Ileosigmoid knot.

The ileosigmoid knot (ISK) is a variant of midgut volvulus in which a loop of ileum wraps around the base of an elongated sigmoid colon and passes beneath itself forming a knot. A long small bowel mesentery and a sigmoid colon on a narrow pedicle are necessary prerequisites, but the wide variation in incidence of ISK across the world seems to be related to dietary habits. Rapid fluid resuscitation, preoperative broad-spectrum antibiotics, methylprednisolone in the presence of shock, and immediate laparotomy may improve the high mortality.