Emerging eosinophilic (allergic) esophagitis: increased incidence or increased recognition?
BACKGROUND
Eosinophilic esophagitis is a disease of the esophagus with distinct histologic features (prominent intraepithelial eosinophils, particularly superficial with clustering) and characteristic endoscopic features (trachealization, white plaques). The presence of intraepithelial eosinophils had been recognized since 1982 as indicative of reflux esophagitis but little attention was initially paid to their numbers or location. Eosinophilic esophagitis has been recently described and there have been a number of reports that its incidence is on the rise. It had been our impression that eosinophilic esophagitis was being seen more frequently, perhaps resulting from some environmental change.


OBJECTIVE
To investigate the increased prevalence of eosinophilic esophagitis.


METHODS
We analyzed a similar group of cases from 2005 (n = 150) as compared with 1990 (n = 115). Consecutive patients with mucosal esophageal biopsies from May through June of the respective years were included in the analysis. Patients with Barrett metaplasia or with carcinoma were excluded. The highest density of intraepithelial eosinophils for each patient was recorded as the number of intraepithelial eosinophils per single high-power field. The patients were categorized by the number of intraepithelial eosinophils per high-power field with those cases with greater than 20 intraepithelial eosinophils per high-power field representing eosinophilic esophagitis.


RESULTS
There was no difference in the incidence of eosinophilic esophagitis between 1990 and 2005.


CONCLUSIONS
The apparent increased incidence of eosinophilic esophagitis is largely a result of an increase in recognition rather than an increase in disease resulting from an environmental factor.
Vanderheyden
Andrew D
AD
Department of Pathology, University of Iowa, Iowa City, USA.
Petras
Robert E
RE
DeYoung
Barry R
BR
Mitros
Frank A
FA
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004802:Eosinophilia / Q000453:epidemiology* / Q000473:pathology; D004941:Esophagitis / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000473:pathology; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged