Evaluation of site-specific and seasonal variation in colonic mucosal eosinophils.

Several systemic disorders and gastrointestinal diseases may be associated with increased colonic mucosal eosinophils, which may vary in number throughout the normal colon. Some investigators have proposed that colonic eosinophilia reflects allergen exposure, although this hypothesis has never been validated, and values quantifying the number of mucosal eosinophils that can be regarded as a normal finding are lacking. The aims of this study were to determine the number of intramucosal eosinophils normally present throughout the colon and evaluate the relationship between colonic eosinophilia and seasonal allergen exposure. Eosinophils in the crypt epithelium and lamina propria were evaluated in 198 mucosal biopsy specimens obtained from the ascending (n = 98) and descending (n = 100) colon of patients with normal colonoscopic examinations. The cases were stratified into 12 groups, reflecting the months during which the samples were obtained, and the mean number of mucosal eosinophils was determined for each group. Daily air pollen counts were recorded, and the mean determined for each month. Fifty-five percent of mucosal biopsy specimens from the ascending colon contained eosinophils in the crypt epithelium, compared with only 5% of biopsy specimens from the descending colon (P < .001). Lamina propria eosinophils were, on average, 3 times more numerous in the ascending compared with the descending colon (P < .001). Mucosal eosinophils were slightly more numerous in samples obtained in April and May, corresponding to periods of highest pollen counts, but this relationship was not significant (P > .05). We conclude that intramucosal eosinophils are commonly present in the proximal colon but show only mild fluctuations with ambient allergen exposure.

Differences in race, ethnicity, and socioeconomic status in schoolchildren dispensed injectable epinephrine in 3 Massachusetts school districts.

BACKGROUND: Published surveys depicting the increase in the incidence of food allergy, especially peanut or tree nut allergy, in children have not reported any differences in race, ethnicity, or socioeconomic status. OBJECTIVE: To analyze the demographics of schoolchildren with diverse racial, ethnic, and socioeconomic characteristics dispensed injectable epinephrine. METHODS: School nurses in 44 schools enrolling 21,875 students recorded the characteristics of students dispensed injectable epinephrine in the 2003-2004 school year. Surveyed school districts included 2 affluent suburban districts enrolling 5,855 students (> 92% white) and 1 urban district enrolling 16,020 students (60% nonwhite). RESULTS: A total of 181 students in all 3 districts were dispensed injectable epinephrine; 118 of these children had peanut or tree nut allergy. Males were more likely to be dispensed injectable epinephrine than females (odds ratio [OR], 1.44; P < .02). Whites were more likely to have been dispensed injectable epinephrine than nonwhites (OR, 4.76; P < .001). Whites were nearly 5 times more likely to be dispensed injectable epinephrine for peanut or tree nut allergy than nonwhites (OR, 4.5; P < .001). Most students (75%) dispensed injectable epinephrine for peanut or tree nut allergy were enrolled in prekindergarten through grade 5 (P < .001). Whites were more likely than nonwhites to be dispensed injectable epinephrine for stinging insect allergy (OR, 8.7; P < .001). CONCLUSIONS: This study found significant racial, ethnic, and socioeconomic differences in the prevalence of childhood allergic disorders, especially peanut or tree nut allergy, requiring prescribed injectable epinephrine in a school setting. Additional studies are needed to determine whether minority children are being underdiagnosed or undertreated for allergic disorders requiring injectable epinephrine or whether they truly have a lower incidence of such allergic disorders.