Patients: pediatric patients with acute appendicitis
Typical features:
(1) age >= 5 years
(2) anorexia present
(3) nausea and/or vomiting present
(4) pain migration present
(5) gradual onset of pain
(6) duration of pain < 48 hours
(7) diarrhea absent
(8) pyrexia present (temperature >= 38°C)
(9) guarding present
(10) percussive tenderness present (or pain with walking or hopping)
(11) decreased bowel sounds
(12) right lower quadrant tenderness
(13) Rovsing's sign present (pressure on the left lower quadrant at a point that mirrors McBurney's point will elicit pain at McBurney's point in the right lower quadrant)
(14) rebound pain present
(15) total white blood cell count >= 10,000 per µL
(16) absolute neutrophil count >= 7,500 per µL (>= 75%)
Almost half of pediatric patients will lack 6 or more of these features.
The strongest evidence against appendicitis is the presence of both:
(1) total white blood cell count < 10,000 per µL
(2) absolute neutrophil count < 7,500 per µL
Additional factors that go against the diagnosis of appendicitis:
(1) absence of percussive tenderness
(2) absence of guarding
(3) absence of nausea and/or vomiting
