DUPLICATED GALLBLADDER

 

Prevalence: 2.5:10,000 discovered at autopsy. Over 200 cases reported in the literature.

Definition: Gallbladder duplication occurs when two separate gall bladder cavities develop, each with separate cystic ducts.

Etiology: Embryologic abnormality of biliary tract development with a persistence and development of a normal vestigial out pouching of the biliary tree.

Pathogenesis: Unknown.

Associated anomalies: Increased incidence of forgut malformations and aberrant vasculature.

 

 

 

 

CLASSIFICATION

 

Boyden"s classic description defines gallbladder duplication as an embryologic abnormality in biliary tract development resulting in two separate gallbladder cavities, each with a cystic duct. Boyden examined over 19,000 human cadavers finding only 5 cases of gallbladder duplication. Interestingly, duplication was found in 1 of 8 cats, 1 of 28 calves and 1 of 85 lambs.

A case of triple gallbladder has been reported as well. Duplication is more common than bilobation

 

 

ASSOCIATED ANOMALIES

 

Several anomalies have been associated with gallbladder duplication including forgut malformations and aberrant hepatic and mesenteric vessels2,3. Sono­gra­phic distinction between types of duplications (i.e. anatomy of cystic ducts) and detection of aberrant vessels has not been reported in the literature.

 

 

DIFFERENTIAL DIAGNOSIS

 

 

PROGNOSIS

 

 

The prognosis for gallbladder duplication is good. Although several authors report increased risk of acute and chronic cholecystitis, cholesterolosis, papilloma, carcinoma, biliary cirrhosis and torsion, other reports did not confirm this increased risk2-8.

Therefore, when gallbladder duplication is discovered in utero, the patient can be reassured as to the benignancy of the finding.

 

REFERENCES

 

1. Boyden E.A. The accessory gallbladder. Am J Anat 1926;38:177-231.

2. Udelsman R. Congenital duplication of gallbladder associated with an anomalous right hepatic artery. Am J Surg 1985;149:812-815.

3. Nichols DM, Superior mesentric vein rotation: a CT sign of mid-gut malrotation. AJR 1983;141:707-8.

4. Ryrberg C.H. Gallbladder duplication. Acta Chir Scand 1960;119:36-44.

5. Granot E. Duplication of gallbladder associated with childhood obstructive biliary disease and biliary cirrhosis. Gastroenterology 1983;85:946-950.

6. McDonald K, Sonographic and Scintigraphic evaluation of gallbladder duplication. Clin Nucl Med 1986;11(10); 692-693.