Lower gastrointestinal bleeding in a newborn caused by isolated intestinal vascular malformation

We report a 3-week-old neonate with an intestinal vascular malformation. The usual investigations performed for the examination of lower gastrointestinal bleeding had negative results, but ultrasound revealed bowel loops of abnormal calibre and altered flow in the superior mesenteric artery. Ultrasound should be considered a diagnostic study of primary importance when assessing a neonate with gastrointestinal bleeding.