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females are more commonly affected ( ratio 3:1 ) , typically presenting in the 2nd or 3rd decade of life . despite an absent gallbladder , half of patients present with symptoms similar to biliary colic , which is poorly understood . here
, we report a case of a 21-year - old woman who presented with recurrent biliary colic and was diagnosed to have gallbladder agenesis on magnetic resonance cholangiopancreatography ( mrcp ) .
she was in her usual state of health until 6 weeks prior when she developed abdominal pain .
the pain was located in her right upper quadrant , dull , aching in quality , sudden in onset , colicky in nature , and radiated to her right scapula .
the episodes of pain would last for 4590 min following each meal . as a consequence of the post - prandial pain , she developed sitophobia and lost 12 pounds over a 6-week period .
her social history was notable for lack of tobacco , alcohol or illicit drug use .
with respect to her family history , both her parents had had cholecystectomies ; her father at the age of 45 due to gallstone disease and her mother at the age of 39 ( noted to have cholesterolosis ) .
family history was also significant for hemochromatosis in her father ; her mother had not been tested .
the patient presented to the emergency department 4 weeks after symptom onset and given concerns for the biliary nature of her pain , she was evaluated by the surgical service .
she had an ultrasound of her abdomen which showed prominence of her common bile duct ( 7 mm ) without intrahepatic biliary dilatation , and nonvisualization of her gallbladder .
she subsequently underwent a hida scan , which was read as concerning for possible acute cholecystitis given the lack of gallbladder filling .
she was discharged after symptomatic management with plans to be evaluated by gastrointestinal surgery for possible laparoscopic cholecystectomy in 46 weeks . in the interim
, she had recurrence of her symptoms and presented again to the emergency department . at this time
, her exam revealed a nontoxic appearance with normal vital signs and mild tenderness to palpation in her right upper and bilateral lower quadrants without rebound or guarding .
her laboratory testing was notable for an unremarkable basic metabolic panel , cbc and liver enzymes .
status post cholecystectomy. given nonvisualization of the gallbladder on ultrasound as well as ct scan , an mrcp was ordered which revealed a 4-mm cystic lesion seen adjacent to the proximal common hepatic duct with apparent communication via a diminutive duct with the right hepatic duct , consistent with gallbladder agenesis / hypoplasia ( fig .
gallbladder agenesis is a rare entity with an estimated incidence of 1065 per 100,000 [ 1 , 2 ] .
the incidence is noted to be higher ( up to 90 per 100,000 ) in studies based on autopsy reports .
the first reports of cases of gallbladder agenesis date back to 1701 and 1702 by lemery and bergman [ 1 , 2 , 4 ] .
the pathogenesis is related to embryonic development due to failure of the gallbladder and cystic duct to bud off from the common bile duct during the fifth week of gestation .
table 1 summarizes a list of cases reported on gallbladder agenesis including the demographics of patients affected , their initial clinical presentation , mode of diagnosis and their outcomes .
females are more commonly affected ( in a 3:1 ratio ) and typically present in the 2nd or 3rd decade of life .
for unclear reasons , despite the absence of a gallbladder , up to 50% of patients present with symptoms similar to biliary colic . some postulate that an associated sphincter of oddi dysfunction may be the cause of biliary colic in these patients .
in other cases , associated development of common bile duct stones may be the cause .
the second group presents with symptoms of biliary colic ( 54% ) , dyspepsia ( 34% ) and/or jaundice ( 27% ) , and the third presents in childhood with other associated severe fetal anomalies [ 2 , 4 ] .
the exact prevalence of each of the three groups is variable based on published reports .
it is thought that approximately 70% of cases are usually isolated anomalies , although some cases appear to be familial and are associated with more severe anomalies [ 5 , 8 , 9 ] . in an interesting series of 34 cases ( 29 children and 5 adults ) of congenital gallbladder agenesis ,
the most common anomalies associated were involving the genitourinary tract followed by gastrointestinal and cardiovascular malformations .
historically , all cases were identified intraoperatively . in a review of 9 cases by cho et al .
however , now with the increased frequency of advanced imaging , cases are being diagnosed more often and , more importantly , before any surgical intervention . however , given that patients with gallbladder agenesis tend to present symptoms suggestive of biliary colic , a number of them are still diagnosed intraoperatively . due to a lack of awareness of the diagnosis , this entity remains a diagnostic challenge [ 2 , 12 ] . in those cases which are diagnosed intraoperatively ,
patients often are exposed to complications from prolonged exploration , and it is suggested to abort the procedure rather than complete further exploration if a gallbladder is not found on laparoscopy since open exploration for possible ectopic gallbladder increases the risk of complications .
a follow - up with more advanced imaging techniques should be the next option to truly identify gallbladder agenesis as the sole abnormality to guide management further .
it is therefore important to consider the presence of this unusual entity when the nonvisualization of the gallbladder is suggested on ultrasound .
however , as is known , ultrasound is highly dependent not only on the operator but also on other factors such as body habitus or presence of bowel gas obscuring visualization .
cases of gallbladder agenesis have been reported as  contracted / fibrotic gallbladder on ultrasound .
hida scans , which are also usually performed in patients with cholecystitis , in this case are unhelpful since nonvisualization of the gallbladder remains typical of cystic duct obstruction , as well as of agenesis [ 13 , 16 , 17 , 18 ] .
it is also helpful in demonstrating an ectopic gallbladder along with other possible anomalies of the biliary tract system [ 8 , 19 ] . in terms of treatment
interestingly , one author notes that 98% of patients had resolution of symptoms after exploratory , nontherapeutic surgery .
it is unclear how these patients would have had symptom resolution in the absence of exploration .
this was also noted to be the case in 2 cases reported by waisberg et al .   and some of the other reports ( see table 1 ) .
in this case , the patient was started on hyoscyamine extended release tablets twice daily , which did help alleviate her symptoms and has prevented any recurrence of symptoms or hospitalization during a 5-month follow - up . she was also noted to be heterozygous for c282y mutation for hereditary hemochromatosis . whether the gene for gallbladder development is associated with hemochromatosis is not known , and we did not come across studies associating it with gallbladder agenesis .
more cases of gallbladder agenesis are being diagnosed incidentally and outside of the operating room .
clinicians should have a strong index of suspicion if nonvisualization is suggested by an ultrasound .
a positive hida scan can be seen in the presence of gallbladder agenesis in the absence of cholecystitis .
it is also helpful in demonstrating an ectopic gallbladder along with other possible anomalies of the biliary tract system .
gallbladder agenesis is a rare entity with an estimated incidence of 1065 per 100,000 . 
 females are more commonly affected ( ratio 3:1 ) , typically presenting in the 2nd or 3rd decade of life . despite an absent gallbladder , half of patients present with symptoms similar to biliary colic , which is poorly understood . 
 clinicians should have a strong index of suspicion if nonvisualization is suggested by an ultrasound . 
 hida scans are typically not helpful since nonvisualization of the gallbladder remains typical of cystic duct obstruction as well as of agenesis . while there are no specific guidelines for management of gallbladder agenesis , conservative management with smooth muscle relaxants is preferred . 
 sphincterotomy also has been reported in severe cases . here , 
 we report a case of a 21-year - old woman who presented with recurrent biliary colic and was diagnosed to have gallbladder agenesis on magnetic resonance cholangiopancreatography . 
 a comparison with other cases and a review of the literature are presented .