GI Basics

Question 1

_________ and __________ assist in the chemical breakdown of food.

Answer 1

1. Hydrochloric acid- secreted by parietal cells

2. Pepsin- pepsinogen secreted by chief cells (for protein digestion)

Question 2

What 3 hormones stimulate parietal cells?

Answer 2

1. Gastrin- stimulates stomach acid secretion and motility
2. Histamine- stimulates parietal cells to secrete HCl
3. Acetylcholine- directly stimulates parietal cells to secrete HCl

Question 3

________ produced by pancreatic delta (D cells) acts as negative feedback, inhibiting the secretion of gastrin, insulin, glucagon, and pancreatic enzymes

Answer 3

Somatostatin

Question 4

_____ is the main cause of Thiamine (B1) deficiency in the US.

Answer 4

ETOH

Question 5

_____ is associated with B1 deficiency and can be classified as “wet” or “dry.”

Answer 5

Beriberi.

Wet- high output heart failure, dilated cardiomyopathy

Dry- nervous system changes

Question 6

_____ is associated with B1 deficiency and has an “AGO” triad which includes: Ataxia, Global confusion, and Ophthalmoplegia.

Answer 6

Wernicke’s Encephalopathy

Question 7

_____ is associated with B1 deficiency and results in memory loss (esp. short term), confabulation. It is irreversible.

Answer 7

Korsakoff’s Dementia

Question 8

Oral-Ocular-Genital Syndrome is associated with ____ deficiency.

Answer 8

B2 (Riboflavin)

Oral- magenta colored tongue, angular cheilitis

Ocular- photophobia and corneal lesions

Genital- scrotal dermatitis

Question 9

B3 deficiency (Niacin/Nicotinic acid) can cause Pellagra which is associated with “3 D’s.” These are:

Answer 9

Diarrhea, Dementia, Dermatitis

Question 10

Animal foods are the primary natural source of B12. Stomach acids release B12 from food & binds it to intrinsic factor for later absorption in the TERMINAL ILEUM

Answer 10

FYI

Question 11

Some etiologies of B12 deficiency include:

Answer 11

1. Pernicious anemia- autoimmune destruction/loss of gastric parietal cells that secrete intrinsic factor. Dx- Ab testing, SCHILLING TEST.
2. Strict vegans- lack of animal sources in the diet if B12 not supplemented.
3. Malabsorption- ETOHism, diseases affecting the ileum (Celiac, Crohn)
4. Decrease in intrinsic factor production- acid-reducing drugs (H2RA & PPIs), gastric bypass

Question 12

What are some clinical manifestations of B12 deficiency?

Answer 12

Neurologic symptoms- paresthesias, gait abnormalities, memory loss, dementia.

GI- anorexia, diarrhea, glossitis