Parents bring their 24-month-old son to the outpatient clinic after noticing a large amount of maroon-colored stool in his diaper earlier today. The child has no history of fever, abdominal pain, diarrhea, or vomiting. He is currently playing comfortably in the examination room. Vital signs show a heart rate of 105/min, respiratory rate of 24/min, and blood pressure of 90/55 mm Hg. Physical examination reveals a soft, non-tender abdomen with normal active bowel sounds and no palpable masses. Inspection of the perianal area shows no fissures, but residual maroon-colored stool is present on the examining glove. Which of the following is the most appropriate next diagnostic step to establish the underlying cause of this patient's bleeding?
- Technetium-99m pertechnetate scanAnswer
- BAbdominal ultrasonography
- CUpper gastrointestinal endoscopy
- DStool culture and sensitivity
- EDiagnostic contrast enema
Answer
Technetium-99m pertechnetate scan
The patient's presentation of a large volume of painless maroon-colored stool (hematochezia) in an otherwise healthy toddler is the classic clinical picture of a bleeding Meckel diverticulum. Meckel diverticulum is the most common congenital anomaly of the gastrointestinal tract. The bleeding occurs because the diverticulum often contains ectopic gastric mucosa, which secretes acid and causes ulceration of the adjacent unprotected small bowel mucosa. A Technetium-99m pertechnetate scan (often called a Meckel scan) has a high affinity for gastric mucosa and is the most appropriate diagnostic test to identify this ectopic tissue.
Step-by-Step Solution
Key Concept
Meckel diverticulum typically presents in toddlers as painless lower gastrointestinal bleeding and is diagnosed using a Technetium-99m pertechnetate scan to detect ectopic gastric mucosa.
Estimated Time:45s