Clinical - GI and Liver

Question 1

How would cholangiocarcinoma present?

Answer 1

pain that looks a lot like acute cholecystitis (inflamed gallbladder) or acute cholelithiasis

Question 2

Pathologic finding associated w/ primary sclerosing cholangitis

Answer 2

onion-skinning

Question 3

AST normal values

Answer 3

8-20 U/L

Question 4

ALT normal values

Answer 4

8-20 U/L

Question 5

LDH normal values

Answer 5

45-90 U/L

Question 6

Name (3) measures for looking at liver synthetic fxn

Answer 6

• Albumin (3.5-5.5 g/dL)
• Prothrombin time (12-14 sec)
• Platelets (150,000 - 400,000)

Question 7

Total bilirubin (conj + undone) normal values

Answer 7

0.1 - 1.1 mg/dL

Question 8

Direct (conjugated) bilirubin

Answer 8

0.0 - 0.3 mg/dL

Question 9

Alkaline Phosphatase normal values

Answer 9

20-70 U/L

Question 10

GGT: what is it and what are normal values?

Answer 10

GGT = Gamma-glutamyl-transpeptidase. Enzyme that’s in hepatocytes and biliary epithelial cells.

Normal GGT = 0 - 30 U/L

Question 11

normal GGT with high Alk Phos is suggestive of? Why?

Answer 11

w/ normal GGT, it is unlikely liver origin that is the cause of the high Alk Phos (think of bone diseases or metastases).

However, high GGT + high Alk Phos = suggests liver origin

Question 12

Hemoglobin normal values for M and F

Answer 12

M: 13.5 - 17.5 g/dL

F: 12 - 16 g/dL

Question 13

Hematocrit normal values for M and F

Answer 13

M: 39 - 49%

F: 35 - 45%

Question 14

Creatinine normal values

Answer 14

0.6 - 1.2 mg/dL

Question 15

Which vitamin is Thiamine? Thiamine plays a MAJOR role in production of what?

Answer 15

Thiamine = B1

Plays a major role in production of Acetyl-CoA (energy metabolism and such)

Question 16

Wernicke-Korsakoff syndrome

Answer 16

Thiamine (B1) deficiency linked to alcoholism, causes neurological sx: confusion, memory problems, psychosis

Question 17

Which vitamin is Riboflavin?

Answer 17

Riboflavin = B2

Question 18

Which vitamin is Niacin? What is one unique property of Niacin?

Answer 18

Niacin = B3
Unusual for a vitamin, b/c Niacin can be made in small amounts in human body from Tryptophan. Low amounts of Trp in corn explain Niacin deficiencies in places where corn is dietary staple.

Question 19

Pellagra

Answer 19

Caused by Niacin (B3) deficiency:

Sx = 3 D’s: Diarrhea, Dermatits, and Dementia

Question 20

Which amino acid can be used as a precursor for niacin synthesis by the human body?

Answer 20

Tryptophan (Trp, W)

[endogenous synthesis of niacin is insufficient for health, but can help reduce amt needed from exogenous sources]

Question 21

Which vitamin is Biotin? What reaction does it catalyze?

Answer 21

Biotin = B7. ONLY used for carboxylation reactions. Include gluconeogenesis (co-enzyme to pyruvate carboxylase) and fatty acid synthesis (acetyl-CoA carboxylase)

Question 22

Multiple carboxylase deficiency: cause and sx

Answer 22

deficiency in either Biotinidase and/or Holocarboxylase synthase. These enzymes assist in making Biotin useable as a co-enzyme in carboxylation reactions.
Sx = alopecia, brittle fingernails, skin rashes, neuro deficits, and tingling of extremities.

Question 23

Which vitamin is Pantothenic acid? What are the (2) characteristic sx of pantothenic acid deficiency?

Answer 23

Pantothenic acid = B5

Deficiency sx: Numbness and painful burning/tingling of extremities

Question 24

Which vitamin is Pyridoxine? What is the co-enzyme form that all states must be converted into?

Answer 24

Pyridoxine = B6, which can be found in several states.

Co-enzyme form = Pyridoxal Phosphate

Question 25

All ____ enzymes use pyridoxal phosphate as a co-enzyme

Answer 25

transaminase enzymes

Question 26

Name (5) disorders that use pyridoxal phosphate as a co-enzyme and, thus, may respond to vitamin supplements

Answer 26

H-POX-H

• Homocysteinuria
• Pyridoxine-dependent epilepsy
• Ornithineaia with gyrate atrophy
• X-linked sideroblastic anemia
• Hypophosphatasia

Question 27

X-linked sideroblastic anemia: what’s the defect and what is the enzyme affected? Tx?

Answer 27

Defect in HEME synthesis!
Enzyme: delta-amino levulinic acid synthase
Tx: Vitamin B6 (Pyridoxal phosphate) supplement

Question 28

Homocysteinuria: what’s the defect and what enzyme is affected? Tx?

Answer 28

Defect in Methionine catabolism (breakdown)
Enzyme: Cystathionine synthase
Tx: Vitamin B6 (Pyridoxal phosphate) supplement

Question 29

Pyridoxine-dependent epilepsy: what job does the affected enzyme do. Tx?

Answer 29

Enzyme’s job is to break down Lysine in the brain.

Tx: Vitamin B6 (Pyridoxal phosphate) supplement

Question 30

What is Hypophosphatasia (mechanism and sx) and what is the tx?

Answer 30

general (non-tissue-specific) low Alkaline Phosphatase. Imp b/c it’s needed for pyridoxal entry into the BRAIN.
Sx = convulsions and epilepsy
Tx: Vitamin B6 (Pyridoxal phosphate) supplement

Question 31

the sideroblastic anemia caused by vitamin B6 deficiency is caused by a reduction in ___

Answer 31

the synthesis of heme

Question 32

important complication of decompensated cirrhosis with ascites

Answer 32

spontaneous bacterial peritonitis
(b/c ascites is from the portal HTN; when fluid is just sitting there, can be pushed out into peritoneum and can be nutrient-rich environment for bacterial infection)

Question 33

Which inflammatory bowel disease is more likely associated with fat-soluble vitamin deficiencies? Which vitamins are these?

Answer 33

Crohn’s disease - usually involves the terminal ileum, which absorbs the fat-soluble vitamins = A, D, K, and E

Question 34

Name (4) extraintestinal manifestations of BOTH inflammatory bowel diseases

Answer 34

BOTH Crohn’s and Ulcerative Colitis (A-E-O-R)

• Arthritis = Peripheral or Spondylitis
• Eye inflammatory = Uveitis, Episcleritis
• Oral ulcerations = Apthous Stomatitis
• Rash = Pyoderma Gangrenous, Erythema Nodosum

Question 35

Rovsing sign

Answer 35

sign of acute appendicitis, where pressure on LLQ causes pain in RLQ
(think the pain roves to the right)

Question 36

mechanism of how vitamin B6 deficiency causes sideroblastic anemia

Answer 36

Pyridoxal phosphate (B6) is an essential co-enzyme for delta-amino-levulinic acid synthase, which catalyzes the first step in heme synthesis. So reduction in heme leaves the Fe nowhere to go. So it deposits around nuclei = sideroblasts

Question 37

What type of anemia is caused by folate deficiency? By what mechanism?

Answer 37

Folate (B9) deficiency causes megaloblastic anemia due to the need for nucleotides in rapid proliferation of RBCs. So cells continue to grow, but division is delayed b/c replication has slowed.

Question 38

Folate v. Folic acid

Answer 38

Folic Acid = the specific form used to fortify foodstuffs (which is readily absorbed by our GI tract b/c it’s monoglutanimated)
v.
Folate = the other polyglutaminated forms of Vitamin B9 found in natural products that are less well absorbed

Question 39

Which vitamin is Cobalamin? Where is it almost exclusively found?

Answer 39

Vitamin B12. Found almost entirely in animal products (so vegans need fortified foods or supplements)

Question 40

What is the folate trap?

Answer 40

When folic acid supplementation masks a Vitamin B12 deficiency

Question 41

mechanism of pernicious anemia. Tx?

Answer 41

autoimmune destruction of parietal cells, which synthesize Intrinsic Factor needed for B12 absorption in the ileum.
Tx = B12 injections

Question 42

Name (2) drugs interactions that can decrease vitamin B12 absorption

Answer 42

1) PPIs (Omeprazole): reduce stomach acid. Prolonged use necessary for B12 deficiency to develop
2) Tetracyclin - can interfere w/ B12 absorption. So if you’re taking B12 supplements, must take them at diff times than the abx

Question 43

Why would a person w/ defective induction of hepcidin be discouraged from taking Vitamin C supplements?

Answer 43

Hemochromatosis is caused by a defect in hepcidin induction, leading to iron overload. Vit C supplements will even further increase iron absorption, increasing the pt’s risk for organ damage