GI - Pathology (GI Diverticula, Intussuception, & volvulus) Flashcards
Pg. 355-356 in First Aid 2014 Sections include: -Diverticula of the GI tract -Zenker diverticulum -Meckel diverticulum -Intussusception and volvulus
What defines diverticulum?
Blind pouch protruding from the alimentary tract that communicates with the lumen of the gut
How do most diverticula arise, in what parts of the GI tract, and what kind of diverticula are they? Where do diverticula most often arise?
Most diverticula (esophagus, stomach, duodenum, colon) are acquired and are termed “false” in that they lack or have an attenuated muscularis externa. Most often in sigmoid colon.
What defines a “true” diverticulum? Give an example.
“True” diverticulum - all 3 gut wall layers outpouch (e.g., Meckel)
What defines a “false” diverticulum? What is another name for this? Where do these diverticula especially occur?
“False” diverticulum or Pseudodiverticulum - only mucosa and submucosa outpouch. Occur especially where vasa recta perforate muscularis externa.
What defines diverticulosis, and where is it commonly found?
Many false diverticula of the colon, commonly sigmoid
How common is diverticulosis, and in what age group does it frequently occur?
Common (in ~50% of people > 60 years)
What causes diverticulosis? With what behavior/condition is it associated?
Caused by increased intraluminal pressure and focal weakness in colonic wall. Assoicated with low-fiber diets.
How does diverticulosis often present? Of what symptom/sign is it a common cause?
Often asymptomatic or associated with vague discomfort. A common cause of hematochezia.
What are 2 complications of diverticulosis?
Complications include diverticulitis, fistulas.
What is diverticulitis, and what are 3 signs/symptoms classically associated with it?
Inflammation of diverticula classically causing LLQ pain, fever, leukocytosis.
What are 2 possible complications of diverticulitis? What may result from each?
(1) May perforate => peritonitis, abscess formation, or bowel stenosis (2) May also cause colovesical fistual (fistual with bladder) => pneumaturia
How is diverticulitis treated?
Give antibiotics
What stool finding(s) is (are) common in diverticulitis?
Stool occult blood is common +/- hematochezia
What is diverticulitis sometimes called with regard to its presentation, and why?
Sometimes called “left-sided appendicitis” due to overlapping clinical presentation
What kind of diverticulum is Zenker diverticulum?
Pharyngoesophageal false diverticulum.
What causes Zenker diverticulum, and where exactly does it occur?
Herniation of mucosal tissue at Killian triangle between the thyropharyngeal and cricopharyngeal parts of the inferior pharyngeal constrictor
What are 3 presenting symptoms of Zenker diverticulum?
Presenting symptoms: dysphagia, obstruction, foul breath from trapped food particles (halitosis).
In what patient population is Zenker diverticulum most common?
Most common in elderly males
What may Zenker diverticulum show on barium swallow?
Barium swallow shows contrast filling false diverticulum originating from posterior esophagus
What kind of diverticulum is Meckel diverticulum?
True diverticulum
What causes Meckel diverticulum? What may it contain?
Persistence of vitelline duct. May contain ectopic acid-secreting gastric mucosa and/or pancreatic tissue.
What is the most common congenital anomaly of the GI tract?
Meckel diverticulum
What are 5 signs/symptoms/results of Meckel diverticulum?
Can cause melana, RLQ pain, intussusception, volvulus, or obstruction near the terminal ileum
To what other abnormality of the vitelline duct can meckel diverticulum be contrasted, and what defines this other abnormality?
Contrast with omphalomesenteric cyst = cystic dilation of vitelline duct
How is Meckel diverticulum diagnosed?
Diagnosis: pertechnetate study for uptake by ectopic gastric mucosa
What is the mnemonic associated with Meckel diverticulum?
Think: “The FIVE 2’s: 2 inches long, 2 feet from the ileocecal valve, 2% of population, commonly presents in first 2 years of life, may have 2 types of epithelial (gastric/pancreatic).”
What is intussusception, and where does it commonly occur?
“Telescoping” of 1 bowel segment into distal segment, commonly at ileolcecal junction
How does intussusception often present, and what causes this?
Compromised blood supply => intermittent abdominal pain often with “currant jelly” stool
In what patient populations is intussusception unusual versus common? For each of these populations, with what is intussusception associated?
Unusual in adults (associated with intraluminal mass or tumor that acts as a lead point that is pulled into the lumen). Majority of cases occur in children (usually idiopathic; may be associated with recent enteric or respiratory viral infection).
How is the clinical approach to intussusception in children?
Abdominal emergency in early childhood
What is volvulus? What complications can it cause?
Twisting of portion of bowel around its mesentery; can lead to obstruction and infarction
Where in the GI tract can volvulus occur?
Can occur throughout the GI tract.
Which type of volvulus is more in common in infants and children versus the elderly?
Midgut volvulus more common in infants and children. Sigmoid volvulus more common in elderly.
