Mouse sensitization as an independent risk factor for asthma morbidity

Characteristics of inner-city children with life-threatening asthma

BACKGROUND

Intensive care unit (ICU) admission is a risk factor for fatal asthma. Little is known about risk factors for pediatric ICU admissions for asthma.

OBJECTIVE

To examine characteristics of underserved minority children with prior ICU admissions for asthma.

METHODS

Baseline survey data, salivary cotinine levels, and allergen specific IgE serologic test results were obtained from children with uncontrolled asthma enrolled in a randomized clinical trial of a behavioral education environmental control intervention. Characteristics of children with and without prior ICU admission were compared using χ² and t tests. Logistic regression assessed significance of higher odds of prior ICU admission comparing factor-level categories.

RESULTS

Patients included 222 primarily African American (93.7%), male (56%), Medicaid-insured (92.8%) children with a mean (SD) age of 6.4 (2.7) years with uncontrolled asthma. Most (57.9%) had detectable cotinine levels, 82.6% were sensitized to more than 1 environmental allergen, and 27.9% had prior ICU admissions. Prior ICU patients were more likely to be very poor (<$10,000 per year) and sensitized to more than 1 allergen tested (most importantly mouse) (P < .05). Allergen sensitization in the groups did not differ for cockroach, cat, dog, Alternaria, Aspergillus, dust mite, grass, or tree. Although more ICU patients received combination controller therapy, they also overused albuterol. Only 27.4% of ICU patients received specialty care in the previous 2 years, which was not significantly different from non-ICU patients.

CONCLUSION

Children with high mortality risk, including history of ICU admission, were twice as likely to live in extreme poverty, have atopy (particularly mouse allergen), use combination controller therapy, and overuse albuterol.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01981564.

Allergen sensitization profiles in a population-based cohort of children hospitalized for asthma

RATIONALE

Allergen sensitization is associated with asthma morbidity. A better understanding of allergen sensitization patterns among children hospitalized for asthma could help clinicians tailor care more effectively. To our knowledge, however, sensitization profiles among children hospitalized for asthma are unknown.

OBJECTIVES

We sought to describe allergen sensitization profiles and the distribution of self-reported in-home exposures among children hospitalized for asthma. We also sought to assess how sensitization profiles varied by sociodemographic and clinical factors.

METHODS

This population-based cohort study includes data for 478 children, aged 4-16 years, hospitalized for an asthma exacerbation. Predictors included child age, race, sex, insurance status, reported income, salivary cotinine, exposure to traffic-related air pollution, asthma and atopic history, and season of admission. Outcomes included serum IgE specific to Alternaria alternata/A. tenuis, Aspergillus fumigatus, American cockroach, mouse epithelium, dust mite (Dermatophagoides pteronyssinus and farinae), cat dander, and dog dander (deemed sensitive if IgE ≥ 0.35). Self-reported adverse exposures included mold/mildew, water leaks, cockroaches, rodents, and cracks or holes in the walls or ceiling. Presence of carpeting and furry pets was also assessed.

MEASUREMENTS AND MAIN RESULTS

More than 50% of included patients were sensitized to each of Alternaria, Aspergillus, dust mite, cat dander, and dog dander; 28% were sensitized to cockroach and 18% to mouse. Roughly 68% were sensitized to three or more allergens with evidence of clustering. African American children, compared with white children, were more likely to be sensitized to Alternaria, Aspergillus, cockroach, and dust mite (all P<0.01). White children were more likely to be sensitized to mouse, cat, and dog (all P<0.01). Lower income was associated with cockroach sensitization whereas higher income was associated with dog and cat sensitization (all P<0.01). Atopic history was associated with sensitization to three or more allergens (P<0.01). Although 42% reported exposure to at least one adverse in-home exposure (and 72% to carpet, 51% to furry pets), only weak relationships were seen between reported exposures and sensitizations.

CONCLUSIONS

Most children admitted to the hospital for asthma exacerbations are sensitized to multiple indoor allergens. Atopy on the inpatient unit serves as a potential target for improvement in chronic asthma management.

Sensitization to rodents (mouse/rat) in urban atopic populations without occupational exposure living in Campania district (Southern Italy): a multicenter study

BACKGROUND

Up to now very few data on allergic sensitization to rodent allergens in Western Europe and Italy are available, and there are no information at district level.The aim of this report was to investigate clinical significance and characteristics of allergic sensitization to mouse/rat (M/Rt) allergens in atopic subjects living in Campania district (Southern Italy).

METHODS

Allergists from the whole Campania district were required to report the results of skin prick tests of at least 100 consecutive subjects. In 1,477 consecutive outpatients, we selected all subjects with an immediate skin reaction to M/Rt dander. Clinical history including a careful evaluation of the modality of exposure and the results of skin-prick tests (SPTs) were recorded.

RESULTS

Fifty seven patients were sensitized to M/Rt dander (5.78%). Two patients were mono-sensitized. Fourteen patients reported indoor conditions suggesting presence of rodents allergens at home. All patients exhibited low-moderate degree of SPT positivity to M/Rt. High frequency of concomitant allergic sensitization to dust mites was found.

CONCLUSIONS

Our results suggest that the role of allergic sensitization to rodents is not negligible in atopic subjects without occupational exposure living in Campania district area; these values are higher in comparison to those previously found in Naples area. Highly atopic individuals should be tested by SPTs/evaluation of serum specific IgE to rodents in the case they should begin an occupational exposure to M/Rt or keep these animals as pets.