Severe pain in the right upper quadrant points to a rare anomaly

Miguel, a 33-year-old male, presents to his GP for a recommended follow-up review and further investigation after an ED presentation with right upper quadrant pain, suspected secondary to biliary colic.
The ED discharge states that, at presentation, Miguel had severe right upper quadrant pain radiating to the back, with no associated fever or vomiting.
In ED, his observations were within normal limits, he was not jaundiced but he had right upper quadrant tenderness with a positive Murphy’s sign but no hepatosplenomegaly.
LFTs showed ALP and GGT were slightly raised. FBC, EUC, CRP and lipase were normal, and urine culture was negative.