Intestinal malrotation is a

congenital A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities c ...

anomaly of rotation of the

midgut The midgut is the portion of the embryo from which most of the intestines develop. After it bends around the superior mesenteric artery, it is called the "midgut loop". It comprises the portion of the alimentary canal from the end of the foregut ...

. It occurs during the first trimester as the fetal gut undergoes a complex series of growth and development. Malrotation can lead to a dangerous complication called

volvulus A volvulus is when a loop of intestine twists around itself and the mesentery that supports it, resulting in a bowel obstruction. Symptoms include abdominal pain, abdominal bloating, vomiting, constipation, and bloody stool. Onset of symptoms m ...

. Malrotation can refer to a spectrum of abnormal intestinal positioning, often including: * The

small intestine The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through t ...

found predominantly on the right side of the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the tors ...

* The

cecum The cecum or caecum is a pouch within the peritoneum that is considered to be the beginning of the large intestine. It is typically located on the right side of the body (the same side of the body as the appendix, to which it is joined). The w ...

displaced from its usual position in the right lower quadrant into the epigastrium or right hypochondrium * An absent or displaced ligament of Treitz * Fibrous peritoneal bands called bands of Ladd running across the vertical portion of the

duodenum The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine ...

* An unusually narrow, stalk-like

mesentery The mesentery is an organ that attaches the intestines to the posterior abdominal wall in humans and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines ...

The position of the intestines, narrow mesentery and Ladd's bands can contribute to several severe gastrointestinal conditions. The narrow mesentery predisposes some cases of malrotation to midgut volvulus, a twisting of the entire small bowel that can obstruct the mesenteric blood vessels leading to intestinal

ischemia Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dig ...

, and death if not promptly treated. The fibrous Ladd's bands can constrict the duodenum, leading to intestinal obstruction.

Signs and symptoms

Signs and symptoms of malrotation vary depending on if the patient is suffering from an acute volvulus or experiencing chronic symptoms. * If the patient, most often an infant, presents acutely with midgut volvulus, it is usually manifested by bilious

vomiting Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteri ...

, crampy abdominal pain, abdominal distention, and in late cases, the passage of blood and

mucus Mucus ( ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It ...

in their stools. * Patients with chronic, uncorrected or undiagnosed malrotation can have recurrent abdominal pain and vomiting. * Malrotation may be asymptomatic.

Complications

Intestinal malrotation can lead to a number of disease manifestations and complications such as: * Acute midgut volvulus * Chronic midgut volvulus * Acute duodenal obstruction * Chronic duodenal obstruction * Short bowel syndrome, in cases of volvulus with intestinal necrosis * Death, in cases of volvulus with pan-necrosis of the bowel, severe

septic shock Septic shock is a potentially fatal medical condition that occurs when sepsis, which is organ injury or damage in response to infection, leads to dangerously low blood pressure and abnormalities in cellular metabolism. The Third International Co ...

or hypovolemic shock *

Malabsorption Malabsorption is a state arising from abnormality in absorption of food nutrients across the gastrointestinal (GI) tract. Impairment can be of single or multiple nutrients depending on the abnormality. This may lead to malnutrition and a variety ...

* Chronic

motility Motility is the ability of an organism to move independently, using metabolic energy. Definitions Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ...

issues * Internal herniation *

Superior mesenteric artery syndrome Superior mesenteric artery (SMA) syndrome is a gastro-vascular disorder in which the third and final portion of the duodenum is compressed between the abdominal aorta (AA) and the overlying superior mesenteric artery. This rare, potentially life ...

Causes

The exact cause of intestinal malrotation is unknown. It is not definitively associated with a particular gene, but there is some evidence of recurrence in families.

Diagnosis

Malrotation is most often diagnosed during infancy, however, some cases are not discovered until later in childhood or even adulthood. With acutely ill patients, consider emergency surgery

laparotomy A laparotomy is a surgical procedure involving a surgical incision through the abdominal wall to gain access into the abdominal cavity. It is also known as a celiotomy. Origins and history The first successful laparotomy was performed without ...

if there is a high index of suspicion. In cases of volvulus, plain radiography may demonstrate signs of duodenal obstruction with dilatation of the proximal duodenum and stomach but it is often non-specific. Ultrasonography may be useful in some cases of volvulus, depicting a "whirlpool sign" where the

superior mesenteric artery In human anatomy, the superior mesenteric artery (SMA) is an artery which arises from the anterior surface of the abdominal aorta, just inferior to the origin of the celiac trunk, and supplies blood to the intestine from the lower part of the ...

and

superior mesenteric vein In human anatomy, the superior mesenteric vein (SMV) is a blood vessel that drains blood from the small intestine ( jejunum and ileum). Behind the neck of the pancreas, the superior mesenteric vein combines with the splenic vein to form the hepat ...

have twisted. Upper gastrointestinal series is the modality of choice for the evaluation of malrotation, as it will often show an abnormal position of the duodenum and duodeno-jejunal flexure ( ligament of Treitz). In cases of malrotation complicated with volvulus, upper GI demonstrates a corkscrew appearance of the distal duodenum and jejunum. In cases of obstructing Ladd's bands, upper GI may reveal a duodenal obstruction. Although upper GI series is regarded as the most reliable diagnostic test for intestinal malrotation, false negatives may occur in 5% of cases. False negatives are most frequently attributed to radiographer error, uncooperative pediatric patients, or variations in intestinal positioning. In equivocal cases physicians may wish to repeat the upper GI or consider additional diagnostic modalities. Lower gastrointestinal series, may be helpful in some patients by showing the caecum at an abnormal location.

CT scan A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

and magnetic resonance imaging may also aide in the diagnosis of equivocal cases. The incidence of intestinal malrotation in infants with omphalocoele is low. Therefore, there is little evidence to support the screening for intestinal malrotation in infants with omphalocoele.

Treatment

Prompt surgical treatment is necessary for intestinal malrotation when volvulus has occurred: * First, the patient is resuscitated with fluids to stabilize them for surgery * The volvulus is corrected (counterclockwise rotation of the bowel), * The fibrous Ladd's bands over the

are cut, * The mesenteric pedicle is widened by separation of the duodenum and cecum, * The small and large bowels are placed in a position that reduces their risk of future volvulus With this condition the appendix is often on the wrong side of the body and therefore removed as a precautionary measure during the surgical procedure. This surgical technique is known as the "Ladd's procedure", after Dr. William Ladd. Long-term research on the Ladd's procedure indicates that even after surgery, some patients are susceptible to GI issues and may need further surgery.

References

External links

{{DEFAULTSORT:Intestinal Malrotation Congenital disorders of digestive system