What is the initial investigation recommended for diagnosing Meckel's diverticulum?

The initial investigation recommended for diagnosing Meckel's diverticulum is a radioisotope scan, also known as a Meckel's scan. This imaging technique is specifically designed to detect ectopic gastric mucosa, which is often present in patients with Meckel's diverticulum. During this scan, a small amount of radioactive material is injected into the bloodstream. If gastric tissue is present in the diverticulum, it will absorb the radioactive material, allowing for visualization on the scan.

This method is especially useful because it is non-invasive and can accurately identify the presence of Meckel's diverticulum, which is a common cause of gastrointestinal bleeding in children. The specificity of the radioisotope scan for gastric mucosa makes it particularly effective compared to other imaging modalities for this condition.

In contrast, while ultrasound can be useful in evaluating abdominal pain in children, it is less sensitive for detecting Meckel's diverticulum. MRI is generally not a first-line investigation for pediatric gastrointestinal conditions due to its cost and availability, and X-rays are insufficient on their own, as they can miss the diverticulum and do not provide specific information about the gastric mucosa. Thus, the radioisotope scan stands out as the most appropriate initial diagnostic tool