Determining the etiology of small bowel obstruction in patients without intraabdominal operative history: a retrospective study

Abstract

Purpose: Most of the causes of small bowel obstruction (SBO) in patients without a history of abdominal surgery are unclear at initial assessment. This study was conducted to identify the etiology and clinical characteristics of SBO in virgin abdomens and discuss the proper management.

Methods: A retrospective review involving operative cases of SBO from a single institute, which had no history of abdominal surgery, was conducted between January 2010 and December 2020. Clinical information, including radiological, operative, and pathologic findings, was investigated to determine the etiology of SBO.

Results: A total of 55 patients were included in this study, with a median age of 57 years and male sex (63.6%) constituting the majority. The most frequently reported symptoms were abdominal pain and nausea or vomiting. Neoplasm as an underlying cause accounted for 34.5% of the cases, of which 25.5% were malignant cases. In patients aged ≥60 years (n=23), small bowel neoplasms were the underlying cause in 12 (52.2%), of whom 9 (39.1%) were malignant cases. Adhesions and Crohn disease were more frequent in patients aged <60 years. Coherence between preoperative computed tomography scans and intraoperative findings was found in 63.6% of the cases.

Conclusion: There were various causes of surgical cases of SBO in virgin abdomens. In older patients, hidden malignancy should be considered as a possible cause of SBO in a virgin abdomen. Patients with symptoms of recurrent bowel obstruction who have no history of prior abdominal surgery require thorough medical history and close follow-up.

Keywords: Abdominal pain; Etiology; Ileus; Intestinal obstruction; Neoplasms.

Fig. 1.

The operative findings of a 21 years-old male patient with small bowel obstruction diagnosed with Crohn disease. (A) Creeping fat sign and (B) mesenteric thickening due to fibrofatty proliferation of the mesenteric tissue adjacent to chronic inflammation of bowel loops (white arrows). (C, D) The abdomen computed tomography scan shows targetoid small bowel (blue arrows) which is intussusception.

Fig. 2.

The operative findings of a 48-year-old male patient who had small bowel obstruction after abdominal blunt trauma history. (A) The intraoperative finding. The fibrotic change in mesentery was caused by trauma (white arrows) and proximal bowel distension (asterisk). The distal part of the injured bowel was collapsed. (B) Gross finding of the specimen after the small bowel resection. Bowel wall thickening (white arrows) and segmental stenosis (asterisk) were associated with ischemic changes that were caused by a tear of the mesenteric vessel. (C, D) The abdomen computed tomography scan shows small bowel ileus and abrupt segmental stricture in small bowel adjacent to terminal ileum (blue arrows).

Fig. 3.

The abdomen CT findings of an 80-year-old male patient who had recurrent SBO without any surgical history. Initial CT scan shows segmental stricture of small bowel and mild distension of proximal small intestine without mass-like lesions (blue arrows) in both axial veiw (A) and coronal veiw (B). This patient was finally diagnosed with small bowel adenocarcinoma postoperatively.