Can you interpret the abdominal imaging of a menopausal woman with intermittent left-sided abdominal pain that worsens with walking, is associated with constipation, and has no fever, nausea, vomiting, or urinary symptoms, and a history of urinary tract infections?

Imaging Recommendation for Left-Sided Abdominal Pain in a Postmenopausal Woman

For this postmenopausal woman with intermittent left-sided abdominal pain associated with bowel symptoms and constipation, obtain a CT abdomen and pelvis with IV contrast as the initial imaging study to evaluate for diverticulitis and other gastrointestinal, gynecologic, and urologic causes. 1, 2

Rationale for CT with IV Contrast

The clinical presentation—left lower quadrant pain in a postmenopausal woman with bowel-related symptoms and constipation—creates a broad differential diagnosis that requires comprehensive evaluation:

• CT abdomen and pelvis with IV contrast is rated as "usually appropriate" (rating 9/9) for suspected diverticulitis and provides 98% overall accuracy 2
• CT with IV contrast demonstrates 89% sensitivity versus 70% for ultrasound in adults with abdominopelvic pain 1
• The IV contrast specifically improves detection of bowel wall abnormalities, pericolic inflammation, abscesses, and vascular pathology 2, 3

Why This Patient Needs Imaging

While the pain has been intermittent for a year, several factors warrant imaging now:

• No prior imaging-confirmed diagnosis of the pain etiology
• Age-appropriate screening considerations: Last colonoscopy 8 years ago (overdue for repeat screening)
• Postmenopausal status changes the differential: In this population, ovarian cysts account for 33% of gynecologic causes, uterine fibroids are the second most common cause, and ovarian neoplasm occurs in 8% of cases 1
• Gastrointestinal causes predominate in postmenopausal women with left lower quadrant pain, particularly diverticulitis 2, 4

Specific Differential Diagnoses to Evaluate

The CT will assess for:

Gastrointestinal Causes (Most Likely)

• Diverticulitis: Most common cause of left lower quadrant pain; CT sensitivity/specificity 95% 5
• Colonic pathology: Given 8 years since last colonoscopy, malignancy must be excluded
• Epiploic appendagitis: Self-limited but mimics diverticulitis
• Fecal impaction/severe constipation: Can cause intermittent pain

Gynecologic Causes

• Ovarian cysts: Account for one-third of gynecologic pain in postmenopausal women 1
• Degenerating fibroids: Second most common gynecologic cause in this age group 1
• Ovarian neoplasm: 8% of gynecologic pain cases 1

Urologic Causes

• Urolithiasis: Given history of UTIs during menopause
• Hydronephrosis: Can occur from mass effect

Alternative Imaging Considerations

Ultrasound is NOT recommended as initial imaging in this case because:

• Lower sensitivity (70%) compared to CT (89%) for urgent diagnoses 1
• Limited evaluation of bowel pathology
• Cannot adequately assess for diverticulitis complications
• Operator-dependent and less commonly used in the U.S. for non-gynecologic left lower quadrant pain 3

MRI is NOT appropriate for initial evaluation because:

• More time-consuming
• Less sensitive for extraluminal air
• Subject to motion artifacts in symptomatic patients
• Not useful for acute abdominal pain evaluation 3

Plain radiography is inadequate as it cannot diagnose diverticulitis or characterize masses 2, 3

Critical Pitfalls to Avoid

1. Do not assume this is purely functional bowel disease despite the chronic intermittent nature—the 8-year gap since colonoscopy and postmenopausal status mandate structural evaluation
2. Do not order ultrasound first thinking this is gynecologic—the bowel-related symptoms and left-sided location make GI pathology more likely
3. Do not defer imaging until after the cruise—undiagnosed diverticulitis or other pathology could become complicated during travel
4. Do not skip IV contrast unless contraindicated—unenhanced CT has lower accuracy for bowel wall pathology and cannot adequately characterize masses 3

Follow-Up Considerations

After imaging:

• If diverticulitis is confirmed, colonoscopy should be performed 6-8 weeks after symptom resolution to exclude underlying malignancy 5
• If imaging shows ovarian mass, gynecology referral is needed
• The scheduled October gastroenterology appointment remains appropriate for colonoscopy regardless of CT findings, given the 8-year interval

The CT should be obtained before the cruise to ensure safe travel and appropriate management of any identified pathology.