Prevalence of biliary ascariasis and its relation to biliary lithiasis.

Hepatobiliary ultrasound was carried out on 2224 consecutive patients at the Center for Nuclear Medicine and Ultrasound and at one private diagnostic center in Mymensingh for ultrasound examination of different systems. The purpose of this study was to investigate the prevalence of biliary ascariasis and its association with other biliary diseases, specially biliary lithiasis. Data regarding the presence of stone, worm or other diseases were recorded accordingly in this prospective study. There were 952 male and 1272 female patients with an age range of 5-90 years. Biliary diseases were detected in 305 patients (13.71%), of whom 97 were male (10.19%) and 208 were female (16.35%). The most common biliary disease in both sexes was cholelithiasis (11.87%), which was found in 84 male patients (8.82%) and in 180 female patients (14.15%). Other diseases found were choledocholithiasis in 14 patients (3 males, 11 females), gall bladder mass in 9 patients (3 males, 6 females), common bile duct mass in 7 patients (4 male, 3 female) and biliary ascariasis in 10 patients (3 male, 7 female). Overall prevalence of biliary ascariasis was 0.45% (0.31% in male patients and 0.55% in female patients), and age range of patients with the condition was 6-50 years. No case of biliary ascariasis was associated with cholelithiasis or choledocholithiasis. Acute cholecystitis was associated with 8 cases (80%) of biliary ascariasis. Common sonographic findings in patients with biliary ascariasis were a single long, linear or curved echogenic structure within the bile duct, without acoustic shadowing. Other findings were gall bladder distention with sludge inside, an edematous wall and mildly dilated biliary tree. Prevalence of biliary ascariasis in the study was 0.45%, with incidence being higher in female subjects (0.55%). No correlation was found between biliary ascariasis and biliary lithiasis. Most of the cases of biliary ascariasis were associated with acute cholecystitis. We concluded that a careful search for biliary ascariasis should be considered for patients with acute acalculus cholecystitis, especially in areas in which ascariasis is endemic, such as Bangladesh.