Brunner's gland hyperplasia in the sand rat (Psammomys obesus)

Brunner's glands are submucosal glands located in the proximal duodenum. Hyperplasia of the Brunner's gland has been reported rarely in humans and animals. We examined sections of the Brunner's gland from 63 sand rats submitted for necropsy over 2 years. Of the 63 animals necropsied, 45 (71%) had evidence of hyperplasia defined as nodular expansion, dilated ducts, or intraductal papillary proliferation. The hyperplasia was graded as mild in 22 (49%) of the cases, moderate in 15 (33%), and marked in 8 (18%). We found an association with both increased age and evidence of gastric ulceration and hyperplasia of the Brunner's gland. In sand rats with marked hyperplasia, 8 of 8 (100%) had evidence of gastric ulceration, compared to 13 of 18 (72%) in animals with no hyperplasia. Animals with marked hyperplasia were, on average, 8.4 months older than animals with no hyperplasia. There was no association with gender. The lesion in sand rats is histologically similar to that in humans.