Umbilical Varices: A Potential Pitfall in Gastrointestinal Bleed Scintigraphy Interpretation

Area of Science:

• Nuclear Medicine
• Gastroenterology
• Radiology

Background:

• Tc-99m labeled red blood cell (RBC) scintigraphy is a standard imaging modality for acute gastrointestinal (GI) bleeding.
• GI bleeding typically presents as focal radiotracer uptake that intensifies and migrates with bowel segments on serial imaging.

Purpose of the Study:

• To report a case of GI bleeding where umbilical varices mimicked active hemorrhage on Tc-99m RBC scintigraphy.
• To emphasize the utility of SPECT-CT in differentiating umbilical varices from true GI bleeding.

Main Methods:

• A patient with recurrent GI bleeding underwent Tc-99m labeled RBC scintigraphy.
• Initial dynamic imaging revealed a focal abdominal hot spot.
• Subsequent static and SPECT-CT imaging were performed for further characterization.

Main Results:

• The focal hot spot identified on initial dynamic images was determined to be umbilical varices on SPECT-CT.
• Umbilical varices often exhibit prompt filling, potentially leading to false-positive interpretations of hemorrhage.
• SPECT-CT provided definitive localization and characterization, avoiding misdiagnosis.

Conclusions:

• Promptly filling umbilical varices can be a source of false-positive findings in Tc-99m RBC scintigraphy for GI bleeding.
• SPECT-CT is crucial for accurate differentiation of umbilical varices from actual hemorrhage.
• Integrating SPECT-CT can prevent misinterpretation and guide appropriate patient management.