Herein, we presented an extremely rare case of LPDH associated with complete common mesentery, which was found incidentally
To the best of our knowledge, there are no previous reports of these association. Both being rare congenital anomalies.
What makes our observation very rare, apart from this association, is that the diagnosis was made in adulthood, which underlines the importance of considering intestinal rotation anomalies in adults.
In order to better understand the clinical manifestations of all these anomalies, it is important to review the embryology of the normal sequence of events relating to the midgut position (Fig. 2a).
In the physiological situation, the midgut will undergo a sequential pattern of rotations that is divided into three stages [4].
The first stage, begins around the 5th week, during which the rapid growth of the abdominal viscera leads to a greater component of the midgut external to the abdominal cavity.
In the 10th week, the gradual return of the midgut to the abdominal cavity as a result of its increase in size, marks the beginning of the second rotation stage.
The midgut has now rotated 90 degrees in a counterclockwise direction on the axis of the superior mesenteric artery (SMA), bringing the pre-arterial segment to the right side and the post-arterial segment to the left side of the abdominal cavity.
The following stage is essential to understand because the anomalies that occur at this stage will induce the malformations observed in our case.
Normally, the pre-arterial segment makes a further 180 degrees counter-clockwise behind the SMA, thus bringing it to the to the left side of the abdominal cavity, while the post-arterial segment, led by the coecum passes counterclockwise, anterior to the SMA into the right side of the abdomen.
Once all these rotations have been completed, The third stage represents the fusion of mesenteries and fixation of the midgut.
The first anomaly encountered in our patient and the least serious because it does not require special management is the complete common mesentery.
This anomaly is defined by an entire colon occupying the left half of the abdomen while the small intestine occupies the right side.
This is a consequence of the cessation of the rotation process of the post-arterial segment after the first 90 degrees during the second stage.
In contrast to the incomplete form, which is at risk of small bowel volvulus, the complete common mesentery does not lead to acute complications. It is often discovered in adulthood either incidentally or in the context of a digestive disease.
In our case, the mode of revelation was on the occasion of an acute complication secondary to the second intestinal rotation anomaly represented by left paraduodenal hernia.
Paraduodenal hernia, also known as mesocolic hernia, is the most frequent type of congenital internal hernia, and result from embryonic peritoneal anomalies and associated abnormal bowel rotation [5].
Left para-duodenal hernia (hernia of Lanzert) is about three times more common than the right counterpart (Waldayer’s hernia).it results from abnormalities in the rotation of the pre-arterial segment around the superior mesenteric artery during the second stage.
During this process, the bowel invaginates into an unsupported area of the descending mesocolon resulting in the anterior margin being formed by the ascending branch of the left colic artery and the inferior mesenteric vein [6].
The clinical presentation is non-specific, and may remain asymptomatic for a long time or present with non-specific symptoms, such as digestive disorders and chronic abdominal pain, to symptoms of intestinal obstruction [7].
Abdominal computer tomography(CT) is the modality of choice for positive diagnosis and severity and shows in typical images a cluster of dilated bowel segments with engorged and displaced mesenteric vessels at the hernial orifice [8].
In our case, the CT scan allowed the detection of both rotation anomalies, thus ensuring a preoperative diagnosis.
The only treatment for paraduodenal hernia is surgical, especially if the diagnosis was made during an acute intestinal obstruction.
The principle, being the reduction of the hernia and the closure of the orifice to prevent recurrence.
The orifice is usually closed with sutures, however, if it seems difficult, widening it to make it continuous with the peritoneal cavity constitutes an alternative [9].
Regardless of the type of repair, the laparoscopic approach in this type of situation offers several advantages for both the defnitive diagnosis, treatment of the hernia and its complication [10].
According to our review of the literature, nearly thirty cases of left paraduodenal hernia have been treated by laparoscopic surgery [10] and the various authors agree that this approach is safe and offers several advantages such as less postoperative pain, earlier intake of diet and shorter hospital stay as was the case for our patient.