Rosen & Barkin's 5-Minute Emergency Medicine Consult (442 page)

• 055.0 Postmeasles encephalitis
  
• 055.1 Postmeasles pneumonia
  
• 055.9 Measles without mention of complication
  

BASICS

• Most common congenital abnormality of the GI tract
  
  • Results from incomplete obliteration of the omphalomesenteric duct
    
• True diverticula (contains all layers):
  
  • 50% contain normal ileal mucosa.
    
  • 50% contain either gastric (most common), pancreatic, duodenal, colonic, endometrial, or hepatobiliary mucosa.
    
• Rule of 2’s:
  
  • 2% prevalence in general population
    
  • 2% lifetime risk for complications, decreasing with age
    
  • Symptoms commonly occur around 2 yr of age:
    
    • 45% of symptomatic patients <2 yr old
      
  • Average length 2 in
    
  • Found within 2 ft of the ileocecal valve
    
• Male-to-female ratio approximately equal, but more often symptomatic in males
  
• Complications:
  
  • Obstruction and diverticulitis in adults
    
  • Hemorrhage and obstruction in children
    
  • Mean age 10 yr
    
  • Current mortality rate 0.0001%
    
  • Occurs more frequently in males
    
• Obstruction:
  
  • Diverticulum attached to the umbilicus, abdominal wall, other viscera, or is free and unattached, leading to:
    
    • Intussusception: Diverticulum is the leading edge.
      
    • Volvulus: Persistent fibrous band leads to bowel rotation.
      
• Diverticulitis:
  
  • Opening obstructed
    
  • Bacterial infection follows.
    
  • Presents like appendicitis (most common preoperative diagnosis with Meckel diverticulum)
    

• Most common cause of significant lower GI bleeding in children.
  
• Presents at age <5 yr with episodic painless, brisk, and bright-red rectal bleeding.
  

Remnant of the omphalomesenteric duct that typically regresses by week 7 of gestation.

DIAGNOSIS

• 3 different types of presentation:
  
  • Rectal bleeding
    due to hemorrhage, which results from mucosal ulcerations within the ectopic gastric tissue
    
  • Vomiting
    due to obstruction secondary to volvulus, intussusceptions, or intraperitoneal bands
    
  • Abdominal pain
    (appendicitis like) due to an inflamed or perforated diverticulum
    
• General:
  
  • Fever
    
  • Malaise
    
  • Weakness
    
  • Fatigue
    
• GI:
  
  • Classically painless rectal bleeding
    
  • Abdominal pain:
    
    • Location depends on cause
      
    • Appendicitis like
      
  • Vomiting
    
  • Distention
    
  • Changes in bowel movements
    
  • Hematochezia or melena (depending on briskness or location of diverticulum)
    
  • Peritonitis and septic shock (late complications)
    
• Cardiovascular:
  
  • Tachycardia (due to pain or blood loss)
    
  • Hypotension and shock (due to bleeding)
    

• May cause a variety of signs and symptoms:
  
  • <10% diagnosed preoperatively
    
  • Consider in patients with recurrent nonspecific abdominal pain, nausea and vomiting, or rectal bleeding.
    
• History and physical exam narrow diagnosis, but will not give specific findings for Meckel diverticulum.
  
• Rectal exam mandatory
  
• Nasogastric (NG) tube placement to rule out upper GI bleed
  

• CBC:
  
  • Decreased hematocrit due to bleeding
    
  • Rarely a cause of chronic anemia
    
  • Leukocytosis with diverticulitis, perforation, or gangrene
    
• Electrolytes, BUN, creatinine, coagulation studies
  
• Type and screen/cross-match when significant GI bleeding.
  

• CT abdomen/pelvis:
  
  • For suspected infection (appendicitis/diverticulitis) or bowel obstruction
    
• Abdominal radiographs:
  
  • Screening for bowel obstruction
    
  • Cannot diagnose Meckel diverticulum
    
• Tc-99m pertechnetate radioisotope scan (Meckel scan):
  
  • Noninvasive scan that identifies Meckel diverticulum containing heterotopic gastric mucosa
    
  • 90% accurate in children
    
  • 45% accurate in adults
    
• Small bowel enteroclysis:
  
  • 75% accuracy
    
  • Barium/methyl cellulose introduced through NG tube into distal duodenum or proximal jejunum
    
  • Increases the ability to detect Meckel diverticulum in adults
    
  • Diverticulum may be short and wide-mouthed, making diagnosis difficult.
    
• Barium enema:
  
  • Introduces fluid into distal small bowel
    
  • Look for diverticulum
    
• Angiogram for further evaluation of Meckel diverticulum if radioisotope scan and enteroclysis normal:
  
  • Blood supply is not always abnormal (vitelline artery).
    
• Ultrasound may be useful in nonbleeding presentations.
  
• Laparoscopic evaluation may provide both diagnosis and definitive treatment.
  
• ECG:
  
  • Eliminate myocardial ischemia as cause of abdominal pain.
    
• Colonoscopy:
  
  • Not useful in diagnosing Meckel diverticulum
    

• Adults:
  
  • Adhesions
    
  • Appendicitis
    
  • Arteriovenous malformation
    
  • Bowel obstruction
    
  • Diverticulitis
    
  • Hemorrhoids
    
  • Inflammatory bowel disease
    
  • Internal hernias
    
  • Intestinal polyps
    
  • Intussusception
    
  • Peptic ulcer disease
    
  • Pseudomembranous colitis
    
  • Volvulus
    
• Pediatric:
  
  • Adhesions
    
  • Anal fissures
    
  • Appendicitis
    
  • Atresia
    
  • Gastroenteritis
    
  • Hemolytic-uremic syndrome
    
  • Henoch–Schönlein purpura
    
  • Intestinal polyps
    
  • Intussusception
    
  • Malrotation
    
  • Milk allergy
    
  • Strictures
    
  • Volvulus
    

TREATMENT

Establish IV access for patients with rectal bleeding or abdominal pain.

• Stabilization followed by early surgical evaluation
  
• Hypotension:
  
  • Aggressive fluid resuscitation
    
  • Packed RBC (PRBC) transfusion with brisk rectal bleeding (more common in children)
    
  • Pressors for septic shock
    

• GI bleeding:
  
  • Fluid resuscitate and transfuse PRBC as indicated
    
  • Foley to follow urine output
    
  • NG tube to exclude brisk upper GI bleeding
    
  • Surgical consult for surgical intervention as indicated
    
• Obstruction:
  
  • NG tube
    
  • Foley
    
  • Surgical consult
    
• Diverticulitis/perforation:
  
  • NPO
    
  • Preoperative antibiotics
    
  • Surgical consult
    
• Surgical intervention:
  
  • Symptomatic Meckel diverticula should be resected
    
  • Asymptomatic Meckel diverticula discovered incidentally at laparotomy in children should be resected
    

• Ampicillin/sulbactam (Unasyn): 3 g (peds: 100–200 mg ampicillin/kg/24h) q8h IV
  
• Cefoxitin (Mefoxin): 1–2 g (peds: 100–160 mg/kg/24h) IV q6h
  
• Dopamine: 2–20 μ/kg/min IV
  

FOLLOW-UP

Presumptive diagnosis of Meckel diverticulum with diverticulitis, obstruction, intussusception, hemorrhage, or volvulus requires admission and surgical evaluation.

None

Postoperative surgical follow-up

• Painless, brisk, bright-red blood per rectum in an infant is often caused by Meckel diverticulum.
  
• Presents with a wide range of complications, including obstruction, intussusception, and hemorrhage.
  
• Often diagnosed in the OR for patients undergoing surgery for a presumptive appendicitis.
  
• Rule of 2’s:
  
  • 2% of the population
    
  • 2% risk of complications
    
  • Mostly <2 yr old
    
  • 2 in long
    
  • 2 ft from the ileocecal valve