Gastrointestinal Pathology I Case Studies


CASE 5: Acute appendicitis


Clinical History:

A 20-year-old woman presented to the emergency room with only a one day history of lower abdominal pain, nausea with anorexia, and fever. On physical examination, there was periumbilical pain. Under active observation over the next couple of hours, the pain migrated to the right lower quadrant, with rebound tenderness. Her vital signs showed T 38.5 C, P 90, R 18, and BP 110/70 mm Hg. Her WBC count was 11,500 with 76% polys, 6% bands, 14% lymphs, and 4% monos. A pregnancy test was negative. A stool sample was negative for occult blood. A urinalysis was normal. The radiographic finding on abdominal CT scan is seen in image 5.1. A laparoscopic procedure was performed and the gross appearance of the lesion is shown in image 5.2. The microscopic appearance is seen in images 5.3 and 5.4.
  1. What diagnosis do you suspect?

    2. Acute appendicitis. This is a common condition, with a lifetime risk of 7%, and though most cases occur in younger persons, the disease has a wide age range from infancy to old age. As a person ages, the appendiceal lumen often becomes obliterated, explaining the decreasing incidence with age.

  2. What should be done next?

    3. Ultrasonography, laparoscopy and computed tomography (CT) can be used to clarify the diagnosis in patients under active observation for whom a firm diagnosis of appendicitis has not been made. If appendicitis is suspected, then the patient should have an appendectomy performed. There is no medical therapy for acute appendicitis.

  3. What is seen prominently in the tissue section?

    4. There is acute inflammation with many neutrophils. The mucosa is focally eroded. The inflammation extends through the wall and appears on the serosa. The serositis accounts for much of the abdominal pain.

  4. What could happen if this is not promptly treated?

    5. The wall of the appendix could rupture, producing an acute peritonitis and/or abscess. The patient could become septic and die. The complication of rupture is more likely to occur in the very young and old, when the diagnosis is not suspected and/or when diagnosis is delayed. Since there is about a 2% mortality associated with appendiceal perforation, surgeons err on the side of fase positive diagnosis with acute appendicitis (about 1 in 5 or 1 in 10 removed will be normal pathologically).