Opium-related sphincter of Oddi dysfunction causing double duct sign

Area of Science:

• Gastroenterology
• Endocrinology

Background:

• The double duct sign, characterized by simultaneous dilation of the common bile duct (CBD) and pancreatic duct, is typically associated with malignant conditions of the pancreatic head or ampulla.
• Benign etiologies such as chronic pancreatitis or sphincter of Oddi dysfunction (SOD) can also present with a double duct sign.
• Chronic opium abuse is an uncommon cause of the double duct sign, with limited reported endoscopic ultrasound (EUS) findings.

Observation:

• A 54-year-old male with a history of chronic alcohol and opioid abuse presented with recurrent abdominal pain.
• Endoscopic ultrasound (EUS) was performed to exclude malignancy.
• EUS revealed a hypoechoic prominence around the terminal CBD, indicative of hypertrophied muscle.

Findings:

• The patient was diagnosed with opioid-related sphincter of Oddi dysfunction (SOD).
• The double duct sign in this patient was attributed to chronic opium abuse.
• EUS findings suggested hypertrophied muscle around the terminal CBD.

Implications:

• This case underscores that chronic opium abuse can be a rare cause of the double duct sign.
• Opioid-induced SOD is a treatable condition that can mimic more serious pathologies.
• Sphincterotomy provided symptomatic improvement, highlighting its therapeutic role in such cases.