Clinical presentation

A 46-year-old woman, with a medical history of recurrent urinary tract infections, was admitted to our hospital because of repeated episodes of nausea and vomiting for the last 3 years. Alarm symptoms were absent and physical examination was unremarkable. Upper gastrointestinal endoscopy revealed numerous small nodular lesions (measuring 1–5 mm in diameter) throughout the entire duodenum (figure 1). The stomach was not involved. Extensive biopsies from the nodules were obtained during the procedure (figure 2). Stool antigen test for Helicobacter pylori infection was negative. Laboratory examination showed reduction of IgG and IgA: 3.4 g/L (7.0–16.0), respectively, 0.21 g/L (0.7–4.0). IgM …