Workup for Persistent Right Abdominal Pain After Prior CT
For a patient with persistent right abdominal pain years after a previous CT scan, repeat imaging with CT abdomen/pelvis with IV contrast is the most appropriate next step, as the prior imaging is outdated and cannot exclude interval development of pathology.
Initial Assessment Priorities
The key clinical question is whether this represents chronic functional pain versus an evolving organic process that has developed since the prior imaging. Your immediate focus should be on:
- Red flag symptoms: Fever, weight loss, change in bowel habits, bloody stools, or progressive worsening of pain intensity 1
- Pain characteristics: Constant versus intermittent, relationship to meals, movement-related pain (suggests abdominal wall origin) 2
- Physical examination findings: Localized tenderness, peritoneal signs, palpable mass, or pain that increases with abdominal wall muscle tensing (Carnett's sign) 2
Imaging Strategy
For Right Upper Quadrant Pain
Start with abdominal ultrasonography (rated 9/9 by ACR), not CT, as the initial imaging modality 3. Ultrasound is:
- Most appropriate for detecting biliary pathology (cholecystitis, cholelithiasis)
- Radiation-free and readily available
- Can identify alternative causes of right upper quadrant pain 3
If ultrasound is inconclusive, proceed to:
- CT abdomen with IV contrast (rated 6/9) for surgical planning or equivocal findings 3
- Cholescintigraphy (HIDA scan) if acute cholecystitis is suspected (96% sensitivity, 90% specificity) 3, 4
- MRI with and without contrast for hepatobiliary abnormalities not characterized on ultrasound 3
For Right Lower Quadrant or Nonlocalized Right-Sided Pain
CT abdomen and pelvis with IV contrast is the primary imaging modality 3, 4. This approach provides:
- 95% sensitivity and 94% specificity for appendicitis 4
- Detection of right colonic diverticulitis (8% of right lower quadrant pain cases) 4
- Identification of bowel obstruction (3% of cases), inflammatory bowel disease, infectious enterocolitis, and ureteral stones 4
Always use IV contrast unless contraindicated, as noncontrast CT will miss critical diagnostic features 4. Consider contrast-enhanced low-dose CT to reduce radiation exposure while maintaining diagnostic accuracy 3.
Important Clinical Caveats
When CT May Not Be the Answer
Abdominal wall pain: If pain increases with abdominal muscle tensing or is localized to a circumscribed tender point, this suggests musculoskeletal origin 2. These patients often have pain in the semilunar line (71% of cases), linea alba, or along the costal arch 2. This diagnosis avoids repeated costly investigations 2.
Biliary pathology: CT has only ~75% sensitivity for gallstones because 80% are noncalcified and isodense to bile 4. For suspected biliary disease, ultrasound remains first-line 4.
If Initial Imaging is Negative
When cross-sectional imaging is normal but pain persists:
- Consider MRI abdomen/pelvis as an alternative with high accuracy for various intra-abdominal pathologies (99% overall accuracy in one study) and no radiation exposure 3
- Exploratory laparoscopy is recommended for progressive or persistent pain after negative imaging to establish or exclude diagnoses 3
- Avoid repetitive testing once functional pain is established; refer for psychological support and symptom-directed pharmacotherapy 1
Special Considerations
The elderly and immunocompromised patients may present with atypical symptoms and normal laboratory values despite serious infection 3. Maintain a lower threshold for imaging in these populations 3.
The two-year interval since prior imaging is clinically significant—conditions like inflammatory bowel disease, malignancy, chronic diverticulitis, or adhesive disease could have developed in the interim, making historical imaging inadequate for current evaluation 3, 1.