When It’s Not Diverticulitis: Abdominal Conditions Commonly Misdiagnosed in the ER

Every year, thousands of people visit the emergency room with lower abdominal pain, fever, and digestive symptoms. One of the most common diagnoses they walk away with? Diverticulitis.

While diverticulitis is a real and often serious condition, it’s also frequently misdiagnosed—especially in busy ER settings where time is short and imaging results are interpreted under pressure.

At MDView, we help patients get second opinions from radiologists who specialize in abdominal imaging—because when the diagnosis isn’t right, the treatment won’t be either.

What Is Diverticulitis?

Diverticulitis occurs when small pouches in the colon wall, called diverticula, become inflamed or infected. It typically causes:

  • Left lower abdominal pain
    Fever
    Nausea or vomiting
    Changes in bowel habits

A CT scan is usually used to confirm the diagnosis. However, here’s the catch: many other abdominal and pelvic conditions can look like diverticulitis on a CT scan, especially to a general radiologist.

Conditions Commonly Mistaken for Diverticulitis

1. Colon Cancer

  • Why it’s confused: Both can cause bowel wall thickening and fat stranding on CT.

  • Risk of misdiagnosis: Cancer may be missed if assumed to be inflammation.

  • When to suspect cancer: Recurrent “diverticulitis,” weight loss, or age over 50 without a recent colonoscopy.

2. Inflammatory Bowel Disease (IBD)

  • Includes Crohn’s disease and ulcerative colitis.

  • Symptoms overlap: Diarrhea, fever, abdominal pain, and colonic wall thickening.

  • Clue: Chronic symptoms, younger patients, or involvement beyond the sigmoid colon.

3. Ischemic Colitis

  • Caused by reduced blood flow to the colon.

  • Why it mimics diverticulitis: Also causes pain and inflammation, especially in older adults.

  • Clue: Sudden onset, risk factors like heart disease or clotting disorders.

4. Infectious Colitis

  • Pathogens like C. difficile, E. coli, or viruses can inflame the colon.

  • Common CT findings: Thickened colon wall and surrounding fat stranding.

  • Clue: Recent antibiotic use or travel, profuse diarrhea.

5. Pelvic Inflammatory Disease (PID)

  • In women, PID can cause pain in the same area as diverticulitis.

  • Clue: Vaginal discharge, menstrual irregularities, and tenderness on pelvic exam.

6. Ovarian Cysts or Torsion

  • Adnexal masses or ovarian torsion can mimic diverticulitis on imaging.

  • Clue: Right or left lower quadrant pain in women, often without GI symptoms.

7. Appendicitis (with an unusual location)

  • A retrocecal or long appendix can present pain in the left lower abdomen.

  • Clue: Pain that started in the center and moved, or a history of atypical symptoms.

Why the ER May Get It Wrong

Emergency rooms are fast-paced. Radiologists often read CT scans without the benefit of a full clinical history or prior imaging for comparison, and radiologists who are on call to read ER scans often shift context rapidly between very different types of exams, which increases cognitive load and the risk of errors, especially subtle ones. 

That’s where a second opinion from a sub-specialized focused body imaging radiologist can make all the difference.

How a Second Opinion Can Help

At MDView, we connect you with board-certified radiologists who specialize in the exact type of scan you had, abdominal CTs included. Each abdominal CT uploaded to MDView is matched ONLY to radiologists who specialize in body imaging radiology, which focuses on imaging of the abdomen, pelvis, and chest. You’ll receive a detailed report from an expert in Abdominal CTs within 72 hours or less, often with findings your original radiologist may have missed.

Get clarity on whether you truly have diverticulitis
Rule out colon cancer or other serious conditions
Avoid unnecessary antibiotics, hospital stays, or procedures

Get a Second Opinion on your CT

If you were told you have diverticulitis, especially if it was diagnosed in the ER, it’s recurrent, or something just doesn’t feel right, a second opinion report on the imaging exam you already had is a smart step. Misdiagnoses happen, but with expert review, you can take back control of your care.

MDView: Clarity. Confidence. Control.
Request your second opinion today from a radiologist who specializes in abdominal imaging. Simply upload your exam to see the eligible radiologists who are experts in your exam. Don't have your exam? No problem! MDView can get your exam on your behalf at no cost to you directly from the facility! 


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