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Paper text:
situs viscerum inversus is a rare condition with a genetic predisposition , with a frequency of 1:5,000 to 1:10,000 live births , in which the organs are transposed , totally or partially , to the opposite side of the body . in total situs inversus
there is a complete transposition of all viscera , dextroposition of the heart , and the liver is palpable in the left upper quadrant .
endoscopic sphincterotomy and stone extraction are standard procedures for the removal of bile duct stones .
the instrumentation , the side view endoscope , is built for the right position of the liver with the papilla at the medial side of the duodenum .
we report the case of a 69-year - old female , cholecystectomized , with choledocholithiasis and total situs inversus , in whom an ercp was performed with sphincterotomy and bile duct stone extraction .
a 69-year - old white female with known total situs viscerum inversus , with previous cholecystectomy , right radical nephrectomy , polycystic disease of the left kidney , hemodialyzed , presented to our emergency department with colicky pain located to the abdominal left upper quadrant with irradiation toward the subscapular region and upward to the left shoulder .
the pain had started 24 h earlier and was associated with nausea , vomiting , fever ( 38.5c ) and jaundice .
physical examination revealed pronounced tenderness on the left hypochondrium , polycystic kidney and decreased bowel sounds .
the edge of the liver was soft and palpable two fingers below the left costal margin on deep inspiration .
laboratory studies showed : white cell count 15,500/ml ( n. 4,00010,000 ) ; total bilirubin 5.88 mg / dl with direct fraction of 5.53 mg / dl ; ast 119 u / l ; alt 130 u / l ; amylase 357 u / dl ; lipase 1,535 u / dl ; alkaline phosphatase 845 u / dl ; gamma - gt 685 u / dl ; creatinine 2.5 mg / dl ; bun 78 mg / dl .
abdominal ultrasound ( us ) confirmed the situs viscerum inversus and showed a dilatation of the intra- and extrahepatic bile duct with a stone in the common duct .
the patient was admitted to the hospital and antibiotics therapy ( piperacillin 2 g  3 i.v . ) and infusional therapy was started .
a magnetic resonance cholangiopancreatography demonstrated a 1.3 cm peripapillary stone with the common bile duct dilated to 1.5 cm ( fig . 1 ) and total situs viscerum inversus .
four days after admission , the patient underwent a therapeutic ercp with sphincterotomy and stone extraction .
after premedication with pharyngeal xilocaine 10% and conscious sedation with diazepam 5 mg , duodenoscopy was performed with a lateral - view endoscope ( olympus tjf-30 ) .
the patient was in the usual prone position with the endoscopist at the right side of the table .
in the stomach the endoscope was turned 180 degrees to the right and , under fluoroscopic control , the second portion of the duodenum was reached ( fig .
2 ) : another 180 degrees tortion towards the right was necessary and pushing against the duodenal wall the papilla was maintained in the correct position retrieving the instrument in the short position , diminishing the torsion of the instrument .
the ercp was carried out in the usual way with a long - nose cannulotome ( boston scientific ) .
the cholangiography confirmed the dilatation of the common bile duct up to 16 mm with an impacted stone of 15 mm ( fig .
3 ) . after a standard sphincterotomy the stone was removed with a dormia basket .
the postoperative course was uneventfull , pancreatic enzymes remained within the normal range and the patient was discharged after two days .
this is preferred because it allows a better delineation of the biliary and pancreatic duct anatomy .
biliary cannulation has a success rate of almost 100% with the patients in the prone position .
many reports showed that the supine position does not affect the feasibility of ercp when the operator turns the instrument clockwise 180 degrees .
ercp can be technically challenging because of anatomic variants , when operative alteration are carried out on the upper digestive system ( such as billroth i , billroth ii gastric resection , roux - en - y enteroanastomosis etc . ) , and in case of pathological changes .
endoscopic access to the papilla is 92% in billroth ii and 33% in roux - en - y reconstructions .
the exact etiology remains obscure , but attempts have been made to explain it on the basis of a complex gene with variable expression .
reported a case of ercp performed in situs viscerum inversus keeping the patient in the prone position and the endoscopist at the left side .
however , extrarotation of the instrument , this time counterclockwise , was necessary as the instrument is built with the side view .
we succeeded to pass the stomach and to reach the duodenum with only a 180 degrees turn and the correct position was maintained pushing the second portion of the duodenum as it happens reaching the papilla in the billroth ii patient .
the x - ray showed the position of the endoscope quite similar to that obtained in the billroth ii patient , naturally on the other side ( fig .
3 ) . in conclusion , this report shows that in expert hands it is possible to perform ercp in every anatomical condition , also in patients with situs viscerum inversus .
a 69-year - old cholecystectomized female with known total situs viscerum inversus presented recurrent colicky pain in the left upper abdominal quadrant and jaundice . 
 laboratory parameters showed increased neutrophils and coniugated bilirubin of 5.53 mg / dl . 
 us and mrcp confirmed total situs viscerum inversus and a dilatation of the intra- and extrahepatic ducts with a peripapillary 13 mm stone . 
 ercp , sphincterotomy and successful common bile duct stone extraction were performed in the conventional way . 
 ercp was carried out successfully despite situs inversus maintaining the patient in the prone position with the endoscopist on the right side of the table . 
 some authors have reported similar cases in whom ercp was performed in other positions , while this report shows that an experienced endoscopist can achieve the same results in the conventional way as it is possible when anatomical changes , billroth ii or roux - en - y , or different positions of the patient , supine or on the left side , are present .