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Flashcards in GIT: Small Intestine Deck (25)
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Meckel diverticulum is caused by incomplete _____

Meckel diverticulum is caused by incomplete involution of vitelline duct


describe how Meckel diverticulum is an example of heterotopia

Meckel diverticulum contains gastric mucosa and pancreatic tissue


describe complications of Meckel diverticulum

  • complications:
    • hemorrhage and peptic ulcer
    • intestinal obstruction
    • diverticulitis
    • perforation
    • fistula


describe intestinal changes that occur in celiac sprue

  • typical: villous atrophy (reduced area for absorption)
  • increased intraepithelial lymphocytes
  • elongated and hyperplastic crypts
  • increased lymphocytes, macrophages, plasma cells in lamina propria


describe the pathogenesis of celiac sprue


describe the image 


describe serologic tests done in celiac sprue

  • serologic tests:
    • anti-gliadin and anti-endomysial antibodies
    • anti-tissue transglutaminase (tTG) antibodies


name the HLA genotypes associated with celiac sprue

HLA-DQ2 (majority) and HLA-DQ8


in patients with celiac sprue, there is a long-term risk of ____

in patients with celiac sprue, there is a long-term risk of intestinal T-cell lymphomas


describe tropical sprue (post-infectious sprue)

  • pathogenesis related to bacterial infection superimposed on pre-existing small intestine injury
  • as opposed to celiac sprue, all parts of small intestine equally involved
  • responds to antibiotics


as opposed to celiac sprue, in tropical sprue, ____

as opposed to celiac sprue, in tropical sprue,  all parts of small intestine are equally involved


describe Whipple disease

  • mainly involves intestine, joints and CNS
  • G+ve sickle-shaped bacteria
  • mucosa laden with distended macrophages in lamina propria; contain PAS positive granules
  • may have granulomatous inflammation
  • treated with antibiotics


Whipple disease is caused by _____

Whipple disease is caused by G+ve sickle-shaped bacteria (Tropheryma whippelii)


describe the image

Whipple disease


describe Giardia

  • protozoan gut pathogen with flagellum
    • trophozoites and cysts are shed
  • usually acquired from drinking water contaminated with cysts
    • poor sanitation and crowded living conditions predispose to infection
  • immunosuppression increases risk


describe predisposing factors for luminal obstruction

  • predisposing factors:
    • false teeth
    • gastrectomy
    • intestinal adhesions
    • inadequate mastication and large amounts of food


list therapeutic agents that can lead to luminal obstruction

barium sulphate and antacid gels


___, or ingested hairs, can cause luminal obstruction

bezoars, or ingested hairs, can cause luminal obstruction


roundworms, such as _____, can cause luminal obstruction

roundworms, such as Ascaris lumbricoides, can cause luminal obstruction


list 2 endogenous origins of luminal obstruction

  • meconium ileus in infants with CF
    • thick mucus at mid-terminal ileum
  • gallstone ileus
    • usually a stone >2.5 cm in diameter lodges in terminal ileum
    • usually through cholecystoduodenal fistula
    • rarely small stone grows in biliary tree


list the 3 conditions of the small intestine that lead to ischemia

  • volvulus
  • strangulated hernia
  • gangrene


describe acute appendicitis

  • inflammation of the appendix
  • underlying obstruction of the lumen in 50-80% of cases


list the complications of acute appendicitis

  • complications:
    • perforation 
    • peritonitis
    • periappendiceal abscess
    • liver abscess
    • bacteremia


describe an adenoma, a low-grade appendiceal mucinous neoplasm (LAMN), and a mucinous adenocarcinoma

  • adenoma:
    • confined to lumen, wall normal
  • LAMN: 
    • mucin, epithelium in wall; non-destructive
    • can metastasize to ovary and peritoneum
  • mucinous adenocarcinoma:
    • high-grade, destructive invasion


describe a pseduomyxoma peritonei

  • peritoneal involvement by mucinous implants
  • most: appendix
  • low-grade tumors (LAMN)
    • abundant mucin
    • scant low-grade neoplastic epithelium
  • high-grade tumors (mucinous adenocarcinoma)
    • abundant malignant epithelial cells
    • signet ring cells can be present