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The presence of a volvulus was apparent on laparotomy. Tuberculosis may involve the mesentery but has not been described with volvulus. Mesenteric lymphangiomatosis (which is a congenital malformation of the lymphatic channels) and mesenteric lipoma (which is a benign neoplasm) both may act as a lead point for volvulus but would not account for the whitish discoloration seen nor the whitish fluid in the abdomen. Laparotomy revealed a midgut volvulus with the bowel torsed twice around its mesenteric blood supply. Detorsion of the bowel led to resolution of the whitish coloration of the mesentery, confirming that the color was related solely to a mechanical lymphatic obstruction.
Normal intestinal rotation and attachment begins during the fifth gestational week and involves a series of steps during which the bowel extrudes into the umbilical cord and undergoes counterclockwise rotation around the superior mesenteric artery as it returns to the peritoneal cavity where fixation occurs. Malrotation is the term that describes the situation when normal rotation and fixation do not occur, predisposing the bowel to volvulization around the superior mesenteric artery and superior mesenteric vein, leading to intestinal obstruction and strangulation of the mesenteric blood flow. The role of the physician looking after a child with an acute abdomen is to consider volvulus early and initiate rapid confirmatory imaging.
Regarding imaging, there are several tests to consider. Abdominal plain films are often obtained that may demonstrate duodenal obstruction, but in most situations will not lead to a specific diagnosis. While the contrast enema was previously used, the upper gastrointestinal tract series has emerged as the study of choice, with findings that suggest volvulus including duodenal obstruction with or without a duodenojejunal corkscrew twist. However, other tests have also been demonstrated to provide useful information. Ultrasound may demonstrate a reversal of the superior mesenteric artery and superior mesenteric vein in volvulus. And, as in our case, computed tomography may also demonstrate abnormal vessel orientation as well as dilated small bowel, small bowel located on the right and large bowel located on the left side of the abdomen, and bowel twisting that is referred to as a whirl sign.1
The definitive therapy consists of surgery, with the principal operation being a procedure originally pro-posed in 1936 by William Ladd and bearing his name.2 It involved detorsion of the bowel in a counterclockwise direction, dissection of band crossing from the cecum over the duodenum to the lateral peritoneal gutter (Ladd bands), broadening of the mesentery, placement of the cecum in the left upper quadrant, and placement of the small bowel in the right side of the abdomen, thus “restoring an earlier state of embryologic development.” Further, as the appendix would be placed in a nonstandard location, it is usually removed as part of the operation to avoid future diagnostic confusion. There are some case reports in which volvulus is associated with chylous ascites3 but not the mesenteric engorgement with chyle.
On discussion with the family after surgery, the parents relayed that, a few hours prior to the onset of abdominal pain, the child had ingested a large bowl of custard-type vanilla ice cream, which had a high fat content. The ingestion of ice cream was sufficient to provide a bolus of fat to almost entirely fill the mesenteric lymphatic channels.4 Further, the meal occurred with enough time for chyle to enter the small-bowel mesentery before it was trapped by the volvulus and had a chance to be absorbed into the portal circulation. Further, the pressure of the chyle in the lymphatic channels was sufficient to lead to leak into the peritoneal cavity and to chylous ascites. Detorsion of the intestine led to the chyle being absorbed into the circulation and resolution of the discoloration of the mesentery.
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Correspondence: Kenneth W. Gow, MD, 4800 Sand Point Way NE, Mailstop W-7729, PO Box 5371, Seattle, WA 98145 (firstname.lastname@example.org).
Accepted for Publication: February 6, 2010.
Author Contributions:Study concept and design: Cateriano and Gow. Acquisition of data: Gow. Analysis and interpretation of data: Cateriano and Gow. Drafting of the manuscript: Cateriano and Gow. Administrative, technical, and material support: Gow. Study supervision: Gow.
Financial Disclosure: None reported.
Image of the Month—Diagnosis. Arch Surg. 2011;146(5):630. doi:10.1001/archsurg.2011.107-b