What are the next steps in managing a patient with suspected acute appendicitis?

Management of Suspected Acute Appendicitis

The next steps in managing a patient with suspected acute appendicitis should include appropriate imaging (CT with IV contrast for adults, ultrasound for children and pregnant women), followed by appendectomy within 24 hours of diagnosis for most cases, although antibiotic therapy alone may be considered for selected patients with uncomplicated appendicitis. 1

Initial Assessment and Risk Stratification

Clinical Evaluation

• Use clinical prediction scores to stratify patients:
  • AIR (Appendicitis Inflammatory Response) score or AAS (Adult Appendicitis Score) are recommended as they have the highest discriminating power 2
  • Alvarado score is not sufficiently specific to confirm appendicitis in adults 2

Laboratory Testing

• Complete blood count (elevated WBC with left shift)
• C-reactive protein (CRP) (>10 mg/L suggests inflammation)
• The combination of elevated leukocytes, neutrophils, and CRP has a sensitivity of 96% for diagnosing appendicitis 1
• Note: Laboratory tests alone should not be used to confirm or exclude diagnosis 1

Imaging Studies

Adult Patients

• CT scan with IV contrast is the preferred imaging modality (sensitivity and specificity >95%) 1, 2
  • CT without contrast has lower sensitivity (66%) compared to CT with IV contrast (96%) 2
  • Oral or rectal contrast may increase sensitivity but is not always necessary 2

Special Populations

• Children and pregnant women: Ultrasound is the first-line imaging modality 1
• Pregnant women: If ultrasound is inconclusive, MRI is recommended as the secondary option 1
• Immunocompromised patients: Require prompt imaging and early surgical intervention 2

Treatment Options

Surgical Management

• Appendectomy remains the standard treatment for acute appendicitis 2
• Surgery should be performed within 24 hours of diagnosis to minimize complications 1
• Laparoscopic approach is preferred when feasible 2, 1
• Short in-hospital delay (up to 24 hours) is safe for uncomplicated cases 1

Antibiotic Therapy

• All patients diagnosed with appendicitis should receive antimicrobial therapy covering aerobic gram-negative, facultative, and anaerobic organisms 1
• Preoperative antibiotics should be administered 0-60 minutes before surgical incision 1
• For perforated or gangrenous appendicitis, antibiotics should be continued for 3-5 days postoperatively 1

Non-Operative Management

• Antibiotic therapy alone can be considered for selected patients with uncomplicated appendicitis (success rate approximately 70%) 1, 3
• Not recommended for patients with:
  • Appendicolith
  • Appendiceal diameter ≥13 mm
  • Mass effect
  • Signs of perforation 3

Special Considerations

Complicated Appendicitis

• Patients with perforation, abscess, or phlegmon require more aggressive management 4
• Large appendiceal abscesses should undergo percutaneous drainage and antibiotic management 4

High-Risk Patients

• Elderly patients: Higher risk of complications and mortality; require prompt diagnosis and treatment 1
• Children <5 years: Require prompt evaluation due to less specific symptoms and higher perforation risk 1
• Immunocompromised patients: Should undergo appendectomy as soon as possible, usually within 24 hours from diagnosis 2

Common Pitfalls to Avoid

• Do not base diagnosis solely on leukocyte count and CRP 1
• Do not omit imaging studies in women, regardless of clinical presentation 1
• Do not delay preoperative antibiotic administration 1
• Do not perform CT without intravenous contrast in adults 1
• Do not delay surgical consultation in moderate to high-risk patients, as prolonged duration of symptoms increases risk of perforation 5

By following this structured approach to the diagnosis and management of suspected acute appendicitis, clinicians can minimize morbidity and mortality while optimizing patient outcomes.