A 5-year-old boy is brought to the physician for a 1-day history of increasingly severe right lower abdominal pain. Vitals are within normal limits. He has not had diarrhea or vomiting. Abdominal examination shows tenderness to palpation of the right lower quadrant. There is no guarding, rebound, or masses. Laboratory studies show:
Hemoglobin 9.0 g/dL
Mean corpuscular volume 70 μL
Leukocytes 9,000/μL
Which of the following is most likely to confirm the diagnosis?
Abdominal CT scan
Abdominal ultrasound
Examination for stool ova and parasites
Laparoscopy
Peripheral blood smear
Voiding cystourethrogram
