Malabsorption- Clinical and Path

Question 1

Malabsorption may be generalized or it may be a very specific type of malabosorption. Pay especially close attention to fat because the absorption of fat is very complex.

Answer 1

ok

Question 2

Steattorhea definition

Answer 2

Greater than 5% of dietary fat in stool

Question 3

Whom to suspect of having steatorrhea?

Answer 3

• weight loss
• stool characteristic
• osteomalacia– vitamin D is fat soluble vitamin
• Easy bruising- vitamin K (ADEK)
• iron deficiency anemia not due to blood loss
• Adult development of lactase insufficiency
• Gastric surgery- billroth II…take out the antrum of the stomach where gastrin is produced which leads to less acid.

Question 4

Steattorhea stool characteristic

Answer 4

floats
greasy
stinks
oil droplets
hard to flush

Question 5

Mechanisms causing diarrhea in steattorhea?

Answer 5

• More osmotically active substances in the GI lumen from malabsorption pulls out water.
• Hydroxylation of 10- hydroxy oleate acts as a cathartic ( something that speeds up defecation)
• Fatty Acids themselves impair fluid and electrolyte absorption

Question 6

What is chemical fat balance?

Answer 6

How much fat you are eating and how much fat you have in your stool

Question 7

What is D-xylose

Answer 7

Xylose is a pentose sugar that doesn’t require dgestion to be absorbed, very unique. D-xylose test allows you to differentiate between a digestion problem and an absorption problem. If someone has a digestion problem, they should still absorb D-Xylose without any trouble. If there is an absorption problem, they will not

Question 8

Secretin test?

Answer 8

Most sensitive test for pancreatitis. Give secretin which stimulates bicarb production by the pancreas and then measure bicard secretion. if the pancreas is injured, no bicarb. Very hard to do.

Question 9

x-ray

Answer 9

with all of these tests you are looking to see whether it is a digestion problem or an absorption problem. Chronic pancreatitis will often show calcifications on x-ray.

Question 10

Hydrogen breath test?

Answer 10

Carbohydrate malabsorption. If carbs are not absorbed, bacteria will ferment the carbs and release Hydrogen

Question 11

What causes the most steatthorea?

Answer 11

Pancreatic insufficiency

Question 12

What is zollinger-Ellison

Answer 12

Gastrin producing tumor…tons of acid….this acid gets in the small intestine and prevents the pancreatic enzymes from working and thus you get malabsorption

Question 13

Conditions that can cause bile acid insufficiency will cause steattorhea. SOme examples are

Answer 13

• Cholestatic liver disease
• Terminal Illuem resection- no reabsorption of bile acid.
• Bacterial overgrowth in small intestine- conjugates bile acid and prevents it from working correctly
• Reduced CCK release-

Question 14

Issues with intestinal stage absorption deal with epithelial cell surface digestion

Answer 14

ok

Question 15

Remember that problems with lymphatic transport will also impede fat absorption

Answer 15

ok

Question 16

Characteristic pathologic finding of malabsorption

Answer 16

Villous Blunting

Question 17

Intraepithelial lymphocytes (CD-8)

Answer 17

Celiac disease

Question 18

Viral gastroenteritis can cause a temporary disacharidase (lactase) deficiency which can present as diarrhea upon ingestion of milk for a few days after the infection has cleared

Answer 18

ok

Question 19

Infection in intestines, mesenteric lymph nodes, brain, heart, and joints?

Answer 19

Whipple Disease

LICCJ
Lymph nodes
Intestines
Cerebral
Cardiac
Joints

Question 20

WHipple disease causative organism is

Answer 20

Tropheryma WHippelii

Question 21

Genetic predisposition to Celiac Disease?

Answer 21

95% have HLA- DQ2

Question 22

What causes the most steatorrhea?

Answer 22

Pancreatic Insufficiency (loss of pancreatic lipase)

Question 23

Intraluminal causes of malabsorption

Answer 23

• Chronic Pancreatitis
• Zollinger Ellison Gastrinoma
• Post Gastrectomy
• Cystic Fibrosis
• Also Bile Acid insufficiency (bile acids necessary for fat absorption) Things that can cause bile acid insufficiency= Cholestatic Liver disease, Terminal Illeum resection, Bacterial overgrowth in the small intestine (these little fuckers conjugate the bile acids and make them inactive, reduced CCK release means less bile released from gall bladder.)

Question 24

Causes of malabsorption in GSE?

Answer 24

• Cells at the surface of intestine are immature
• Intestine is in a secretiry state
• Concentration of bile salts is reduced
• The abosrptive functions of mature enterocytes is reduced
• Complex lipid synthesis is reduced
• The endocrine cells that make CCK are reduced
• The absorptive area of the intestineis greatly reduced

Question 25

What kind of antibody test is most helpful in GSE determination

Answer 25

IgA High sensitivity and specificity

Question 26

Main manifestation of malabsorption=

Answer 26

Steatorrhea…this is the easiest to see, doesn’t mean that fat is the only thing being screwed with