Selected Articles from the Journal Abdominal Surgery

This article originally appeared in the Spring, 2007 issue of the Journal.

AXIAL VOLVULUS OF A GIANT MECKEL'S DIVERTICULUM

SHOWRI PALEPU, M.D., F.A.C.S.
CLINICAL ASSOCIATE PROFESSOR OF SURGERY
UNIVERSITY OF PITTSBURGH SCHOOL OF
MEDICINE
PITTSBURGH, PA

Correspondence To:
1801 LINCOLN WAY
MCKEESPORT, PA 15131

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INTRODUCTION
Meckel's diverticulum is the vestigial remnant of the vitelline (omphalomesenteric) duct. It is the most common congenital anomaly of the gastrointestinal tract in human beings. In the pediatric population it is the most common cause of massive lower gastrointestinal bleeding. The diverticulum is mostly dormant and is an incidental finding at laparotomy in the adult population. However, spontaneous axial volvulus of the Meckel's diverticulum will result in strangulation of this organ.

ABSTRACT
Meckel's diverticulum (persistent vitelline duct) is the most common congenital anomaly of the gastrointestinal tract in humans, occurring in about 2% of the general population. This anomaly devoid of any symptoms and totally unsuspected until incidentally found at small bowel contrast study, laparoscopy/laparotomy for unrelated reasons or until complications arising from the diverticulum require treatment. Although intestinal obstruction is the most common complication associated with Meckel's diverticulum in adults, isolated spontaneous axial volvulus of the diverticulum is probably the most uncommon complication involving this organ. The volvulus of Meckel's diverticulum is unique in that both organoaxial and mesoaxial torsion of the organ occur in the same setting, resulting in rapid progression of the diverticulum to gangrene and perforation.

CASE REPORTS
The patient is a 24 year old white female, admitted with a history of lower abdominal pain, nausea, bilious vomiting and constipation for five days. She stated that approximately two weeks prior to the start of the illness she had the “flu” with diarrhea. The abdominal pain initially was intermittent and colicky in nature, but later became steady and localized in the right lower quadrant. She had two bouts of dark blood per rectum on the day of admission. There was no history of fever or chills. She has been sexually active but not on contraceptives. Her last menstrual period was two weeks prior to admission. The past medical and surgical histories were noncontributory. Personal and family histories were unremarkable. Physical examination revealed an alert, oriented, dehydrated young white female in severe abdominal distress. Her vital signs were: Temperature of 99, pulse rate of 110/m, respiratory rate of 18/m and blood pressure 100/70mm Hg. Her oral mucosa and tongue were dry. The head and neck examination was normal. Examination of the heart and lungs was normal. The abdomen was distended with high pitched bowel sounds and was markedly tympanic on percussion. The right lower quadrant was very tender with rebound tenderness. Groins are negative for herniae. Pelvic and rectal examinations were normal.

Her urine specific gravity was 1030, otherwise the urinalysis was normal. Her hemoglobin was 16.2 gm/dl with a hematocrit of 42.1%. The total white blood cell count was 12,300/cu mm with 67% neutrophils and 21% bands. The serum electrolytes revealed sodium 124 meq/L and chloride 90meq/L. The serum pregnancy test was negative. The plain X-rays of the abdomen showed findings consistent with a mechanical small bowel obstruction (fig 1&2)

With these clinical, radiological and laboratory findings, an acute surgical abdomen was diagnosed: [ acute gangrenous appendicitis with small bowel obstruction or acute Crohn's ileitis with bleeding.] After correction of fluid and electrolyte imbalance a celiotomy was performed which revealed distal small bowel obstruction at the level of the Meckel's diverticulum; the appendix was normal. A giant Meckel's diverticulum was found to have undergone spontaneous axial volvulus resulting in strangulation (Fig 3). The segment of the ileum bearing the volvulized Meckel's diverticulum was resected using a GIA stapler (fig 4) and a side to side stapled reconstruction of the ileum was performed.

The post operative course was uneventful and the patient was discharged on the fifth post operative day. The final pathology report revealed a Meckel's diverticulum measuring 11cms in length that had undergone axial volvulus resulting in strangulation (Fig 5). No tumor or ulcer was noted in the resected specimen.

DISCUSSION
Heronymus Fabricus was the first to describe a distal ileal diverticulum in 1598¹, but the first detailed description of the ileal diverticulum with elucidation of its embryologic significance was made by Johann Friedrick Meckel (the younger) in 1809², hence diverticulum bears his name.

Prior to the development of the functioning placenta, the main source of nourishment for the early human embryo is from the yolk sac. The communication between the yolk sac and the embryonic gut is called the vitalline (omphalomesenteric) duct. Normally involution and obliteration of the vitalline duct occurs between the fifth and seventh weeks of gestation.³ Failure of this process of involution occurs in about 2% of human beings. The persisitent vitalline duct anomaly is considered as the most common congenital anomaly of the gastrointestinal tract.⁴ Failure of closure of the entire vitalline duct results in an umbilical-fecal fistula. Proximal closure of the vitelline duct results in an umbilical sinus, whereas distal persistence of the vitelline duct results in Meckel's diverticulum. Meckel's diverticulum is situated on the antimesentric border of ileum approximately 90cm proximal to the ileocecal valve and is about 5cm in length. Being a congenital diverticulum, it bears all three layers of the intestinal wall (a true diverticulum) with its own arterial blood supply from the ileocolic artery, a branch of the superior mesenteric artery. Heterotopic tissue (gastric, pancreatic or both) may be present in 15 to 50% of specimens and tumor occurrence in the diverticulum is noted in 1 to 3% cases.⁵

The diverticulum may remain dormant and unsuspected until accidentally discovered at necropsy. In life, small bowel contrast studies, laparotomy or laparoscopy for unrelated reasons may bring this entity to light. Also complications primarily resulting from Meckel's diverticulum (ie. bleeding, obstruction, inflammation, perforation etc.) will draw clinician's attention to this organ.

In the analysis of specific complications arising from Meckel's diverticulum of 1605 collected cases by Moses,⁶ the frequency of the complications were: intestinal obstruction in 35% cases, bleeding in 32%, diverticulitis

in 22%, umbilical fistula in 10% and miscellaneous findings ( hernia, tumor, volvulus, etc,) in 1% of cases. Isolated spontaneous axial volvulus of Meckel's diverticulum is extremely rare and results in rapid progression to strangulation.⁷ Unusually long Meckel's diverticulum with a narrow base predisposes it to volvulus. A volvulus is an abnormal torsion of a viscus organ that can be organoaxial or mesoaxial. The sigmoid colon is the most common intra-abdominal hollow viscus to undergo a volvulus where as Meckel's diverticulum probably the most uncommon intra-abdominal counterpart to undergo volvulus.⁸ Meckel's diverticulum is unique in that it exhibits both organoaxial and mesoaxial mechanisms of torsion in the same setting. This results in a dual problem of closed loop formation and circulatory compromise of the viscus leading to rapid progression to strangulation. Primary neoplasms of Meckel's diverticulum are rare, seen in only 1 to 3% cases. Benign tumors arising from Meckel's Diverticulum may predispose the organ to volvulus. Leiomyoma⁹ is the most common benign tumor arising from the Meckel's diverticulum whereas fibroma¹⁰ ranks second. Malignant tumors (adenocarcinomas, carcinoids and sarcomas¹¹) arising from Meckel's diverticulum may be less likely to predispose the organ to volvulus because of their infiltrating nature.

SUMMARY
Meckel's diverticulum is the vestigial remnant of the vitelline duct, seen approximately in 2% of the population and considered the most common congenital anomaly of the gastrointestinal tract. Common complications arising from Meckel's diverticulum are intestinal obstruction, hemorrhage, and diverticulitis. Probably the most uncommon complication arising from the diverticulum is volvulus. Axial volvulus of Meckel's diverticulum is unique in that both organoaxial and mesoaxial torsion occurs in the same setting resulting in rapid progression of the organ to strangulation.

Figure 1

Figure 2

Figure 3

Figure 4 (left) Figure 5 (right)

REFERENCES

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( 2.) Bailey & Love's short practice of surgery, Rains & Cooper, Lewis London 1971, 15: 918-920

(3.) Amoury RA: Meckel's Diverticulum in Welch KJ et al(eds) : Pediatric Surg. Ed 4, Vol 2, Chicago, Yr Book Medical, 1986.

(4.) Benson D.D., Surgical Implications of Meckel's Diverticulum. IN Ravich M.M., Welch K.J. Benson C.D., Et Al: Pediatric Surgery Ed 3, Chicago Year Book of Medical Publishers, 1979 pp 955-960.

(5.) Moore GP, Burkle MF, : Isolated Axial Volvulus of a Meckel's Diverticulum, Am. J of Emergency Med. 6: 2 March 1988.

(6.) Moses W.R. Meckel's Diverticulum. N. Eng. J. Med., 237: 118-122, 1947.

(7.) Guss AD, Hoyt BD,: Axial Volvulus of Meckel's Diverticulum: A Rare Cause of Acute Abdominal Pain, Annis of Emerg Med 16:7 July 1987

(8.) Bronen Ar, Glick S, Teplick S, : Meckel's Diverticulum Axial Volvulus Mimicking Emphysematous cholecystitis, The AM. J. of Gastroenterology 79:3 1984.

(9.) Sayfan J, BorowskyA, Halevy, Oland J, : Volvulus Due to a Tumor of Meckel's Diverticulum. J of Clin Gastroenterology 7 (4): 314-317, 1985.

(10.)Almagro AU, Erickson Jr L, : Fibroma in Meckel's Diverticulum: A Case Associated with Axial and Ileal Volvulus. Am. J. of Gastroenterology 77-7, 1982.

(11.)Niv Y, Avid-Abu S, Kopelman C, Oren M, : Torsion of Leiomyosarcoma of Meckel's Diverticulum. The Am. J. of Gastroenterology. 81:4, 1986