Answer - Pancreatic ascariasis with acute pancreatitis

The ultrasound (USG) shows enlarged pancreas with a long, linear, echogenic strip without distal acoustic shadowing occupying the region of the main pancreatic duct [Figure - 3] and double echogenic lines with a central isoechoic strip noted in the duct in the body of pancreas [Figure - 3],[Figure - 4]. These findings are characteristic of ascariasis. ERCP shows a filling defect in the main pancreatic duct [Figure - 5]. Only a small portion of the worm could be removed endoscopically. The patient was operated after failure of endoscopic removal.

Ascariasis is the most widespread helminthiasis in the world. Ascariasis is an important etiological factor in acute pancreatitis in endemic areas. ^[1] A few cases of pancreatitis and obstructive jaundice due to hepatic and pancreatic ascariasis have been reported from areas where it is uncommon. ^[2],[3] USG is the imaging method of choice and demonstrates the presence of Ascaris lumbricoides in the biliary and the pancreatic ducts, as well as signs of pancreatitis, cholecystitis and hepatic abscess. Recurrent pancreatitis due to an impacted calcified Ascaris remnant within the duct of Wirsung has been reported. ^[4]

Adult ascariasis infection gives rise to two kinds of disease: the first is intestinal ascariasis, which is frequently encountered and the second is a condition called ascariasis aberrance, which appears with the migration of the worm to organs outside the intestines. Despite the fact that the adult Ascaris is generally not very active in the intestines, in some cases it may enter orifices linked to the intestines such as the stomach, large intestines, pancreatic canal and bile duct, thereby reaching the thinner biliary canals in the liver. Whereas intestinal ascariasis generally does not cause any serious problems, the settling of the worms outside the intestines is likely to cause serious disease. ^[5] It may give rise to serious conditions such as biliary colic, acute cholecystitis, acute cholangitis, acute pancreatitis and hepatic abscess. ^[6]

In a study carried out in India, where ascariasis is widespread, hepato-pancreatic ascariasis was held responsible for 23% of acute pancreatitis cases. It was reported that acute pancreatitis was slight in 78% of cases and severe in 22% and that it was accompanied by pyogenic cholangitis in 13.6% of cases. Treatment by endoscopic methods was successful in 95% of the cases. ^[1] Endoscopic management of ascariasis is feasible, with very low morbidity and a high rate of success. ^[7] USG is considered an effective and reliable method for the diagnosis of hepatobiliary and pancreatic ascariasis. USG shows pancreatic ascariasis as long, linear, nonshadowing echogenic strips in a dilated pancreatic duct. ^[8]