GI motility disorders

Question 1

histopathology of achalasia

Answer 1

degeneration of myenteric NO (inhibitory) neurons due to inflammation

Question 2

what can mimic GI dysmotility both radiographically and manometrically

Answer 2

mechanical obstruction (must rule out!)

Question 3

three main causes of secondary achalasia

Answer 3

psuedoachalasia (Cancer associated), post fundoplication, Chagas

Question 4

Diabetic gastroparesis: what type of neuropathy? What happens?

Answer 4

autonomic (vagal). Gastric body and antral hypomotility and pylorospasm result in prolongation of emptying times

Question 5

two motility patterns of small bowel and describe them

Answer 5

Fed pattern- segmenation. Fasting pattern- MMC

Question 6

three phases of MMC

Answer 6

Phase 1- motor inactivity. Phase 2- intermittent, non propagating contractions. Phase 3- burst of contractions from duodenum to distal ileum

Question 7

Scleroderma: what type of neuropathy? Where in GI tract? Most common location? What happens when it occurs in small bowel?

Answer 7

myopathic. Any part. Esophageal dysmotility. Absent contractile activity leads to dilation with stacked coin appearance and diverticulae

Question 8

two main causes of intestinal pseudo-obstruction

Answer 8

post operative ileus. Scleroderma

Question 9

Ogilvie’s Syndrome: what type of neuropathy? when does it occur? Where does it occur? What happens?

Answer 9

autonomic. post-op. hindgut. Colonic distention in absence of mechanical obstruction

Question 10

Hirschsprung’s Disease: how do you get it? what happens? what results?

Answer 10

congenital, failure of neural crest cells giving rise to ENS (esp NO containing neurons) to populate distal digestive tract. Internal anal sphincter won’t relax. megacolon