Is a HIDA (Hepatobiliary Iminodiacetic Acid) scan appropriate for a patient with mild adenomyomatosis of the gallbladder and right upper quadrant pain, who has already undergone ultrasound?

HIDA Scan for Mild Adenomyomatosis with Right Upper Quadrant Pain

A HIDA scan is appropriate for a patient with mild adenomyomatosis of the gallbladder and right upper quadrant pain who has already completed an ultrasound, especially if the ultrasound findings do not fully explain the patient's symptoms. 1

Diagnostic Algorithm for Adenomyomatosis with RUQ Pain

Initial Evaluation (Already Completed)

• Ultrasound has been performed, showing mild adenomyomatosis
• Patient presents with right upper quadrant pain

Next Steps in Evaluation

1. Laboratory Testing

   • Complete blood count (CBC) to evaluate for leukocytosis
   • Liver function tests (LFTs) to assess for liver abnormalities
   • Pancreatic enzymes to rule out pancreatic pathology
   • Calcium and triglycerides 1

2. HIDA Scan Indication

   • If laboratory tests are normal, a HIDA scan should be performed to confirm gallbladder dysfunction 1
   • HIDA scan is particularly valuable in this case as it can assess functional aspects of the gallbladder that ultrasound cannot evaluate

Clinical Rationale for HIDA Scan

Adenomyomatosis is characterized by hyperplastic changes in the gallbladder wall with formation of Rokitansky-Aschoff sinuses (intramural diverticula) 2. While often asymptomatic, it can cause recurrent right upper quadrant pain 2, which appears to be the case with this patient.

The importance of functional assessment in this case:

• Ultrasound can identify structural abnormalities but cannot assess gallbladder function
• HIDA scan evaluates gallbladder ejection fraction and can determine if the adenomyomatosis is causing functional impairment leading to the patient's symptoms 1
• This functional assessment is crucial for determining if the adenomyomatosis is the actual cause of the patient's pain or if another pathology should be considered

Additional Considerations

Type of Adenomyomatosis

The management approach may vary based on the type of adenomyomatosis:

• Fundal (most common): Can often be monitored with ultrasound if asymptomatic 3
• Segmental: Higher risk of malignancy, may warrant more aggressive evaluation 3
• Diffuse: Can make visualization of coexisting malignancy difficult 3

When to Consider Other Imaging

• If laboratory tests are abnormal, MRCP or CT abdomen should be considered to evaluate the biliary tree and pancreas more thoroughly 1
• MRI may be reserved for cases that remain unclear after ultrasound and HIDA scan, as it can identify Rokitansky-Aschoff sinuses with high sensitivity 4

Common Pitfalls to Avoid

1. Don't assume adenomyomatosis is always asymptomatic

   • While often an incidental finding, it can be the source of right upper quadrant pain 5

2. Don't overlook the need for functional assessment

   • Structural imaging alone may not explain symptoms
   • HIDA scan provides crucial functional information that ultrasound cannot 1

3. Don't miss coexisting pathologies

   • Gallstones frequently coexist with adenomyomatosis and may be the actual cause of symptoms 5
   • HIDA scan can help differentiate between pain caused by adenomyomatosis versus other biliary pathologies

In conclusion, for a patient with mild adenomyomatosis and right upper quadrant pain who has already had an ultrasound, a HIDA scan is an appropriate next step to assess gallbladder function and determine if the adenomyomatosis is the cause of the patient's symptoms.