Very rare disease of small intestine diverticulitis with perforation.At first, the acute diverticulitis is treated in a conservative way. That means a strict diet and the intake of fluids. At the same time, the patient gets broad-spectrum antibiotics, which cover anaerobes and gram-negative bacteria. In case of complications such as peritonitis or the emergence of a fistula, an immediate surgical intervention may be necessary.After the remission of the symptoms, the patient gets a fiber poor diet. When the patient has made a full recovery, he gets a fiber rich diet again.For patients having several episodes of diverticulitis, it is recommended to do a resection of the high pressure zone.This can be done endoscopically or by conventional laparotomy.