Differential Diagnosis for Diverticulitis

The following differential diagnosis is organized into categories to help guide the thought process:

• Single Most Likely Diagnosis

  • Diverticulitis: This is the most likely diagnosis given the presentation of abdominal pain, tenderness, and possible changes in bowel habits, which are all characteristic symptoms of diverticulitis. The diagnosis is often confirmed by imaging studies such as CT scans.

• Other Likely Diagnoses

  • Irritable Bowel Syndrome (IBS): Although IBS typically presents with chronic abdominal pain and changes in bowel habits without an inflammatory cause, it can sometimes be considered in the differential due to overlapping symptoms.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can present with similar symptoms to diverticulitis, including abdominal pain and changes in bowel habits, but are typically distinguished by chronicity, presence of blood in stool, and specific findings on endoscopy and biopsy.
  • Gastroenteritis: An infection of the intestines caused by bacteria, viruses, or parasites, which can present with acute onset of abdominal pain, diarrhea, and vomiting.

• Do Not Miss Diagnoses

  • Appendicitis: Although the pain of appendicitis typically starts near the navel and then moves to the lower right abdomen, it can sometimes present atypically, especially in older adults or those with an atypical appendix location. Missing appendicitis can lead to perforation and severe complications.
  • Ectopic Pregnancy: In women of childbearing age, ectopic pregnancy can present with abdominal pain and must be ruled out due to its potential for severe and immediate complications.
  • Intestinal Obstruction: This condition, which can be caused by various factors including adhesions, hernias, or tumors, presents with severe abdominal pain, vomiting, and obstipation (inability to pass gas or stool). It requires prompt diagnosis and treatment to prevent bowel ischemia and necrosis.
  • Mesenteric Ischemia: A condition where there is a blockage of one or more of the major arteries that supply blood to the intestine, leading to ischemia and potentially necrosis of the bowel tissue. It presents with severe abdominal pain out of proportion to physical findings and is a medical emergency.

• Rare Diagnoses

  • Epiploic Appendagitis: Inflammation of one of the epiploic appendages (small, fat-filled pouches) attached to the colon, which can mimic diverticulitis in its presentation.
  • Omental Infarction: Also known as omental thrombosis or torsion, this is a rare cause of acute abdominal pain that can be mistaken for other conditions like diverticulitis or appendicitis.
  • Colonic Carcinoma: Although not typically presenting with acute abdominal pain, a colonic tumor can cause intermittent obstruction or intussusception, leading to abdominal pain and changes in bowel habits.