Internal hernia caused by a congenital peritoneal defect in the vesicouterine space

Abstract

Internal hernias are protrusions of viscera that can cause obstructions such as small bowel obstruction (SBO). Diagnosis can be challenging, as they usually come with an atypical presentation. We report on a case of a woman in her early 40s, with no history of surgery or chronic illnesses, which came with abdominal pain associated with vomiting. CT scan revealed obstructed small bowel. On exploratory laparoscopy, an internal hernia through a peritoneal defect in the vesicouterine space was found, entrapping a limb of the jejunum. The entrapped loop of the small bowel was freed, the ischaemic part was resected, and the defect was closed. Our case presents the second reported case of a congenital vesicouterine defect causing SBO. It is important to consider patients presenting with SBO as a case of congenital peritoneal defect if they had no previous surgeries.

Background

Protrusions of the abdominal viscera by normal or abnormal openings are defined as internal hernias.¹ With an incidence rate of <1%, internal hernias cause 0.6%–5.8% of small bowel obstructions (SBOs).^{1 2} They generally have an atypical clinical presentation, leading to a misdiagnosis and if left uncorrected, this defect can lead to SBO. On physical examination, no physical protrusion can be detected, unlike ventral and inguinal hernias. Therefore, patients can present with abdominal obstructive symptoms but become unremarkable on initial examination.³ Congenital hernia orifices usually result from anomalies of peritoneal attachment and internal rotation. They include normal foramina or recesses as opposed to acquired hernias that are secondary to surgical defects or inflammation and trauma.^{1 4} With only one case reported of a congenital peritoneal defect in the vesicouterine space worldwide, this becomes the second.

Case presentation

A woman with no history of surgery or chronic illnesses in her early 40s came to the ER (Emergency Room) reporting of lower abdominal pain. It started 3 days ago that is associated with vomiting. No constipation was reported by the patient, and there is no previous history of surgical procedures nor any family history of a similar complaint. On physical examination, her blood pressure was 139/91 mm Hg, and her temperature was 38.1°C. Local examination showed a soft lax abdomen with suprapubic tenderness and absent bowel sounds. The patient was resuscitated and then sent for further investigations.

Investigations

On laboratory investigation, an abnormally high white blood count was documented (12.39 10⁹/L), which indicates an active inflammatory process. C reactive protein level was not measured when it should have been. An ultrasound and CT scan with intravenous contrast of the abdomen and pelvis were conducted. The CT scan revealed multiple dilated small bowel loops measuring up to 3.2 cm, with a transition zone at the right lower quadrant. At the right lower quadrant, there is a small bowel loop obstructed proximally and distally (figures 1 and 2) with thickened enhancing wall and surrounding-free fluid, worrisome for closed loop bowel obstruction. The cecum, ascending colon and transverse colon are collapsed. The descending colon and rectum are filled with faecal matter.

Figure 1.

Selected coronal CT scan of the abdomen and pelvis showing a dilated small bowel loop within the right lower abdomen with mild circumferential wall thickening.

Figure 2.

Selected sagittal CT scan of the abdomen and pelvis showing a dilated small bowel loop with circumferential wall thickening and surrounding minimal free fluid worrisome for bowel ischaemia.

Treatment

The patient was immediately taken to the operating room, where a midline laparotomy was performed. A limb of the jejunum was trapped in two peritoneal defects at the vesicouterine pouch (figure 3), one on each side, forming a blind loop of about 10 cm in length that was dusky and dark (figure 4). There were no adhesions found or any further abnormalities.

Figure 3.

Mid line laparotomy shows two peritoneal defects between the uterus and bladder.

Figure 4.

The trapped ischaemic loop of the small intestines.

The jejunal loop was pulled out of the two defects. The ischaemic part was surgically resected with side-to-side anastomosis using a gastrointestinal anastomosis stapler of the two healthy ends. Two drains were placed, followed by abdominal closure in layers with skin closed by staples and covered by dressing. Postoperatively, the patient was placed on intravenous paracetamol, intravenous KCl (Potassium chloride) and a nasogastric tube. The patient was stable the next day, and early ambulation was encouraged.

Outcome and follow-up

The patient was contacted through her provided phone number; however, she was unattainable and her next in kin (her brother) informed us that there were no postoperative complications to note.

Discussion

Internal hernias are believed to be responsible from 0.2% to 5.8% of all incidents of small intestinal occlusion.^5–7 Up to 53% of all incidences of internal hernia are para duodenal hernias, also known as congenital mesocolic hernias. It usually affects men between the ages of 40 and 60 and permanently affects the left side of the body.^{8 9} Other types are pericecal, foramen of Winslow, transmesenteric, transmesocolic, intersigmoid and retroanastomotic, which is the least common.¹⁰

The vesicouterine space is a peritoneal fold that covers the bladder and uterus, constructing a pelvic cavity.¹¹ Hernia in the vesicouterine has only been reported once due to a congenital defect, such herniation caused by a defect in the peritoneum can result in SBOs.³ Clinical symptoms depend on the severity and nature of the hernia, whether it has caused strangulation or incarceration of the small bowel or not. If so, symptoms include periumbilical pain described as colicky in nature, epigastric pain or general abdominal discomfort.³ There are a few reported cases of internal hernias through congenital peritoneal defects.^{3 4} As with our case, previously reported cases had patients reporting of abdominal pain. However, other cases reported the presence of abdominal distention and constipation, which verifies the presence of a bowel obstruction. The first-line diagnostic tool for internal hernias is CT imaging.⁴ In the past, patients suspected of having SBO were routinely given high-attenuation oral contrast material. The administration of it has the benefit of ruling out a high-grade occlusion if it flows distally into the decompressed small intestine. However, the routine administration of high-attenuation oral contrast material has been recently abandoned because patients with SBO typically present with nausea and vomiting, which may lead to the aspiration of contrast. Second, contrast material hardly ever opacifies the digestive tract adjacent to the transition point in a high-grade obstruction. Intravenous contrast CT is generally more desirable as it highlights the presence of ischaemia and inflammation better than any other modality.¹² It remains a challenge to diagnose internal hernias with current imaging techniques; however, the most characteristic findings that will be present to include abnormally located distended bowel loops, crowding of small-bowel loops within a hernia sac and segmental dilatation obstruction.³ Closure of the peritoneal defect is the most appropriate way of treatment in this and many other cases. However, resectioning may be needed depending on the viability of the small bowel.¹³ Our case presents the second reported case of a congenital vesicouterine defect causing SBO. It is important to consider patients presenting with SBO as a case of congenital peritoneal defect if they had no previous surgeries.

Patient’s perspective.

I was having severe abdominal pain with vomiting and had no idea of the cause. When I went to the ER, I was in a lot of pain, and after a few blood tests and a CT scan, they informed me that I needed urgent surgery. They said I had bowel obstruction, which what was causing my symptoms. After the surgery, I felt a lot better, and I no longer felt the pain I once had. I did not think it was necessary for me to follow-up since I was not experiencing any complications after the surgery and my symptoms had stopped. When I was called to be part of this study, I was surprised to find out that the reason for my pain was a congenital problem.

Learning points.

• Small bowel obstruction caused by an entrapped internal hernia caused by a congenital peritoneal abnormality is an exceptionally rare event.

• Because clinical symptoms are frequently non-specific, a high level of suspicion and vigilance is essential. It should be considered, particularly in patients with no prior surgical history.

• CT scans detail the anatomy and provide crucial information. In an emergency surgical intervention, open defect repair without mesh is safe.

Ethics statements

Patient consent for publication

Consent obtained from next of kin.