ABSTRACT
Intestinal malrotation is a congenital anomaly of the midgut. The incidence of intestinal malrotation is 1 in 500 live births. It is rarely seen in adults. Most of the symptomatic patients present with acute bowel obstruction, intestinal ischemia or chronic vague abdominal pain. We present a 49-year-old male presenting with the findings of acute intestinal obstruction.
Introduction
Intestinal malrotation is a congenital anomaly of the midgut. Malrotation is defined as nonrotation or incomplete rotation of the midgut around superior mesenteric artery. The incidence of intestinal malrotation is 1 in 500 live births (1).
Most symptomatic patients present with acute bowel obstruction, intestinal ischemia or chronic vague abdominal pain. It occurs predominantly in infants and rarely in adults (2,3). However, adult-age midgut malrotation is difficult to diagnose and should be kept in mind in differential diagnosis of acute abdomen due to its nonspecific presentation.
We present a 49-year-old male presenting with the findings of acute intestinal obstruction.
Case
A Forty-nine-year-old male was presented to our emergency department with the complaints of progressive abdominal distention, multiple episodes of vomiting, severe, generalized and colicky abdominal pain for the past five days. The patient also complained of non-passage of flatus and motion for the past two days. There was no history of previous surgical intervention or any medical comorbidity.
On physical examination, his vital signs were as follows: pulse: 86 bpm, blood pressure: 135/72 mmHg, and respiratory rate: 20 per minute. The temperature was 37.40C. Distended abdomen and mild generalized tenderness to deep palpation were present with voluntary guarding. Bowel sounds were absent. Rectal examination was unremarkable.
The patient’s laboratory tests demonstrated a hemoglobin level of 16.9 g/dL, leukocyte count of 15.850/mm3 with prominent neutrophilia, C-reactive protein value of 197.6 mg/L, and urea level of 72.6 mg/dL. All other basic biochemical parameters were within the normal limits. Abdominal X-rays at presentation showed distended small bowel and multiple air fluid levels suggestive of intestinal obstruction (Figure 1). This was subsequently confirmed via an abdominal ultrasound. The patient was managed with nasogastric decompression and intravenous fluid support, but there was no improvement in symptoms. Abdominal computed tomography revealed gross dilatation of the small bowel and large bowel predominantly on the left side. The caecum and ileocaecal junction were located in left iliac fossa (Figure 1, 2).
The patient was planned for surgery and laparotomy was performed. Surgical findings confirmed dilatation of the small bowel and all colon segments with the caecum found on the left side of the abdomen (Figure 3). The mobile mesentery was fixed. Midgut volvulus in a clockwise direction was found. The volvulus was untwisted completely in a counter-clockwise direction and then the viability of the bowel was assessed. Segmented massive gangrene of the small bowel was present. A forty cm area of necrotic small intestine from 10 cm proximal of the terminal ileum was resected and the abdomen was then closed. The patient was discharged on the fifth postoperative day with no complication.
Discussion
Intestinal malrotation is a rare condition more rarely presenting in late adulthood. It presents usually in the neonatal period and early childhood. Seldom have been the cases of malrotation presenting in adulthood as obstruction been reported (4). The normal rotation of intestinal development has been divided into three stages. Stage one occurs between five and ten weeks of gestation. It includes extrusion of the midgut into the extra-embryonic cavity, a 90°C counterclockwise rotation, and return of the midgut into the fetal abdomen. Stage two occurs in week 11 and involves further counter-clockwise rotation within the abdominal cavity, completing a 270° rotation. This rotation brings the duodenal “C” loop forms behind the superior mesenteric artery with the ascending colon to the right, the transverse colon above, and descending colon to the left. Stage three involves fusion and anchoring of the mesentery. The caecum descends, and the ascending and descending colon attach to the posterior abdominal wall. According to this concept, cases of failure of rotation will involve the entire midgut, and a classical and severe malposition will result, with the small bowel located on the right side and the colon on the left side of the peritoneal cavity. Stage one anomalies include omphaloceles; Stage two anomalies involve nonrotation, malrotation, and reversed rotation. Stage three anomalies include unattached duodenum, mobile caecum, and unattached small bowel mesentery (5,6).
The presentation of intestinal malrotation in adults occurs in approximately 0.2-0.5% (1). Acute presentation is with volvulus of midgut or ileocecum. The chronic presentation includes chronic abdominal pain, bloating, vomiting, constipation and diarrhea (7). Diagnosis is made in the adult in the presence of chronic abdominal symptoms during surgery for acute abdomen, or incidentally during an imaging exam for no specific symptoms. The majority of midgut malrotation in adults remains asymptomatic throughout life (8). In asymptomatic patients with intestinal malrotation, observation is enough (9). In symptomatic adults with malrotation, midgut volvulus is the most common cause of acute abdomen. The treatment of a symptomatic malrotation is primarily surgical. Emergency exploration and resection of the necrotic bowel is important for survival (7). There is no standard operation mentioned in the literature or textbooks covering the treatment of a typical malrotation (4).
As a conclusion, midgut malrotation occurs rarely in adults. Therefore, midgut malrotation in adults is difficult to diagnose and should be kept in mind in differential diagnosis of acute abdomen due to its nonspecific presentation.
