What is the appropriate management for a patient presenting with right lower quadrant (RLQ) pain?

Management of Right Lower Quadrant Pain in Adults

CT abdomen and pelvis with IV contrast is the imaging modality of choice for adult patients presenting with right lower quadrant pain, demonstrating 95% sensitivity and 94% specificity for appendicitis while also identifying alternative diagnoses that frequently require hospitalization or invasive treatment. 1

Initial Clinical Assessment

When evaluating RLQ pain, recognize that while appendicitis is the most common surgical pathology, approximately 50% of emergency department presentations with RLQ pain have alternative etiologies including right colonic diverticulitis, ureteral stones, colitis, and intestinal obstruction. 1

Key clinical pitfall: Do not rely on clinical examination or scoring systems like the Alvarado score alone—the negative appendectomy rate based on clinical determination without imaging reaches an unacceptably high 25%. 1

Red Flag Assessment

If the patient presents with RLQ pain PLUS right thigh weakness, this requires urgent evaluation for psoas abscess or retroperitoneal pathology rather than typical appendicitis. 2 This combination suggests:

• Iliopsoas muscle involvement causing hip flexion weakness and pain with hip extension 2
• Possible lumbar plexus compression (L2-L4 nerve roots) 2
• Potential femoral neuropathy from compression or inflammation 2

Imaging Algorithm

Primary Imaging: CT Abdomen and Pelvis with IV Contrast

CT is usually appropriate as initial imaging because it:

• Identifies appendicitis with 95% sensitivity and 94% specificity 1
• Detects alternative diagnoses including retroperitoneal collections, psoas abscesses, diverticulitis, and gynecologic pathology 1, 2
• Provides sensitivities of 85.7-100% and specificities of 94.8-100% for acute abdominal pathology 2

MRI Considerations

MRI with diffusion-weighted imaging (DWI) sequences demonstrates excellent performance with specificities and positive predictive values of 100%, and sensitivities/negative predictive values of 97-99% for appendicitis. 1 DWI combined with T2-weighted images provides higher accuracy, and inflamed appendix shows lower apparent diffusion coefficient values than normal appendix. 1

Management Based on Imaging Results

If Appendicitis Confirmed

Proceed directly to appendectomy as standard treatment. 2

For perforated appendicitis with abscess:

• Initiate broad-spectrum antibiotics immediately 2
• Percutaneous catheter drainage is usually appropriate for collections >3 cm 2
• Consider delayed surgery or drainage-only approach 2

If Psoas or Retroperitoneal Abscess Identified

• Start broad-spectrum antibiotics immediately 2
• Percutaneous catheter drainage is usually appropriate for collections >3 cm 2
• Critical pitfall: Do not delay imaging when thigh weakness is present—psoas abscesses can rapidly progress to sepsis 2

If CT Shows Only Stool/No Acute Pathology

Conservative management is appropriate when CT excludes surgical emergencies. 3 Among patients with negative CT findings:

• Only 14% require hospitalization 3
• Only 4% need surgical or image-guided intervention 3

Recommended conservative approach:

• Initiate bowel regimen with stool softeners and/or osmotic laxatives 3
• Provide symptomatic pain relief with appropriate analgesics 3
• Reassess clinical status within 24-48 hours 3

Monitor for red flag symptoms requiring reimaging:

• Fever, persistent vomiting, worsening pain 3
• Peritoneal signs or inability to tolerate oral intake 3
• Clinical deterioration or new concerning features 3

Avoid unnecessary repeat imaging in patients whose symptoms are improving or stable, as this increases radiation exposure without changing management. 3

Alternative Diagnoses to Consider

Beyond appendicitis, CT frequently identifies conditions requiring specific management including inflammatory and infectious conditions of the ileocecal region, diverticulitis, malignancies, epiploic appendagitis, omental pathology, mesenteric conditions, constipation, gastroenteritis, colitis, benign adnexal masses, and inflammatory bowel disease. 3, 4, 5

Critical Management Pitfalls

• Never assume appendicitis based solely on RLQ pain and fever—thigh weakness or other atypical features are red flags for alternative pathology 2
• Do not dismiss persistent pain that fails to improve with conservative management—consider patient-specific factors and alternative diagnoses 3
• Increased imaging utilization decreases negative appendectomy rates without increasing perforation rates from diagnostic delays 1