Differential Diagnosis for Gallbladder Polyp

The following differential diagnoses are considered based on the provided ultrasound findings:

• Single most likely diagnosis
  • Gallbladder polyp: The ultrasound finding of a focal prominence from the wall into the lumen, measuring 0.64 cm, is highly suggestive of a gallbladder polyp. The lack of other abnormalities such as wall thickening or intraluminal echoes supports this diagnosis.
• Other Likely diagnoses
  • Cholesterol polyp: A type of gallbladder polyp that is usually small and asymptomatic, which could explain the finding.
  • Inflammatory polyp: Although less likely given the absence of wall thickening, an inflammatory polyp could still be a consideration.
  • Adenomatous polyp: A type of polyp that has the potential for malignant transformation, although the small size (0.64 cm) makes this less likely.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Gallbladder cancer: Although the polyp is small and the gallbladder wall is not thickened, gallbladder cancer can occasionally present as a polypoid lesion. Clinical correlation and potentially further imaging or follow-up are crucial.
• Rare diagnoses
  • Metastasis to the gallbladder: Extremely rare, but could present as a polypoid lesion. The absence of other findings and the small size of the polyp make this unlikely.
  • Gallbladder leiomyoma: A rare benign tumor of the gallbladder that could present as a polyp.
  • Heterotopic tissue (e.g., gastric or intestinal mucosa): Rarely, heterotopic tissue can be found in the gallbladder and might appear as a polyp on ultrasound.

Given the findings, a gastroenterologist or a general surgeon would be the most appropriate specialists to consult for further evaluation and management of the gallbladder polyp. Additionally, if there's a suspicion of malignancy or the need for further imaging, a radiologist might also be involved.