Intestinal malrotation with acute appendicitis

A 36-year-old male admitted to the emergency department with abdominal pain around the umbilicus and in the left lower quadrant without any rebound.

Abdominal CT with IV contrast demonstrated that not only the duodenojejunal junction but also the jejunal loops have deviated to the right quadrant of the abdomen whereas the ileocecal valve was in the left lower quadrant (Fig.1,3). Superior mesenteric artery (SMA)  was located to the right of the superior mesenteric vein (SMV) (Fig.2). These findings were consistent with the malrotation.

Also, the appendix extended from the left lower quadrant to the midline of the abdomen, measuring approximately 7.5 mm at its thickest portion (Fig.4a,4b). Also, there was periappendiceal fat standing compatible with acute appendicitis (Fig.4c).

Acute appendicitis is probably the most common intraabdominal condition requiring emergency surgery. In its typical presentation, acute appendicitis begins with a vague abdominal discomfort around the epigastric or periumbilical region.

Appendicitis causing pain in the left lower quadrant is extremely rare and can occur with congenital malformation.  The majority of cases with left lower abdominal pain are described to be associated with congenital midgut malrotation, situs inversus, or an extremely long appendix.

For midgut malrotation with the heart and liver on the correct sides, CT is useful in demonstrating this anomaly. The presence of CT  SMV rotation sign, with the SMV located anterior and to the left of the SMA as well as the duodenojejunal junction position

is helpful to ascertain the presence of midgut malrotation. The CT findings of left-sided and right-sided appendicitis are similar in appearance except for their location. For right-sided appendicitis with abnormal length projecting into the left lower quadrant of the abdomen, it is important to identify the cecum on CT so that an abnormal appendiceal location can be recognized.

CT findings seen in acute appendicitis are dilated appendix with a distended lumen, thickened and enhancing wall, peri-appendiceal inflammation, extraluminal fluid, inflammatory phlegmon and appendicolith.

In our case, duodenojejunal junction was not positioned to the left of spine as it is expected and the cecum was at the left lower quadrant. The SMA/SMV relationship was also reversed. These findings are compatible with intestinal malrotation.

Also the diameter of the appendix was measured as 7.6 mm at its widest point and there was a slight peri-appendiceal inflammation compatible with acute appendicitis.

In conclusion, our case demonstrates atypical presentation of acute appendicitis that can be a cause of delayed/missed diagnosis especially with physical examination alone since pain at left lower quadrant was unusual for appendicitis. Atypical presentations of acute abdominal conditions superimposed on asymptomatic gastrointestinal malrotation can result delay for proper diagnosis/therapy and potentially increase morbidity and mortality. Therefore, early diagnosis becomes important to prevent complications of acute appendicitis.