Differential Diagnosis for Intermittent Abdominal Pain in Adolescents

Life-Threatening Causes to Rule Out Immediately

Acute appendicitis is the most common surgical emergency causing acute abdominal pain in adolescents and must be excluded first, classically presenting with periumbilical pain migrating to right lower quadrant, accounting for nearly 50% of emergency presentations with right lower quadrant pain 1
Bowel obstruction from various causes must be evaluated, including adhesions, hernias at umbilical, inguinal, or femoral sites, with pain being classically colicky due to increased peristalsis attempting to overcome obstruction 2, 3
Mesenteric ischemia can occur in adolescents with predisposing conditions, presenting with pain out of proportion to physical examination findings, and has a mortality rate of 30-90% if not diagnosed early 4, 5

Evaluate for hemodynamic instability indicating shock from perforation, ischemia, or severe dehydration, by checking vital signs and assessing for peritoneal signs suggesting perforation or ischemia 3
Examine all hernia orifices and any surgical scars 3
Perform digital rectal examination to detect blood or masses 3
Complete blood count and serum lactate can aid in diagnosis, with leukocytosis suggesting infection or ischemia, and elevated lactate associated with irreversible intestinal ischemia 3, 5

Ultrasound is the first-line imaging for adolescents with moderate-severe pain and localizing findings, with sensitivity and specificity for appendicitis, and avoids radiation exposure 1
CT abdomen/pelvis with contrast should be obtained if ultrasound is non-diagnostic, or if there is clinical suspicion for volvulus, bowel obstruction, or mesenteric ischemia 1, 6