Relevance of Cat and Dog Sensitization by Skin Prick Testing in Childhood Eczema and Asthma.

BACKGROUND: Household animal dander has been implicated as aeroallergen in childhood atopic diseases. Many parents seek healthcare advice if household pet keeping may be detrimental in atopic eczema (AE), allergic rhinitis and asthma. AIM: We investigated if skin sensitization by cat/dog dander was associated with disease severity and quality of life in children with AE. METHODS: Demographics, skin prick test (SPT) results, disease severity (Nottingham eczema severity score NESS), Children Dermatology Life Quality Index (CDLQI), blood IgE and eosinophil counts of a cohort of AE patients were reviewed. RESULTS: 325 AE patients followed at a pediatric dermatology clinic were evaluated. Personal history of asthma was lowest (20%) in the dog-dander-positive-group but highest (61%) in bothcat- and-dog-dander-positive group (p=0.007). Binomial logistic regression ascertained that catdander sensitization was associated with increasing age (adjusted odds ratio [aOR], 1.056; 95% Confidence Interval [CI], 1.006 to 1.109; p=0.029), dust-mite sensitization (aOR, 4.625; 95% CI, 1.444 to 14.815; p=0.010), food-allergen sensitization (aOR, 2.330; 95% CI, 1.259 to 4.310; p=0.007) and keeping-cat-ever (aOR, 7.325; 95% CI, 1.193 to 44.971; p=0.032); whereas dogdander sensitization was associated with dust-mite sensitization (aOR, 9.091; 95% CI, 1.148 to 71.980; p=0.037), food-allergen sensitization (aOR, 3.568; 95% CI, 1.341 to 9.492; p=0.011) and keeping-dog-ever (aOR, 6.809; 95% CI, 2.179 to 21.281; p=0.001). However, neither cat nor dog sensitization were associated with asthma, allergic rhinitis, parental or sibling atopic status, disease severity or quality of life. CONCLUSION: Physicians should advise parents that there is no direct correlation between AE severity, quality of life, asthma or allergic rhinitis with cutaneous sensitization to cats or dogs. Sensitized patients especially those with concomitant asthma and severe symptoms may consider non-furry alternatives if they plan to have a pet. Highly sensitized individuals, especially those with asthma co-morbidity, may have to remove their pet for a trial period to determine if symptoms improve.

Circulating immunoglobulins, leucocytes and complements in childhood-onset atopic eczema.

OBJECTIVE: To evaluate if eczema severity is associated with blood levels of immunoglobulins, white cell differentials and complements. METHODS: White cell differentials, levels of serum immunoglobulins and complements of patients with eczema and miscellaneous non-eczema skin diseases were measured. Eczema severity and quality of life were assessed by SCORAD, Nottingham Eczema Severity Score (NESS) and Children's Dermatology Life Quality Index (CDLQI). Correlations were analyzed by Pearson's correlation test for parametric data and Spearman's rho correlation test for non-parametric data. RESULTS: Serum IgE and peripheral blood eosinophil percentage were significantly higher in patients with eczema than other non-eczema skin diseases. Levels of IgE (log-transformed), IgA and IgG correlated with objective SCORAD (r = 0.52, 0.40, 0.29, respectively). Levels of eosinophil, neutrophils, lymphocytes and complements also correlated with objective SCORAD, with the eosinohil/lymphocyte ratio showing the highest correlation (r = 0.60, p < 0.01). Ratios of IgE/IgA, IgE/IgG, eosinophils/lymphocytes, eosinophils/neutrophils correlated positively with CDLQI. IgM appeared to have no correlation with eczema. CONCLUSIONS: Blood levels of IgE, IgA, IgG,eosinophils, lymphocytes, neutrophils and complements pathophysiologically correlate with eczema severity. Eosinophil/lymphocyte ratio may represent a readily-available objective laboratory correlate of eczema severity. Eczema is a complex atopic disease involving many cellular and humoral components of the immune system.