Lower Gastrointestinal Bleeds: False-Negative and False-Positive Tests.

Lower gastrointestinal bleeding in infants and children is a symptom with a broad differential diagnosis. The diagnosis depends on the quantity and quality of the bleeding and on the patient's age. We describe a case of a 10-month-old infant who presented to our pediatric emergency department 4 times with lower gastrointestinal bleeding before a diagnosis of Meckel diverticulum was made. Although this pathology was strongly suspected at an earlier visit, the initial Meckel scan result was interpreted as normal, and the result of a stool test for Clostridium difficile was positive. The case illustrates that repeat scintigraphy might be necessary when significant bleeding is present even if the results of other tests for diagnosis are positive.