Eosinophilic gastroenterocolitis in iron lactate-overloaded rats

Eosinophilic gastroenterocolitis with peripheral eosinophilia was induced i n rats fed a diet containing 2.5% or 5.0% iron lactate for 3 mo. Additional findings consistent with iron overload were also observed. Microscopically , the lesions consisted of eosinophilic infiltrations in the mucosa and sub mucosa along the whole length of the gastrointestinal tracts, increased sur face area of the gastric mucosal propria covered with mucous cells, and inc reased apoptotic bodies in the gastric glandular neck of rats in the 2.5% a nd 5.0% groups. An increased number of intraepithelial globule leukocytes i n the gastric and intestinal lamina propria was also observed in the 5.0% g roup. Globule leukocytes in the gastric mucosa contained obviously enlarged granules in their cytoplasm in these rats. The granules of the globule leu kocytes were positive for rat mast cell protease II, suggesting the mastocy te origin of these cells. Although severe infiltration of eosinophils and g lobule leukocytes suggested a type-1 hypersensitivity reaction, other featu res such as an increasing vascular permeability were not detected. Serum Ig E levels in the 5.0% and control groups were <3 ng/ml. Final body weights o f male and female rats of the 5.0% group were suppressed to 70% and 90%, re spectively, of those of the control rats, whereas food consumption was comp arable to that of the control group. The morphologic characteristics of the gastrointestinal lesions and peripheral eosinophilia induced in rats fed i ron lactate were very similar to those in some cases of eosinophilic gastro enterocolitis in humans and other animals.