A previously healthy 10-year-old girl is brought to the emergency department because of a 2-day history of increasingly severe abdominal pain. She has had anorexia for the past day. She has no history of serious illness and does not take any medications. Her temperature is 38.5°C (101.3°F), pulse is 105 beats/min, blood pressure is 95/65 mm Hg, and respirations are 20/min. On physical examination, she appears well developed and well nourished. Cardiopulmonary examination shows no abnormalities. Abdominal examination shows localized tenderness over the left lower quadrant, and there is guarding at McBurney’s point. Bowel sounds are decreased. Laboratory studies show a leukocyte count of 15,000/mm3 and hemoglobin concentration of 13.0 g/dL. Urinalysis shows no abnormalities.
D) Surgical evaluation
Appendicitis refers to acute inflammation of the appendix and usually results from appendiceal obstruction by a fecalith or lymphoid hyperplasia. Appendiceal obstruction leads to bacterial proliferation within the lumen and wall of the appendix, eventually leading to inflammation, infection, appendiceal necrosis, and perforation. Acute appendicitis typically presents with abdominal pain that is periumbilical at onset and may later migrate to the right lower quadrant, along with leukocytosis and tenderness to palpation. Bacterial proliferation causes leukocytosis, such as in this patient which is predominantly neutrophilic. Patients often develop fever and may also experience nausea and anorexia. Multiple scoring systems exist to stratify cases into low, moderate, or high risk for appendicitis. Imaging with CT scan, MRI, or ultrasonography can assist in diagnosis. Low risk cases can be discharged home (if there is no right lower quadrant tenderness) or with reevaluation in 12-24 hours (if there is right lower quadrant tenderness). Moderate risk cases typically benefit from imaging. High risk, or classic cases such as this one, require surgical evaluation. This is usually done before imaging to minimize radiation exposure as well as minimize delay. Treatment involves administration of intravenous antibiotics and operative intervention, typically laparoscopic appendectomy, to prevent appendiceal rupture, which can lead to peritonitis or an intra-abdominal abscess.
Answer Choice A: Admission to the hospital for observation and serial examinations, is incorrect. This patient presents with classic features of appendicitis and no clear alternative diagnosis, so the best next step is surgical evaluation.
Answer Choice B: CT scan of the abdomen, is incorrect. While CT scan of the abdomen can be helpful in diagnosing equivocal cases of appendicitis, it is associated with the risk for radiation exposure, which is a consideration, especially in a pediatric patient.
Answer Choice C: Measurement of serum C-reactive protein concentration, is incorrect. C-reactive protein (CRP) is an inflammatory marker that, while potentially increased in acute appendicitis, is nonspecific. It can be elevated in a variety of inflammatory conditions, and measurement would neither confirm nor rule out the diagnosis of appendicitis. While appendicitis is a clinical diagnosis, equivocal or uncertain cases can be further evaluated with imaging such as ultrasonography, CT scan, or MRI.
Answer Choice E: Ultrasonography of the abdomen and pelvis, is incorrect. Ultrasonography of the abdomen and pelvis can help confirm a diagnosis of appendicitis. However, further confirmation of diagnosis with a CT scan or ultrasonography should not delay operative evaluation and intervention in a patient with a clear clinical diagnosis of appendicitis and no other source of fever with a negative urinalysis.
Key Learning Point
High risk or classic cases of appendicitis require surgical evaluation which should not be delayed to pursue imaging.
