Adult Distal Duodenal Obstruction: A Diagnostic and Therapeutic Challenge

Abstract

Background: Varied pathologies in the distal duodenum (both intrinsic and extrinsic) can give rise to the features of duodenal obstruction. Distal duodenal obstruction is defined as featues of gastric outlet obstruction with bilious vomiting and radiological evidence of post-bulbar obstruction. Obstruction of the third (D3) and fourth (D4) part of the duodenum are rare and present significant diagnostic and surgical challenges. Given the vague symptomatology in early stages and the fact that D3/D4 lesions are often missed by conventional endoscopy, these patients present late and often are misdiagnosed. Methods: We present a case series of three patients presenting with distal duodenal obstruction, but with very differing aetiology and management. The data was analysed from a prospectively managed database as well as from the electronic patient records and we discuss the investigative workup and attempts at diagnosis along with the treatment of these patients. Results: Case1: 60-year old lady admitted with vomiting and weight loss. Previously been investigated for 6 months with features of weight loss, early satiety and vomiting. CT scan showed an obstruction at D4. Enteroscopy revealed a malignant stricture at D4 with complete obstruction which was localised on a PET scan. The patient underwent a resection of the D4 tumour with duodeno-jejunal anastomosis. The histology revealed duodenal adenocarcinoma which was completely resected (R0). She remains well at 18 months follow-up. Case 2: 17-year old boy who presented with vomiting and weight loss. CT showed a grossly dilated stomach with cut off at D3. MRI revealed a superior mesenteric artery (SMA) syndrome. He was treated conservatively with initial parenteral nutrition and gradual increase in diet over 4weeks. He picked up weight and is currently eating and drinking normally at 14 months follow-up. Case 3: 71-year-old lady who presented with vomiting and early satiety.CTscan revealed an ascending colon malignancy which was invading the retroperitoneal structures and D3. Given the location wasn't suitable for duodenal stenting, the patient underwent a palliative laparoscopic gastro-jejunostomy to enable her to eat. She passed away in a hospice after 4 months of surgery. Conclusions: Distal duodenal obstruction is a clinical entity with a wide variety of differentials. Initial clinical symptoms can be quite vague, in the form of early satiety, intermittent vomiting, anaemia and weight loss and should prompt us to investigate with increasing use of enteroscopy and cross-sectional imaging. In these patients, it is important to remember that given its location, they are not usually amenable to stenting and surgery is often required, but is obviously dependant on aetiology of the obstruction.