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  • • Abdominal pain

    • Anorexia, nausea, and vomiting

    • Localized right lower quadrant pain

    • Low-grade fever

    • Leukocytosis


  • • 7% of people in Western countries have appendicitis at some time in their lives

    • 200,000 appendectomies for acute appendicitis are performed each year in the United States

    • Incidence in developing countries has been increasing in proportion to economic gains and changes in lifestyle

    Major causes: Obstruction of the proximal lumen by fibrous bands, lymphoid hyperplasia, fecaliths, calculi, or parasites

    • Evidence of temporal and geographic clustering of cases has suggested a primary infectious etiology

    • Diagnosis is most difficult in the very young or old

    • Highest incidence of false-positives occur in women between the ages of 20 and 40, attributable to pelvic inflammatory disease (PID) and other gynecologic conditions

Symptoms and Signs

  • • Classically, abdominal pain develops prior to nausea and vomiting

    • Peri-umbilical abdominal pain initially, then localizes to the right lower quadrant

    • Right lower quadrant rebound or percussion tenderness (localized "peritoneal irritation")

    • Constipation and indigestion are frequent complaints

    • Patients complain of discomfort with movement, walking, or coughing

    • Low-grade fever (99 °F-101 °F) unless perforation has occurred

Laboratory Findings

  • • Mild leukocytosis (10,000-15,000) with left shift

    • Mild elevations in amylase

    • UA frequently will show a few WBC and RBCs on microscopic exam

    • Elevated C-reactive protein and ESR levels

Imaging Findings

  • • Plain films may show evidence of localized air fluid levels or localized ileus or increased soft-tissue density in the right lower quadrant

    • -Less common findings include an appendiceal calculus, altered right psoas stripe, or an abnormal right flank stripe

    • US may demonstrate a dilated tubular structure in the right lower quadrant although this technique is user- and institutional-dependant and is less sensitive in adults than in children

    • Spiral CT (either abdominal/pelvic or a dedicated "appendiceal protocol") is the most sensitive and specific diagnostic radiographic test

    • -An enlarged appendix with peri-appendiceal fat stranding is demonstrated in 90-95% of cases

      -CT scans are of greatest value in patients with atypical clinical presentation or laboratory findings

  • • Acute salpingitis

    • PID

    • Regional enteritis/complicated Crohn disease

    • Viral gastroenterologic infection

    • Mesenteric adenitis

    • Dysmenorrhea

    • Ovarian lesions

    • Urinary tract infections

    • Small bowel obstruction

    • Cecal volvulus

    • Incarcerated hernia

    • Mesenteric ischemia

    • Acute cholecystitis

    • Right-sided diverticulitis (true cecal or a redundant sigmoid that flops over into the right lower quadrant)

    • Complicated peptic ulcer disease (with enteric contents collecting in the right paracolic gutter)

    • Infarcted epiploic appendage

Rule Out

  • • Nonsurgical etiology of right lower quadrant abdominal pain

    • -Acute salpingitis


      -Urinary tract infections

      -Viral gastroenterologic infection

      -Mesenteric adenitis


    • Complicated appendicitis manifested by right lower quadrant abscess formation


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