Adult Distal Duodenal Obstruction: A Diagnostic and Therapeutic Challenge.

Distal duodenal obstruction (DDO) can be succinctly defined as features of gastric outlet obstruction with bilious vomiting and radiological or endoscopic evidence of post-bulbar obstruction. Obstructions of the third (D3) and fourth (D4) parts of the duodenum are rare and present significant diagnostic and surgical challenges, particularly when the cause is malignant. In the following three case reports, we discuss three distinct aetiologies of this rare syndrome and highlight important considerations surrounding the early investigation and management of these individuals. The first patient is a 60-year-old lady with primary duodenal adenocarcinoma resulting in malignant stricture at D4. She underwent segmental resection of the D4 tumour with a duodeno-jejunal anastomosis. The second patient is a 17-year-old boy with superior mesenteric artery (SMA) syndrome, who was treated conservatively. The last patient is a 71-year-old lady with a caecal carcinoma invading the retroperitoneal structures and D3. The patient underwent a palliative laparoscopic gastro-jejunostomy. Although infrequently encountered in clinical practice, the individual burden of a missed or late diagnosis of DDO, malignant or otherwise, can be disastrous. This case series illustrates the varied presentation of DDO and discusses current principles of investigation and management.