A child with unexplained etiology of acute pancreatitis diagnosed by endoscopic ultrasound.

A 3-year-old child presented with severe abdominal pain radiating to back. His investigations revealed high serum amylase and lipase levels, normal biochemistries and ultrasound abdomen. An endoscopic ultrasound (EUS) was done (with endobronchial ultrasound, Pentax eb-1970 UK), it showed a linear echogenic structure with central linear anechoic defect completely filling pancreatic duct (PD) suggestive of Ascaris as shown in Figure 1a and 1b. It was removed with the help of Dormia basket. The child had rapid recovery.

Figure 1

Endoscopic ultrasound image showing a linear echogenic structure with central lucency completely filling pancreatic duct (a, b in different panels)

DISCUSSION

Ascaris lumbricoides is the most common helminthic infection in the world. While intestine is normal habitat of adult worm, occasionally these worms migrate to biliary or PDs. Biliary ascariasis is an uncommon cause of abdominal pain or obstructive jaundice in nonendemic regions, but it is a common cause of pancreatobiliary disease in an endemic region. Biliary symptoms (pain, and cholangitis) are more common than acute pancreatitis.[12] Migration of worm in the bile duct is more common than PD, probably due to a smaller size of PD, in a series of 500 pancreatobiliary ascariasis, only seven cases had pancreatic ascariasis.[2] In a study form Kashmir (endemic area for ascariasis in India), Ascaris was etiologic factor in 59/256 (23%) cases of acute pancreatitis. Of these 59 cases, 51 patients had a worm in the bile duct, four in PD and four in both ducts.[3] Ascaris appears as four lines sign in PD on ultrasound.[4] On EUS, Ascaris lumbricoides appears as long echogenic structure with central anechoic linear defect, without producing shadow effect [Figure 2, common bile duct Ascaris].[5] Ascaris induced pancreatitis is generally mild and worm extraction is associated with rapid relief of symptoms.[3]

Figure 2

Endoscopic ultrasound image showing a linear echogenic structure with central lucency without acoustic shadow effect in common bile duct