Chronic Left-Sided Abdominal Pain with Negative Workup
Consider Functional or Visceral Pain Syndrome
For a 50-year-old woman with 1–2 months of left-sided pain and completely negative CT, labs, EGD, and colonoscopy, the most likely diagnosis is chronic visceral hypersensitivity or functional abdominal pain rather than ongoing structural disease. Approximately 45% of patients report persistent abdominal pain at 1-year follow-up after acute diverticulitis, usually due to visceral hypersensitivity rather than ongoing inflammation 1.
Immediate Next Steps
Re-evaluate for Missed Diagnoses
Obtain a detailed pain characterization: location (left upper vs. lower quadrant), quality (sharp, cramping, burning), radiation pattern, timing (constant vs. intermittent), aggravating/relieving factors (meals, bowel movements, position), and associated symptoms (bloating, altered bowel habits, urinary symptoms, gynecologic symptoms) 2.
Review the CT report specifically for: pericolonic lymph nodes >1 cm (which may suggest malignancy mimicking inflammatory disease), mesenteric pathology, gynecologic abnormalities, renal/ureteral pathology, and abdominal wall abnormalities 1, 3.
Confirm the CT was contrast-enhanced: Non-contrast CT can miss early diverticulitis, mesenteric ischemia, and subtle inflammatory processes 4, 1.
Exclude Extra-Abdominal Causes
Consider musculoskeletal/abdominal wall pain: Palpate for trigger points, assess for pain with Valsalva or straight-leg raise, and consider diagnostic nerve blocks if localized tenderness is present 1.
Rule out referred pain: Inferior myocardial infarction, pneumonia, and pulmonary embolism can present as upper abdominal pain, particularly in elderly patients 5.
Diagnostic Workup for Persistent Symptoms
Laboratory Re-assessment
C-reactive protein (CRP): A level >140 mg/L indicates significant inflammatory disease that may have been missed 1, 6.
Complete blood count: Assess for anemia (suggesting occult GI bleeding or malignancy) or persistent leukocytosis 7, 2.
Stool studies: If diarrhea or altered bowel habits are present, test for ova and parasites, Clostridioides difficile, and fecal calprotectin (elevated in inflammatory bowel disease) 3.
Advanced Imaging if Indicated
Repeat CT abdomen/pelvis with IV contrast: Only if new symptoms develop, significant time has passed, or the initial CT was non-contrast 3.
MRI abdomen/pelvis: Consider if CT was equivocal or if there is concern for gynecologic pathology (endometriosis, adenomyosis) or early inflammatory bowel disease 4, 3.
Ultrasound (transvaginal): First-line for premenopausal women when gynecologic pathology (ovarian cyst, endometriosis) is suspected 1.
Management of Chronic Post-Inflammatory Pain
If No Active Inflammation is Found
Treat visceral hypersensitivity: Low-to-moderate dose tricyclic antidepressants (e.g., amitriptyline 10–25 mg at bedtime, titrated to effect) are effective for chronic abdominal pain without inflammation 1, 6.
Reassure the patient: Explain that persistent pain after resolved inflammation is common and does not indicate ongoing disease or cancer 1.
Avoid unnecessary repeat imaging: Repeated CT scans increase radiation exposure and rarely change management in the absence of new symptoms 1.
Lifestyle and Dietary Modifications
High-fiber diet: ≥22 g/day from fruits, vegetables, whole grains, and legumes reduces recurrence risk if prior diverticulitis was present 1, 6.
Avoid NSAIDs and opioids: Both are associated with increased risk of diverticulitis and can worsen chronic pain 6.
Regular physical activity: Vigorous exercise decreases diverticulitis risk and may improve functional pain 1, 6.
Specialist Referrals
Gastroenterology Consultation
Indications: Persistent symptoms despite conservative measures, concern for inflammatory bowel disease (Crohn's disease can mimic diverticulitis), or need for repeat colonoscopy if >5 years since last exam 3.
Colonoscopy timing: If complicated diverticulitis was previously present (abscess, perforation), repeat colonoscopy 6–8 weeks after resolution is mandatory to exclude colorectal cancer (7.9% prevalence in complicated cases) 1, 6.
Pain Management or Psychiatry Consultation
- Psychosocial evaluation: Psychological factors influence pain perception and treatment outcomes; consider referral if pain is refractory to medical management 1.
Red Flags Requiring Urgent Re-evaluation
New fever, severe pain (≥8/10), or inability to tolerate oral intake: Obtain repeat CT to assess for complications (abscess, perforation, obstruction) 1, 6.
Unintentional weight loss, iron-deficiency anemia, or rectal bleeding: Urgent colonoscopy to exclude malignancy 1, 3.
Signs of bowel obstruction: Vomiting, inability to pass gas/stool, severe distension—requires immediate surgical consultation 3.
Common Pitfalls to Avoid
Do not assume negative imaging rules out all pathology: CT cannot replace colonoscopy for mucosal lesions, and early inflammatory bowel disease may not be visible on CT 1.
Do not prescribe antibiotics without evidence of infection: CRP <140 mg/L, normal WBC, and negative CT make bacterial infection unlikely 1, 6.
Do not overlook gynecologic causes in women: Endometriosis, ovarian cysts, and pelvic inflammatory disease can present as chronic left-sided pain 1, 2.
Do not delay colonoscopy if age-appropriate screening is overdue: Colorectal cancer can present with chronic pain and normal labs 1, 3.