fascioliasis , as a zoonotic disease , mostly affects sheep , goats and cattle and is caused by a 24 cm flat trematode of the liver named fasciola hepatica . the number of reports of humans infected with f. hepatica has significantly increased since 1980 , and several geographic areas have been described as endemic regions for the disease in humans , with different prevalence and incidence rates [ 1 , 2 , 3 , 4 ] . in endemic regions , very young children and women are most likely to be infected , and a high incidence of co - infection with other parasites , especially echinococcosis , is found . in humans , the larvae excyst in the stomach , penetrate the duodenal wall , escape into the peritoneal cavity and then pass through the liver capsule to enter the biliary tree . serologic tests and imaging studies of the hepatobiliary tract are of great importance in diagnosis [ 6 , 7 , 8 , 9 ] . here , we report a 64-year - old woman with epigastric and upper quadrant abdominal pain for the last 6 months , with imaging suggesting liver abscess and normal biliary ducts . finally , endoscopic ultrasonography ( eus ) revealed f. hepatica , which was then extracted with endoscopic retrograde cholangiopancreatography ( ercp ) . a 64-year - old female with epigastric and right upper quadrant pain was referred to taleghani hospital in tehran , iran . there had been 34 episodes of pain on most days , lasting about 1 h and then decreasing gradually for at least 6 month before presentation . she also stated weight loss of about 3 kg ( from 66 to 63 kg ) within 6 months without fever , icterus or any change in bowel habit . in her past medical history her previous laboratory evaluation revealed an increased erythrocyte sedimentation rate ( 64 mm / h ) , while total bilirubin was 3.2 mg / dl ( normal < 2 mg / dl ) , aspartate aminotransferase 31 iu / l ) . complete blood count showed hemoglobin 12.1 g / dl , platelets 190,000/mm ( normal 100,000450,000/mm ) and white blood cells 4,030/mm ( normal 4,00010,000/mm ) with 12% eosinophils ( 484/mm ) on peripheral smear . the results of stool examinations at three different times for detecting ova and parasites as well as occult blood were normal . after admission , ultrasonography and abdominopelvic computed tomography ( ct ) scan showed normal intrahepatic bile ducts , but an ill - defined large heterogeneous mass lesion which contained multiple hypodense portions in the right and caudate lobes of the liver was noted ( fig . after that , the patient underwent evaluation to rule out possible malignant and non - malignant etiologies as follows : endoscopy and colonoscopy were performed to rule out probable sources of liver metastasis , which were both unremarkable . the patient also underwent ct - guided core needle biopsy for pathologic and microbiological evaluation , which showed predominant eosinophil infiltration of liver sections with microabscess ( eosinophilic abscess ) formation without neoplastic or granulomatous process . microbiological cultures of aspiration fluid of the liver mass showed no growth after 72 h. empirically , initial treatment with intravenous ceftriaxone and metronidazole was initiated , followed by oral ciprofloxacin and metronidazole . following antibiotic therapy , the patient 's symptoms alleviated gradually , and erythrocyte sedimentation rate decreased to 10 mm / h within 3 weeks . the patient was discharged from hospital and on follow - up visits mentioned improvement in her general condition . ultrasonography performed 2 months after discharge showed resolution of the liver mass with normal intra- and extrahepatic biliary ducts , but second follow - up ultrasonography revealed a small ( 8  10 mm ) cystic lesion in the right lobe of the liver with dilation of the common bile duct ( cbd ) ( 9 mm ) that was confirmed by magnetic resonance imaging ( fig . 2 ) . magnetic resonance cholangiopancreatography showed a slightly dilated cbd ( 9.5 mm ) and normal intrahepatic bile ducts , with irregularity of the wall of the distal third of the cbd with suspicious filling defect ( fig . 3 ) . finally , eus with a linear echoendoscope showed a 10 mm cbd with long , linear , hyperechogenic structures , moving freely in the lower third of the cbd , in favor of f. hepatica ( fig . , ercp was performed , and after sphincterotomy , an extraction balloon was passed and removed a live fasciola ( fig . 5 ) . fascioliasis is an emerging disease in humans , while sheep and cattle are the most important definitive hosts of f. hepatica ; goats , buffalo , horses , camels , hogs , deer , and rabbits can also be infected . its eggs are oval and yellow - brown , with a dimension of approximately 130150  6090 m . the life span of adult f. hepatica flukes within humans is not known but is estimated to be 913 years . it occurs mainly in sheep - rearing areas of temperate climates , particularly in certain parts of central and south america , europe , china , africa and the middle east . the number of adult flukes that reach the biliary tree and fully develop to sexual maturity is usually small . during wet years , the degree of animal infection and the incidence of human infection rise because of an increased number of snails and longer survival of encysted cercariae . human hepatobiliary infection with f. hepatica has two phases : acute ( hepatic ) and chronic ( biliary ) . the early acute phase , which usually begins within 612 weeks of metacercariae ingestion , is often associated with fever , right upper quadrant pain and hepatomegaly . general non - specific symptoms and signs including anorexia , nausea , vomiting , myalgia , cough and urticaria as well as peripheral eosinophilia are common in this phase [ 10 , 13 ] . the biliary phase is usually asymptomatic , but may present with intermittent right upper quadrant pain with or without cholangitis or cholestasis . occasionally , the adult flukes can obstruct the cbd and thus induce chronic infection leading to biliary colic , cholangitis , cholelithiasis , obstructive jaundice and even secondary pancreatitis [ 11 , 14 , 15 , 16 , 17 ] . serologic tests and imaging studies of the hepatobiliary tract are of great importance in diagnosis [ 6 , 7 , 8 , 9 ] . due to diverse presentations of fascioliasis , there is often a delay in diagnosis , particularly in patients in the hepatic phase . the diagnosis can be established by serology or by identifying eggs in duodenal aspirates , bile specimens or stool . alternative approaches to diagnosis include imaging studies , particularly ct scan of the liver which may show characteristic hypodense nodules or tortuous tracks resulting from migration of the parasite through the liver [ 6 , 7 ] . magnetic resonance cholangiography , eus and ercp are useful in identifying the flukes in the bile ducts and gallbladder in the biliary phase . we report this case to emphasize that there might be several ambiguous aspects in diagnostic evaluations of f. hepatica , and fascioliasis should be kept in mind in patients with preceding vague gastrointestinal symptoms , especially in endemic areas . our case did not have significant peripheral eosinophilia or typical clinical presentation , while eosinophilia is very common in the acute phase , and there were no biliary obstruction symptoms . besides , in comparison to other cases in the literature , the initial imagings did not show any abnormality in the biliary ducts , despite the patient having eosinophilic liver abscess [ 14 , 15 , 16 , 17 , 19 , 20 , 21 ] . stool examination may be negative for fascioliasis , and there is no obvious suggestive diagnostic clue , so this highlights the fact that f. hepatica should be considered in the differential diagnosis of ambiguous hepatobiliary symptoms , especially in endemic areas .
fascioliasis is an endemic zoonotic disease in iran . 
 it occurs mainly in sheep - rearing areas of temperate climates , but sporadic cases have been reported from many other parts of the world . 
 the usual definitive host is the sheep . 
 humans are accidental hosts in the life cycle of fasciola . 
 typical symptoms may be associated with fascioliasis , but in some cases diagnosis and treatment may be preceded by a long period of abdominal pain and vague gastrointestinal symptoms . 
 we report a case with epigastric and upper quadrant abdominal pain for the last 6 months , with imaging suggesting liver abscess and normal biliary ducts . 
 the patient had no eosinophilia with negative stool examinations , so she was initially treated with antibiotics for liver abscess . 
 her clinical condition as well as follow - up imagings showed appropriate response after antibiotic therapy . 
 finally , endoscopic ultrasonography revealed fasciola hepatica , which was then extracted with endoscopic retrograde cholangiopancreatography .