Type B choledochocele vs duodenal duplication cyst: a diagnostic dilemma and its management: a case report

Abstract

Introduction: Duplication cyst of the alimentary tract is a rare congenital anomaly. Duodenal duplication cyst accounts for less than 5% overall. These entities rarely present in adults. They are often mistaken as choledochoceles. Management is most often complete excision, but it is individualized to the particular case.

Case presentation: A 22-year-old woman was admitted to our hospital with a history of intermittent colicky right hypochondrial pain not relieved by any medications for the past 3 months. Initially, she was given proton pump inhibitors, but her pain was not relieved. Further evaluation was done, and preoperative imaging showed a cyst in the second part of the duodenum. Magnetic resonance imaging revealed it as a choledochocele, but duodenal duplication cyst was kept in the differential diagnosis. Further ultrasound identified it to be a duplication cyst. After failed endotreatment, the patient was successfully managed with partial excision and marsupialization.

Conclusion: Duodenal duplication cyst is uncommon and rarely diagnosed in adults. Duplications in the duodenum should always be a part of the differential diagnosis, especially in cystic lesions. Ultrasonogram of the cyst might lead to the proper diagnosis. Surgery is the treatment of choice if endotherapy is not successful.

Keywords: Ampulla; Case report; Choledochocele; Duplication cyst; Gut signature; Marsupialization.

Fig. 1

Upper GI endoscopy showing swelling (arrow) in the medial wall of the second part of duodenum

Fig. 2

CECT abdomen with oral contrast shows well defined hypodense lesion (arrow) in the D2 medial wall oral contrast pushed to periphery without communication

Fig. 3

MRI abdomen showing dilatation of the intramural part of distal CBD 2.4 x 2.3cm cyst (arrow) noted ampullary region suggestive of Type 3 choledochal cyst

Fig. 4

Ultra sound showing typical gut signature of the cyst wall (arrow)

Fig. 5

Intra operative image showing 5 x 3cm cyst (arrow) noted in medial wall of D2

Fig. 6

Intraoperative image showing two small tubes in the ampulla. One entering into cyst cavity (Arrow above). Other one entering CBD (Arrow below)

Fig. 7

Intraoperative image showing partial excision (arrow) of the cyst

Fig. 8

Histopathological Section showing cyst wall lined by duodenal mucosal epithelium with focal areas of ulceration and composed of tall columnar cells with goblet cells on either side of a common (shared) muscular layer. Submucosa shows lymphoid aggregates with brunner glands. The common muscular layer shows congested vessels

Fig. 9

a shows type A choledochocele, b shows type B choledochocele and c shows Duodenal duplication cyst. See that B and C communicating to the ampulla. C covered with muscle coat that differentiate this from the Type B choledochocele (copy rights obtained from Elsevier-reference 11)