Abstract Prostanoid content prostaglandin E2 (PGE2) and thromboxane B2 (TxB2) and endocrine cells population were evaluated in jejunal biopsies from celiac children; findings were compared to active celiac patients on a challenge diet. Patients were divided as follows: Group A: 14 children with active untreated celiac disease; Group B: 7 celiac children on gluten challenge who had received diet therapy for the past 2 years; Group C: 8 normal control children. Jejunal biopsies were used for endocrine cell population measurement by immunocytochemistry, using a specific marker (chromogranin), and for prostanoid radioimmunological evaluation. The quantitative assessment of the endocrine cell population in Groups A and B revealed a significantly higher number of endocrine cells (20 +/- 11.5; 18.4 +/- 9.8 n. cell/visual field respectively) compared to Group C (8.44 +/- 2.3 n. cell/visual field) (p less than 0.05). In the jejunal extract the PGE2 content (341.8 +/- 82.3) ng/g) for Group A biopsies was significantly higher than that of Group C biopsies (93 +/- 23 ng/g) (p less than 0.05. The PGE2 content (69.4 +/- +13.2 ng/g) for Group B did not show any statistically significant change. In contrast, TxB2 content in jejunal biopsies from all three groups was not significantly different.