Uncommon Cases of Small Bowel Obstruction - Cases Series and Literature Review

Small Bowel Obstruction (SBO) is a clinical condition characterized by the interruption of normal intestinal flow. The most common causes include intraperitoneal adhesions with approximately 60-70% of cases. Other causes include neoplasm, hernias, obstructive foreign bodies or gallstones, inflammatory disease or iatrogenic causes. Some symptoms are abdominal pain, distention, vomiting, constipation progressing to obstipation some signs of sepsis. Principal diagnostic tests include leukocytosis, elevated lactic acid, metabolic acidosis and some characterized findings in abdominal CT or x-ray. 

Internal abdominal hernias are secondary to the protrusion of an abdominal organ through a mesenteric or peritoneal defect, congenital or acquired. They occur with an incidence of less than 1%, but constitute 5.8% of all SBO and, due to their late diagnosis, they usually have a mortality rate exceeding 50%. The most common internal hernias are paraduodenal, which account for 50% to 55% of cases; other less common hernias include hernias through the foramen of Winslow (6% to 10%), transmesenteric (8% to 10%), pericecal (10% to 15%), intersigmoid (4% to 8%), paravesical, supravesical and pelvic (<4%). In paravesical hernias, the defect is located between the median and medial umbilical ligaments. There are four subtypes based on the course of the herniated organs: anterior, posterior, right, or left lateral.

The most frequent clinical manifestation is bowel obstruction. The radiological findings of the internal paravesical hernias include a cluster of bowel loops and mesenteric fat adjacent to the bladder with proximal dilatation, deformity of the bladder walls adjacent to the hernia and congestive mesenteric vessels. According to our case, a “closed loop” adjacent to the bladder also could be found. The second case is about a transvaginal intestinal evisceration causing an incarceration of small bowel and intestinal obstruction. The dehiscence occurs in less than 1% of hysterectomies and of these 35-60% result in evisceration. SBO is a frequent surgical event but some etiologies are rare for that reason if the patient does not present typical signs or symptoms we have to think of the rare causes and some radiology studies such as abdominal CT are necessary.