation of IgE in children with sickle cell disease is associated with doctor diagnosis of asthma and increased morbidity

Background: A doctor's diagnosis of asthma is associated with increased morbidity (pain and acute chest syndrome [ACS]) among children with sickle cell disease (SCD). An association between IgE levels and asthma and morbidity has not been investigated in children with SCD. Objective: We tested the hypothesis that elevated total and allergen-specific IgE levels are associated with asthma and SCD morbidity in children with SCD. Methods: A cross-sectional study of children with SCD who participated in the Silent Cerebral Infarct Trial was conducted. Logistic regression and negative binomial regression were used to investigate potential associations of total and allergen-specific IgE levels with asthma diagnosis and SCD morbidity, both confirmed by medical record review. Elevation of total IgE level was defined as age-adjusted and sex-adjusted IgE level exceeding the 90th percentile compared with a nonatopic reference population. IgE antibody positivity to Alternaria alternata (mold), Blattella germanica (cockroach), and Dermatophagoides pteronyssinus (dust mite) was assessed by ImmunoCAP analysis. Results: Children with SCD (140 with asthma; 381 without asthma) were evaluated. Elevations in total IgE level (P = .04) and IgE antibody specific for Alternaria alternata (P = .0003), Blattella germanica (P = .008), and Dermatophagoides pteronyssinus (P = .01) were associated with asthma. ACS (P = .048) but not pain (P = .20) was associated with total IgE level, but neither was associated with specific IgE levels. Conclusion: Significantly increased levels of total and allergen-specific IgE levels are associated with asthma in SCD. High IgE levels are a risk factor for ACS but not pain rates. (J Allergy Clin Immunol 2011;127:1440-6.)