COLLECTIVE REVIEW Intestinal Malrotation—Not Just the Pediatric Surgeon’s Problem Stephanie A Kapfer, MD, Joseph F Rappold, MD, FACS The classic description of intestinal malrotation is that rotation is unknown. Estimates in the literature range of the term infant who presents with bilious emesis. from 1 in 6,0007,8 to1in2009 of all live births. A series Upper gastrointestinal contrast study (UGI) confirms of consecutive barium enemas (BEs) performed as part the diagnosis by identifying the right-sided position of of an evaluation of a variety of abdominal complaints the duodenal–jejunal junction or evidence of a midgut identified nonrotation in 0.2% of all patients studied.10 volvulus. Treatment consists of the Ladd procedure.1 Autopsy studies suggest that some form of malrotation Unfortunately, diagnosis and treatment of intestinal may exist in 0.5% to 1% of the population.1,4,7 malrotation may not always be so straightforward. The What is certain is the fact that a significant percentage term itself refers not to a single congenital anomaly but of individuals with intestinal malrotation enter adult- rather to a spectrum of anomalies involving the position hood with it undetected. The percentage of these pa- and peritoneal attachments of the small and large intes- tients who will ultimately present with gastrointestinal tines. Diversity of anatomic configurations, ranging symptoms attributable to malrotation remains un- from a not-quite-normal intestinal position, to complete known. Clearly, all abdominal surgeons, not just those nonrotation, to reversed rotation, results in a wide vari- who specialize in pediatric disorders, should be familiar ety of clinical presentations and patients. with intestinal malrotation, its clinical presentation, di- The first cases of malrotation were reported in the agnosis, and treatment. literature in the mid-1700s.2,3 Progress on pathogenesis of the disease was not made until normal intestinal em- CASE REPORTS bryology was described, first by Meckel in 1817 and Patient 1 4,5 then more thoroughly by Mall in 1897. Our current A 22-year-old man presented with a history and physical understanding of intestinal development is reviewed in examination suggestive of acute appendicitis, with the 6 Figure 1. In a landmark 1923 article, Dott applied the exception of pain and tenderness localizing to the right embryologic discoveries to his experiences treating pa- upper quadrant. Preoperative CT demonstrated free tients with intestinal malrotation. He described the per- fluid and a small amount of free air in the subdiaphrag- tinent embryology and anatomic variations of malrota- matic spaces and in Morison’s pouch. A thickened ap- tion, and directly correlated his clinical observations pendix with surrounding inflammation was visualized with points of aberrant or failed embryologic develop- adjacent to the right inferior liver edge (Fig. 3). Opera- ment. Figure 2 presents a pictorial summary of the most tive findings confirmed perforated appendicitis in the common patterns of malrotation. setting of a subhepatic cecum. No significant length of Most cases of malrotation are discovered in the first ascending colon was identified, and the terminal ileum few months of life and 90% are discovered by 1 year of was fixed to the right posterior abdominal wall by retro- age. These figures do not reflect the patients who enter peritoneal attachments. The bowel was otherwise nor- adulthood undiagnosed.1,3,7 The true incidence of mal- mally rotated and fixed. No competing interests declared. Patient 2 The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of An 80-year-old man presented with pain and tenderness Defense, or the United States government. in the left upper quadrant and laboratory evaluation Received October 1, 2003; Revised April 21, 2004; Accepted April 21, 2004. consistent with an acute abdominal infection. CT dem- From the Department of Surgery, Naval Medical Center, San Diego, CA. onstrated a mass in the left upper quadrant that appeared Correspondence address: Joseph F Rappold, MD, FACS, Department of Surgery, Naval Medical Center, 34800 Bob Wilson Dr, San Diego, CA to lie between the transverse and left colon. Further ex- 92101. email: [email protected] amination of the CT revealed a pattern of malrotation in © 2004 by the American College of Surgeons ISSN 1072-7515/04/$30.00 Published by Elsevier Inc. 628 doi:10.1016/j.jamcollsurg.2004.04.024 Vol. 199, No. 4, October 2004 Kapfer and Rappold Intestinal Malrotation 629 Abbreviations and Acronyms BE ϭ barium enema SMA ϭ superior mesenteric artery SMVϭ superior mesenteric vein UGI ϭ upper gastrointestinal contrast study which the small intestine was located entirely in the right abdomen; the transverse, left, and sigmoid colon were in their normal positions; and the right colon was oriented transversely across the upper abdomen (Fig. 4). Within the cecum was the mass, a markedly irregular and thick- ened area that directly abutted the left anterior ribcage. It was highly suspicious for neoplasm, although an in- flammatory process could not be excluded. The patient was taken for exploratory laparotomy, during which an inflammatory mass involving the ce- cum and splenic flexure was found in the left upper quadrant.The origin of this phlegmon was a focal area of ischemic necrosis and perforation in the cecum. Other findings were consistent with the preoperative diagnosis of a mixed malrotation. Thin retroperitoneal bands at- tached the transverse colon to the right lateral abdomi- nal wall. The duodenum formed a C-loop around the head of the pancreas but did not cross midline. The remaining small bowel was found in the right lower quadrant. Patient 3 A 24-year-old woman with a history significant only for an appendectomy at age 10, presented to an outside institution with a 6-week history of crampy upper ab- dominal pain, nausea, and vomiting associated with oral Figure 1. Normal intestinal rotation. (A) By third week of fetal intake. She denied any chronic gastrointestinal com- development, primitive gut is divisible into three regions. These plaints. Her evaluation included normal right upper regions are the foregut (FG), midgut (MG), and hindgut (HG), each quadrant ultrasonography, esophagogastroduodenal en- with their respective blood supplies—celiac artery (CA), superior doscopy, and colonoscopy. CT was suggestive of malro- mesenteric artery (SMA), and inferior mesenteric artery (IMA). Dur- ing the first stage, the rapidly growing midgut herniates through the tation, which was confirmed by UGI. She underwent umbilical oraface (UO). (B) Duodenum rotates 90 degrees counter- exploratory laparoscopy, wherein a paraduodenal hernia clockwise, posterior to the SMA. Cephalad limb elongates, forming was discovered and reduced. multiple loops, and caudad limb remains relatively straight. (C) During the second stage, midgut returns to the abdominal cavity, Two weeks postoperatively, she presented to our insti- rotating an additional 180 degrees and pushing the hindgut to the tution complaining of persistent epigastric pain, nausea, left. (D) Cecum is the last portion to return, entering anterior to the and vomiting. Her symptoms did not resolve with con- SMA. (E) During the third stage, certain sections of the intestinal mesentery undergo a physiologic fusion and resorption, resulting in servative therapy and a workup for alternative causes was retroperitonealization of the supported structures. Right colon elon- unrevealing. Repeat UGI demonstrated an enlarged gates while assuming its retroperitoneal position. Left colon and stomach and small bowel that followed a winding course duodenum are also retroperitonealized. (F) The entire process re- down the right abdomen (Fig. 5). Delayed films con- sults in a midgut with a long, oblique mesenteric base (dotted line). firmed a left-sided colon. The patient was returned to 630 Kapfer and Rappold Intestinal Malrotation J Am Coll Surg Figure 2. Common anatomic configurations. (A) Isolated duodenal malrotation, (B) nonrotation, (C) mixed rotation, (D) reversed rotation with colon anterior to the superior mesenteric artery (SMA), (E) reversed rotation with colon posterior to the SMA, (F) hyperrotation, (G) hyperdescent, (H) inverted cecum, (I) subhepatic cecum, (J) intraperitoneal hernia. the operating room for exploratory laparotomy. Find- and proximal jejunum were straightened, and the small ings included residual hernia sac attachments and Ladd bowel mesentery was widened. bands involving the proximal small bowel and right co- lon. These attachments were divided, the duodenum DISCUSSION Clinical presentation In general, adults with malrotation present in one of three ways—with acute obstructive symptoms and signs of impending abdominal catastrophe, with chronic ab- dominal complaints that include both pain and inter- mittent obstruction, or with atypical symptoms from a common abdominal disease. Patients who present with bilious vomiting, abdomi- nal pain, fever, tachycardia, and peritoneal findings on physical examination should be suspected of having an evolving abdominal catastrophe. Confirmatory tests in- clude an elevated white blood cell count, acidosis with an elevated base deficit and lactate level, and pain that does not resolve with nasogastric tube decompression. These patients require rapid fluid resuscitation and ex- ploratory laparotomy or laparoscopy. The most com- Figure 3. CT image