Pathology of the GI Tract- SI and Colon (1)

Question 1

what are the layers of the GI tract?

Answer 1

mucosa, submucosa, muscularis, and serosa

Question 2

what are the components of the mucosa of the GI tract?

Answer 2

epithelium, lamina propria, and a thin smooth muscle layer called the muscularis mucosa

Question 3

the presence of congenital GI disorders should prompt what?

Answer 3

evaluation of other organs because many organs develop simultaneously during this same time frame

Question 4

what is a common congenital anomaly that is commonly associated with other congenital malformations, particularly cardiac defects?

Answer 4

Tracheoesophageal (TE) fistula

Question 5

what is another congenital malformation that is related to a TE fistula?

Answer 5

esophageal atresia

Question 6

what is the most common form of a TE fistula?

Answer 6

EA with a distal TE fistula

Question 7

why do TE fistulas occur?

Answer 7

due to abnormal septation of the caudal foregut during the 4th and 5th weeks of embryonic development

Question 8

what is Meckel diverticulum?

Answer 8

failed involution of the vitelline duct

Question 9

what is the vitelline duct?

Answer 9

it connects the lumen of the developing gut to the yolk sac

Question 10

how can you remember the characteristics of Meckel diverticulum?

Answer 10

the rule of 2’s

Question 11

what are some complications associated with Meckel diverticulum?

Answer 11

the mucosal lining of meckel diverticula could be ectopic pancreatic or gastric tissue; the ectopic gastric tissue could secrete acid causing peptic ulceration of adjacent small intestinal mucosa

Question 12

who is more likely to have pyloric stenosis?

Answer 12

male»females; monozygotic twins»dizygotic twins; increased risk in 45, XO and Trisomy 18

Question 13

what is pyloric stenosis associated with?

Answer 13

use of antibiotics: arythromycin and azithromycin in the mom during pregnancy

Question 14

how does pyloric stenosis present?

Answer 14

generally between the 3rd and 6th weeks of life as new onset regurgitation, projectile nonbilious vomiting after feeding, and frequent demands for refeeding

Question 15

what is occurring anatomically in cases of pyloric stenosis?

Answer 15

the gastric outflow tract is obstructed by hyperplasia of the pyloric muscularis propria

Question 16

what is Hirschspring disease?

Answer 16

aka aganglionic megacolon; there is abnormal migration or premature death of enteric ganglion cells

Question 17

what may Hirschspring disease occur in combination with?

Answer 17

other developmental abnormalities such as down syndrome and serious neurologic abnormalities

Question 18

how does hirschspring disease present?

Answer 18

with functional obstruction and the rectum is always involved

Question 19

intrinsic innervation of much of the GI tract is provided by the enteric nervous system; these enteric neurons are grouped into two plexuses, what are they?

Answer 19

the myenteric plexus (plexus of Auerbach) and the submucosal plexus (plexus of Meissner)

Question 20

which plexus is responsible for motility, especially the rhythm and force of the contraction of the muscularis?

Answer 20

myenteric plexus (plexus of Auerbach)

Question 21

which plexus is responsible for regulating digestive secretions and reacting to the presence of food?

Answer 21

the submucosal plexus (plexus of Meissner)