Case Presentation CC: vomiting, abdominal pain PI: 49 y/o man who 36 hours prior to admission had the onset RUQ abdominal pain. Pain worsened, went to ER 4 hours later. CBC, SMA, LFT’s, amylase, lipase all normal. Abdominal sono normal. Some relief after GI cocktail, discharged. 49 year old man 3 wks prior to admission had 1 episode of vomiting 3 hours after eating foie de gras and had not felt completely normal since but no further n/v or abdominal pain. On the day prior to admission (4/29/04) he had sudden onset of right upper abd pain with no know cause. The pain was sharp and radiated to the back. The pain subsided after a n hour and he proceeded to go on a planned trip to Fredricksburg but his pain intensified and he went to the ER there. In the ER he had a negative workup including abdominal ultrasound, CBC, chemistries, amylase and lipase. He had a partial relief after a GI cocktail and was sent home to his hotel with Phenergan and Lortab.

Case Presentation Night prior to admission, pain recurred associated with vomiting. Next am, ER- repeat testing normal, discharged. Admitted PHD due to continuing pain and vomiting. No hematemesis or blood in stool, fever, diarrhea or constipation. No prior history of similar symptoms. That night he had n/v x2 with increased pain so he went back to the ER the next morning but all tests were again negative. He drove back to Dallas where he was directly admitted on 4/30 due to ongoing vomiting and pain. He denied having diarrhea, constipation or fever. No SOB or chest pain.

Case Presentation PMHx- no prior abdominal surgery, only history of GI problems is occasional GERD. History of seizure disorder and mild depression. Meds- Tegretol, Celexa, ASA 81mg, Pepcid prn ETOH- avg 1 drink/ day PMHx- no prior abdominal surgeries. No history of abdominal pain other than that in the present illness but has had some reflux symptoms, especially with fatty foods. Positive history of seizure disorder and depression, controlled with meds

Case Presentation PE- 120/72, HR 66, T 98.4 Normal exam except abdomen tender, voluntary guarding RUQ and periumbilical. No rebound. No hepatosplenomegaly, mass. BS’s reduced. Labs- normal abd. sono, LFT’s, amylase, lipase. Normal lytes. Bun/Cr= 11/1.2. WBC 7.2K, Hgb 14.6 Normal HIDA scan. Obstructive series- multiple air/ fluid levels seen throughout the small bowel consistent with partial small bowel obstruction

Case Presentation Working diagnosis: distal small bowel obstruction of uncertain etiology Initial course- NG tube placed, IV fluids, IV PPI. CT scan- distended small bowel consistent with distal partial small bowel obstruction. Appendix and colon normal. Surgery consult obtained. Pain and nausea resolved after placement of NG tube. Surgical consult was obtained.

Causes of Intestinal Obstruction 1. Intrinsic Bowel Lesions A. Congenital- atresia / stenosis, malrotation, duplications/cysts B. Inflammatory Diverticulitis, TB, actinomycosis    Crohn’s disease     Ischemia     Radiation injury     Chemical (e.g., potassium chloride)     Endometriosis     Postanastomotic   C. Intussusception   D. Obturation     Polypoid neoplasms     Gallstones     Foreign bodies     Bezoars     Feces   E. Neoplastic stricture II. Extrinsic Bowel Lesions   A. Congenital bands   B. Adhesions (usually postoperative)  C. Hernias (inguinal, femoral, ventral, umbilical, diaphragmatic)   D. Volvulus/ torsion E. Carcinomatosis, extraintestinal neoplasm   F. Intra-abdominal abscess

Next day- no improvement in x-ray findings, patient taken to surgery. Case Presentation Next day- no improvement in x-ray findings, patient taken to surgery. Surgical findings: dilated prox sm. bowel with bruising and torsion of the small bowel due to a Meckel’s diverticulum as the lead point for the torsion. The Meckel’s diverticulum was resected.

Meckel’s Diverticulum Phillip M Aronoff, M.D.

Meckel’s Diverticulum Most common congenital abnormality of the gastrointestinal tract Remnant of the vitelline duct antimesenteric border of the ileum Often contain heterotropic tissue- gastric, occasionally pancreatic Vast majority of Meckel’s diverticuli are clinically silent Meckel’s diverticlum is the most common congenital abnormality of the gastrointestinal tract. Remnant of the vitelline duct which attaches the fetal small intestine to the umbilicus. First described in detail by Johann Meckel in 1809, it is found withing 45 to 60cm of the ileocecal valve and is located on the antimesenteric border of the ileum. Size of the diverticulum varies from a small bump to a long projection which may connect to the umbilicus by a fibrous cord. Some vitelline duct cells are pluripotent so it is common for the diverticulum to contain heterotropic tissue, the most common being gastric mucosa (50% of all Meckel’s diverticulum), pancreatic tissue in 5% and less commonly colonic mucosa.

Meckel’s Diverticulum Rule of 2’s 2% of the population have one 1/2 of symptomatic lesions usually present before the age of 2 years old, others most commonly in the first 2 decades of life Diveriticuli in adult patients only become symptomatic in about 2% 2 times more common in males than females Usually found within 2 feet of the ileocecal valve Usually are about 2 inches in length 1/2 contain heterotrophic mucosa (usually gastric, occasionally pancreatic)

Meckel’s Diverticulum Clinical presentation Lower GI bleeding due to ulceration by heterotopic gastric mucosa Intestinal obstruction due to internal segmental volvulus or intussusception Local inflammation with or without perforation resembling appendicitis due to diverticulitis Rare presentations: Neoplasms

Meckel’s Diverticulum Lower GI bleeding due to ulceration by heterotrophic gastric mucosa 25-50% of symptomatic presentations Usually painless Episodic Hematochezia (usually maroon but may be tarry or bright red) Not infrequently massive bleeding- occult bleeding is rare Most common cause of small intestinal hemorrhage in patients under 30 y/o Meckel’s scan is often positive patients

Meckel’s Diverticulum Intestinal obstruction due to internal segmental volvulus or intussusception 20-30% of symptomatic presentations More common in older patients Diverticulum acts as a lead point causing entero-entero or entero-colonic intussusception which often cannot be reduced hydrostatically. This may present with “currant jelly” like stool and a palpable mass may be present If volvulus can be reduced hydrostatically, the patient should still have a surgical resection. If diverticulum is connected to umbilicus by fibrous cord, this may act as a focal point for internal herniation of the small bowel or secondary volvulus. Volvulus is acute and may result in strangulation of the bowel if not treated (Our patient presented with obstruction. On pathology, no acute inflammation was seen in the diverticulum and no heterotrophic epithelium was found.)

Meckel’s Diverticulum Local inflammation with or without perforation due to Meckel’s diverticulitis 10-20% of symptomatic presentations Usually adult patients Usually due to ectopic acid producing gastric mucosa causing significant ulceration and possible perforation. This may occasionally be related to H. Pylori infection of the mucosa. Rarely caused by perforation due to a foreign body in the diverticulum. Usually these patients are thought to have appendicitis prior to surgery

Meckel’s Diverticulum Rare Presentations- neoplasms arising in the diverticulum Benign- (most common) Leiomyomas Angiomas Lipomas Malignant- Adenocarcinoma- usually from the gastric mucosa Sarcoma Carcinoid tumor

Meckel’s Diverticulum Diagnostic studies Difficult diagnosis Most accurate test, especially in children, is “Meckel’s scan”- sodium 99-Tc-pertechinetate, taken up by gastric mucosa (sensitivity 85%, specificity 95%, accuracy 90% in pediatric patients) Less accurate in adults due to reduced prevalence of ectopic gastric mucosa in the diverticulum causing false negatives. Accuracy improved by giving pentagastrin (increases metabolism of mucus producing cells), glucagon or H2 blockers (reduce peristalsis and secretions that may flush out the radionuclide) In adults with a negative scan, abdominal CT scan is often helpful in cases of obstruction by showing a site of high grade partial bowel obstruction in the distal ileum. If CT is negative barium studies should be performed which may show the diverticulum (do not do prior to Meckel’s scan as barium may interfere) If bleeding with a negative scan, angiography may be helpful Our patient would have had a negative scan and not at risk for bleeding or inflammation due to lack of heterotropic gastric mucosa.

Meckel’s Diverticulum Treatment If symptomatic, prompt surgical intervention to resect the diverticulum or segment of ileum containing the diverticulum. If bleeding, the source of bleed is often in the segment of ileum adjacent to the diverticulum. If not symptomatic and found incidentally at surgery in children under 2 y/o, resection is recommended. In asymptomatic adults, resection is controversial since only about 2% of these patient’s will become symptomatic and there is about a 2% incidence of short or long term complications (stenosis, adhesions) after prophylactic resection.

Meckel’s Diverticulum Phillip M Aronoff, M.D.