++
J. Craig Egan and John J. Aiken
++
Appendicitis is the most frequent pediatric surgical emergency,
and appendectomy is the second most commonly performed pediatric
surgical procedure. The incidence of appendicitis peaks between
10 and 19 years of age.1 In children older than
4 years with an elevated white blood cell (WBC) count, the most
common diagnosis is appendicitis.
+++
Clinical Presentation
and Diagnosis
++
Appendicitis is primarily a clinical diagnosis. The classic history
of periumbilical pain, with anorexia and nausea, followed by localization
of pain in the right lower quadrant is more reliable than right
lower quadrant pain itself for diagnosis.2 Findings
of fever, right lower quadrant tenderness, a Rovsing’s
sign (palpation of the lower left quadrant of a person’s
abdomen results in more pain in the right lower quadrant), or percussion
tenderness with rebound are all highly suggestive of appendicitis.
Right lower quadrant pain during rectal examination may suggest
inflammation of a retrocecal appendix. The pain in appendicitis
is continuous and generally does not get better. The pain is usually present
even when the patient is lying still. Occasionally a child complains
of right lower abdominal pain while walking, or refuses to stand
up or walk.
++
Following the onset of pain, fever, tachycardia, and leukocytosis
are commonly observed. An elevated WBC count or left shift are helpful markers
for the diagnosis of appendicitis in children with nontraumatic
acute abdominal pain.3 The diagnostic accuracy
of the WBC is better than C-reactive protein (CRP), but even when
both are normal, there is a small chance (between 0% and
5%) that appendicitis is present.4
++
An abdominal x-ray might show the presence of an appendix stone
(fecalith) in the right lower area of the abdomen which suggests
that appendicitis may be present (eFig. 413.1),
but a fecalith is only seen on x-ray in a few patients (15%)
so routine abdominal x-ray is not recommended in patients with likely
appendicitis.
++++
The introduction of diagnostic testing including ultrasound and
abdominal computerized tomography (CT) has marginally improved the diagnostic
accuracy for appendicitis. Ultrasound examination is especially
useful in teenage girls in whom gynecology conditions such as an
ovarian cyst are being considered, and in pregnant women. The typical
finding of appendicitis on ultrasound is a round, tender, stiff,
blind-ending structure that is greater than 6 mm in diameter, localized
next to cecum. Abdominal CT can be up to 96% accurate for prediction
of acute appendicitis, with typical findings of an enlarged, swollen
appendix with a thickened wall, periappendiceal standing and often
a ...