perforation of the biliary system occurs 
 most frequently in the gallbladder , usually associated with ( and complicating 
 upto 10% cases of ) acute cholecystitis .
perforation of the extrahepatic biliary 
 tree is a rare entity , accounting for less than 10% of intraperitoneal biliary 
 rupture .
bile duct perforation is most commonly described in infants related to congenital 
 biliary system anomalies .
aetiology in the adult is commonly attributable to 
 intramural infection , necrosis of the wall of the bile duct secondary to 
 thrombosis , increased intraductal pressure secondary to obstruction , cirrhosis , 
 and direct erosion by calculi .
overall , 70% of cases are related to calculi 
 . the incidence of biliary tract disease during pregnancy ranges from 0.050.3% . despite these apparent low 
 figures , complications from gallstones
represent the most common general surgical condition 
 requiring surgical intervention , second only to appendicitis .
indications for intervention of gallstones during pregnancy 
 include obstructive jaundice , acute cholecystitis , or pancreatitis failing 
 medical management .
we present the case of a young woman diagnosed with 
 gallstones in late pregnancy , complicated by acute gallstone pancreatitis and 
 subsequently spontaneous common bile duct perforation .
a twenty - year - old primigravida woman was 
 planned for elective caesarean section due to breech presentation .
the patient 
 had a past medical history of -thalassemia trait , but was not 
 normally on regular medication .
her mother had previously undergone a 
 cholecystectomy for gallstones . at 34 weeks gestation , she presented 
 acutely with a two - week history of worsening abdominal pain localised to the 
 epigastric region , associated with vomiting . on examination ,
blood results revealed raised inflammatory markers ( wbc 14.4 [ 4.011.0 ] , 
 neutrophils 11.9 [ 2.07.5 ] , crp 60 
 [ 07.5 ] ) and evidence of pancreatitis ( amylase 1369
iu / l [ 36128 ] ) , mildly 
 raised bilirubin ( 24 mol / l [ 020 ] ) and raised alkaline phosphatase ( 183
an abdominal ultrasound revealed multiple small gallstones and a 
 thickened gallbladder wall , but no evidence of a dilated intra or extrahepatic 
 biliary system .
the patient was treated conservatively , rapidly improved , and liver function tests 
 normalised .
an emergency caesarean 
 section was performed and a term baby delivered , but no obvious cause was found 
 to explain her clinical condition .
the following day her clinical condition worsened , with progressive abdominal pain 
 and a metabolic acidosis .
she required aggressive resuscitation , inotropic , and ventilatory support and was , 
 therefore , admitted to the intensive care unit .
a computed tomography ( ct ) 
 revealed extensive free peritoneal fluid and gas of which the aetiology was not 
 apparent .
the patient underwent a prompt laparotomy and was found to have 
 generalised biliary peritonitis .
the gallbladder was intact but a 2 mm 
 perforation was found on the anterior surface of a dilated common 
 bile duct ( 12 mm ) . on table
cholangiography suggested obstruction of the distal 
 common bile duct caused by a 5 mm gallstone impacted within the distal common 
 bile duct . 

the calculus was removed , and the duct was repaired over a t - tube .
a t - tube cholangiogram was performed 
 after 4 weeks , and the tube was uneventfully removed ( figure 1 ) .
although the pathogenesis of spontaneous biliary perforation is poorly understood , 
 recognised mechanisms include the following : calculous perforation at the site 
 of impaction ; calculous erosion without impaction ; increased canalicular 
 pressure due to obstruction by tumour , stone , or spasm of the sphincter of 
 oddi ; intramural infection ; mural vessel infarction leading to mural necrosis ; 
 or rupture of a biliary tract anomaly such as cyst or diverticulum .
thus , 
 because perforation of the biliary system is a recognised complication of 
 cholelithiasis , the diagnosis should be suspected if a perihepatic abscess or 
 peritonitis is combined with biliary stone disease . as early as 1882 , freeland   reported the first case of extrahepatic biliary system rupture in an adult ( diagnosed at autopsy ) , an entity that was 
 subsequently first described in pregnancy by piotrowski et al .   over a 
 century later . since this time ,
very few cases of spontaneous common bile duct 
 perforation in adults have been reported in the literature , with cases 
 occurring during pregnancy being even more scarce .
the importance of this clinical 
 scenario lies in the potential serious morbidity and not infrequent mortality 
 associated with missed biliary system perforation .
petrozza 
 et al .   described two cases of gallbladder perforation due to cholelithiasis in 
 the early postpartum period .
both cases presented a diagnostic dilemma , and it 
 was concluded that a history of cholelithiasis in a patient with persistent 
 intra - abdominal symptoms in the postpartum period must alert to prompt 
 investigation and early management .
, 
 one patient was found to have suffered gallbladder rupture as a result of 
 cholecystitis , and in the second , a common bile duct perforation was found at 
 laparotomy with no obvious precipitating cause .
.   also drew 
 attention to the similarity of symptoms of gallbladder disease in pregnancy to 
 mild pre - eclampsia , having in common hypertension , epigastric pain , and mildly 
 deranged liver function tests .
these cases highlight the importance of 
 recognising the possibility of delayed diagnosis of cholelithiasis as a result 
 of nonspecific abdominal symptoms during pregnancy and indicate early 
 investigation and treatment in order to reduce serious morbidity .
. 
 block and kelly   reported the optimum time for surgical management of 
 gallstone pancreatitis to be in the second trimester or early postpartum 
 period , in order to minimise maternal / fetal mortality and recurrent 
 pancreatitis .
unfortunately , in those women presenting 
 late in pregnancy ( as in the case described ) , the balance of risk favours 
 watchful waiting until after delivery followed by elective cholecystectomy . 
 certainly , this risks early recurrence of acute pancreatitis , as well as rare but severe 
 consequences such as biliary peritonitis . 
 whether an early endoscopic retrograde cholangiopancreaticography ( ercp ) 
 and sphincterotomy in those cases presenting with gallstone pancreatitis can be 
 an acceptable temporary preventive measure is unclear , but undertaking ercp is 
 not without risk , and the potential risks should be considered carefully in 
 individual cases . in this particular case , 

it is impossible to know whether the eroding calculus had been present during the 
 initial episode of pancreatitis .
magnetic resonance scanning is a commonly used 
 imaging modality in obstetrics , considered to be safe and avoiding the use of 
 ionising radiation .
therefore , magnetic resonance cholangiopancreatography 
 ( mrcp ) would have been a reasonable next investigation during this patient s 
 initial presentation , and if a ductal stone had been revealed , then the indication 
 for ercp may have been clearer .
on the other hand , neonatal and postnatal 
 care of babies born early have progressed significantly , suggesting the 
 possibility of induction of labour perhaps at 3638 weeks 
 gestation in severely symptomatic or high - risk patients .
of course , every case 
 must be considered individually , taking into account maternal and fetal 
 history and health .
 spontaneous perforation of the extrahepatic biliary system is a rare presentation of ductal stones . 
 we report the case of a twenty - year - old woman presenting at term with biliary peritonitis caused by common bile duct ( cbd ) perforation due to an impacted stone in the distal common bile duct . 
 the patient had suffered a single herald episode of acute gallstone pancreatitis during the third trimester . 
 the patient underwent an emergency laparotomy , bile duct exploration , and removal of the ductal stone . 
 the postoperative course was uneventful . 