Lecture 7: Small Intestine Pathology

Question 1

What is Meckel’s Diverticulum

Answer 1

Generally asymptomatic 2” small bowel out-pouching that occurs about 2 ft from the colon in 2% of the population, 2 types of tissues (gastric and pancreatic)

Question 2

Why would gastric tissue cause pain? How can you diagnose?

Answer 2

Can lead to peptic ulcer because it’s producing acid; Meckel’s scan

Question 3

EXTRINSIC obstruction causes…

Answer 3

Ischemia of small bowel

Question 4

Why must you compromise multiple vessels to create small bowel ischemia? How can this happen?

Answer 4

Lots of collaterals! Can happen when bowel itself is compressed

Question 5

Three examples of intestinal extrinsic obstruction

Answer 5

Strangulated hernia, volvulus, intussusception

Question 6

Stages of hernia

Answer 6

Reducible –> edema, lymph/venous compromise –> Incarcerated (non-reducible) –> arterial compromise –> Strangulated

Question 7

Risk factors for volvulus

Answer 7

Adhesions (surgery), poor motility, abnormal mesentery, congenital malrotation

Question 8

Describe intusseception

Answer 8

Leading point is mass lesion (tumor in adults, hyperplastic lymph tissue in children)

Question 9

Tx for adult intussception; tx for children intussception

Answer 9

Surgery; retrograde barium enema

Question 10

How common is celiac? How many symptomatic?

Answer 10

1:100; 20%

Question 11

What are HLA markers of celiac’s? Are they necessary or sufficient? What is another important marker?

Answer 11

HLA DQ2 or DQ8; necessary; circulating IgA anti-tissue transglutaminase (TGT)

Question 12

When do you measure IgA anti-tissue transglutaminase (TGT)?

Answer 12

At the point of diagnosis (must be eating gluten)

Question 13

Celiac’s disease have problems with what kinds of absorption?

Answer 13

Minerals/nutrients (proximal region most implicated)

Question 14

When can celiac’s strike?

Answer 14

Any age

Question 15

Sx of celiac’s?

Answer 15

Steatorrhea, failure to thrive, short stature, osteoporosis, anemia, infertility

Question 16

Histological finding of celiac disease (4)

Answer 16

Partial/total villous atrophy, intraepithelial lymphocytes, increased crypt mitoses, chronic inflammation (inflammatory cells)

Question 17

Three regions for lack of absorption in celiac’s

Answer 17

1. Attenuated glycocalyx (impaired digestion); 2. Attenuated microvilli (loss of SA); 3. Damaged organelles (impaired metabolism/absorption)

Question 18

Diseases associated with celiacs (5)

Answer 18

Ulcerative jejunoileitis, enteropathy-associated T cell lymphoma, GI and non-GI cancers, dermatitis herpetiformis, collagenous sprue

Question 19

Describe Whipple’s disease: define, cause, dx, tx

Answer 19

Mutlisystem disease caused by intracellular bacilli (Trophyrema whipplei) characterized by numerous foamy PAS+ macrophages; tx = PCR; rx = antibiotics

Question 20

Whipple’s disease fill what kind of cell?

Answer 20

Macrophages

Question 21

In the GI tract, Whipple’s disease causes…

Answer 21

Lymphatic obstruction

Question 22

Describe Congenital Lymphangeiectasia

Answer 22

Rare genetic disease associated with malformations of lymph system causing edema, chylous ascites (due to leaking of lymph fluid into abdominal cavity), and engorged lacteals leading to malnutrition, lymphcytopenia, and recurrent infections

Question 23

Small intestinal diverticulosis can cause what?

Answer 23

Bacterial overgrowth (due to stasis) leading to malabsorption

Question 24

Two types of diverticulosis

Answer 24

True (congenital) and false (out-pouching due to high pressures, more often occurs in elderly)