GI

Question 1

Parietal cells are oxyntic (pale pink) cells found in which layer of the gastric body and fundus?

Answer 1

Upper glandular layer

Question 2

Which 2 amphipathic molecules help make small amounts of cholesterol soluble for secretion in bile?

Answer 2

Bile salts and Phosphatidylcholine (a phospholipid)

Question 3

Which 2 regulatory mechanisms exist for inactivating/regulating trypsin?

Answer 3

• SPINK1 is secreted by pancreatic acinar cells = trypsin inhibitor
• Trypsin is its own activator and inhibitor

Question 4

Systemic mastocytosis is often associated with mutations in what?

Answer 4

KIT receptor tyrosine kinase

Question 5

The enteric bacteria responsible for small intestinal bacterial overgrowth can produce which vitamins?

Answer 5

Vitamin K and Folate

Question 6

When an ulcer penetrates the posterior duodenal wall, it is likely to erode into which artery?

Answer 6

Gastroduodenal

Question 7

At birth, an infant with significant drooling + choking, coughing, and cyanosis with feeds should raise suspicion for what?

Answer 7

Tracheoesophageal fistula w/ esophageal atresia

Question 8

Strictures as a complication of Chron Disease occur as a result of what?

Answer 8

• Bowel wall edema, fibrosis, and hypertrophy (thickening) of the muscularis mucosae
• Can lead to small bowel obstruction

Question 9

What is the optimal site of biopsy for suspected H. pylori?

Answer 9

Gastric antrum

Question 10

What is the site of protrusion of indirect inguinal hernias?

Answer 10

The deep (internal) inguinal ring = opening in transversalis fascia

Question 11

What are the characteristic lab findings and intestinal biopsy findings of pt with Abetalipoproteinemia?

Answer 11

• Labs: very LOW plasma TAG’s and cholesterol; chylomicrons, VLDLs, and apoB are absent from the blood
• Biopsy: normal intestinal mucosal architecture, but enterocytes contain clear or foamy cytoplasm, prominent at the tips of the villi

Question 12

What are Councilman vs. Mallory bodies; what is each associated with?

Answer 12

• Councilman: hepatocytes which have undergone apoptosis and appear round, acidophilic (pink on H&E stain); seen in viral hepatitis
• Mallory: are damaged cytokeratin filaments within hepatocytes that usually arise in pt’s with alcoholism