Symptoms of diverticulitis include pain and tenderness, which is generally on the lower left side of the abdomen, bloating, gas, fever, chills, vomiting, nausea and lack of appetite, according to MedlinePlus. Sometimes blood appears in the stool or on toilet paper after a bowel movement.
Short-term pain and tenderness associated with diverticulitis often occurs while eating or a short time after a meal. Long-term symptoms include a change in bowel movements, such as diarrhea or constipation or a bout of both. Usually constipation occurs first, followed by extreme diarrhea. In some cases, these bouts are followed by passing "rabbit pellet" stools. Another long-term symptom of this disorder is dark-purple blood from the rectum, according to NHS Choices.
Diverticulitis develops when the diet is lacking enough fiber, according to Harvard Health. The muscular layer of the colon becomes inflamed when bacteria does not move through the intestinal tract, which causes sacs to protrude. Most of the time the condition is harmless, and it tends to occur in older adults; however, if the damage continues to develop, the infection grows to surrounding tissues. Most of the time, the body can fight serious infections, but sometimes abscesses occur, creating a more complicated condition called peritonitis.