Patients rarely have the “classic” presentation of appendicitis. Frequently it is misdiagnosed as GASTROENTERITIS!!!

Three Stages of Appendicitis

  • Stage 1: ~12 hours of “gastroenteritis” like symptoms
  • Stage 2: Direct somatic irritation
    • This is when pain over McBurney’s develops!
  • Stage 3: Perforation
    • Patient is now sick and septic

Approach to Appendicitis

  • Step 1: Consider getting labs
    • Always remember “The white blood cell count is the last refuge of the intellectually destitute”
    • The WBC count has both low sensitivity and low specificity for acute appendicitis
  • Step 2: Get a detailed history
    • When did the pain start?
      • How many HOURS into their syndrome are they (remember stages of appendicitis)
      • Is the pain migrating?
    • Objective fever?
    • Did the pain start before the vomiting started?
    • Does the patient have decreased appetite?
  • Step 3: Perform a physical exam
    • Pain over McBurney’s point
      • Right lower quadrant
      • 1/3 the distance from the ASIS to the umbilicus
    • Peritoneal signs (Rigidity, Rebound, Guarding)
    • Psoas sign
      • Lie patient on left side with legs extended
      • Extend their hip behind them
      • Pain = Suspected retroperitoneal inflammation
    • Obturator sign
      • Have patient lie on back with hip/knee flexed at 90 degrees
      • Internally rotate hip (move ankle away from body)
      • Pain = Suspected obturator internus inflammation
  • Step 4: Imaging
    • Most adults
      • CT scan +/- IV contrast
    • Pregnant women
      • MRI abdomen
    • Pediatric patients
      • RLQ ultrasound
  • Step 5: Disposition
    • Perform a repeat abdominal exam
    • Even if CT is negative, consider followup in ED in 12-24 hours

Additional Reading