Nesidioblastosis in the neonatal pancreas

A photomicrograph of a stained section through a neonatal pancreas, showing nesidioblastosis. Nuclei are stained blue. This is a rare disease caused by excessive proliferation of islet cells derived from ductular epithelium (ductal stem cells) in the foetus, seen here as the layer of densely staining cells lining the pale triangular ductal area centre bottom of image. The brown-stained cells are neogenic beta-cells. The disease causes hypersecretion of insulin in the neonate, leading to severe persistent profound hypoglycaemia. The pancreas itself usually appears normal on imaging.