A man with abdominal pain and eosinophilia : tissue is the issue

A 24-year-old male presented with abdominal pain, postprandial vomiting and weight loss. Lab results showed an elevated serum eosinophil count and CT-scan demonstrated a thickened antral, duodenal and jejunal wall. Repetitive endoscopic mucosal biopsies were normal. Work-up of eosinophilia-associated gastro-intestinal disorders excluded secondary causes. Bone marrow showed an elevated eosinophil count without arguments for a primary hypereosinophilic syndrome. Endoscopic ultrasound-guided fine needle biopsy detected a strongly elevated number of eosinophils in the muscularis layer of the duodenum. The diagnosis of muscularis- predominant eosinophilic gastroenteritis together with a secondary hypereosinophilic syndrome was made. The patient was started on steroids and all symptoms vanished within a few days. (Acta gastroenterol. belg., 2019, 82, 532-535).