Heme, Iron, Blood Plasma

Question 1

Name 2 types of congenital methemoglobinemia

Answer 1

Congenital - lack of NADH cyctochrome b5

Inherited hemoglobin M disease - mutation in heme pocket which stablizes ferric F3 iron.

Question 2

Causes of acquired methemoglobinemia

Answer 2

Sulfa drugs (TMP), lidocaine, benzocaine, Dapsone

Question 3

Treatment methemoglobinemia

Answer 3

reducing agents - methylene blue or ascorbic acid

Question 4

Explain the Bohr effect

Answer 4

Increase in pH (decrease in CO2) hemoglobin affinity increases

Question 5

An increase in temperature does what to hemoglobin’s oxygen binding affinity?

Answer 5

Decreases it

Question 6

What is the role of bicarbonate in the transport of oxygen and CO2 between the lungs and tissues?

Answer 6

Tissues - CO2 converted to bicarb and H+ the H+ then binds the heme and release O2 to tissues
Lungs - H+ released from hemeglobin to bind to O2 - the H+ binds bicarbonate forming water and CO2 which is expired.

Question 7

Most common deficiency in hereditery spherycytosis?

Answer 7

ankyrin

Question 8

Symptoms of spheryocytosis?

Answer 8

splenomegaly, jaundice, secondary to hemolytic anemia. typically follows EBV or intense physical work

Question 9

Treatment for spherocytosis?

Answer 9

1. Give vaccines for HIB, PCV, meningcocal
2. Remove spleen
3. Folic acid supplement

Question 10

Difference between oncotic and hydrostatic pressure?

Answer 10

Hydrostatic pressure created by beating of the heart

Oncotic pressure is based on the amount of proteins in the blood

Question 11

List causes of ascites

Answer 11

Alcoholism (cirrhois), CHF, Kwashiorkor (lack of proteins)

Also some cancers where the tumors produce fluid

Question 12

Treatment for Ascites

Answer 12

Periscentesis - give albumin if remove more than 5 L

Question 13

What is genetic heredibility of G6PD

Answer 13

x-linked

Question 14

If you have G6PD you are unable to reduce this cofactor

Answer 14

NADP+ to NADPH

Question 15

List stressers of G6PD and what do they cause

Answer 15

Infection, Fava beans, drugs like antimalarials, Dapsone, and sulfa, Henna tattoos. Oxidative stress

Question 16

Histologic findings for G6PD

Answer 16

Heinz bodies, bite cells and blister cells

Question 17

Sx of G6PD

Answer 17

Dark urine, skin pallor, jaundice, hepatosplenamegaly, fever

Question 18

What cofactor is required for Glutathione reductase to make glutathione

Answer 18

FAD

Question 19

What pathway does G-PD enter into?

Answer 19

Pentose Phosphate Pathway

Question 20

Why is selenium required in diet?

Answer 20

Allows conversion of H202 to H+ and H20

Question 21

What type of anemia is associated with lead poisoning?

Answer 21

microcytic anemia

Question 22

What enzymes does Pb2+ block in the heme synthesis pathway?

Answer 22

Delta- ALA - dehydratase and ferrochetalase

Question 23

What is porphyria?

Answer 23

Inherited disorder of heme production

Question 24

Name symptoms of acute porphyria

Answer 24

constipation, diarrhea, n/v, back, chest and neck pain, AMS, tachycardia

Question 25

Diagnostic signs of acute porphyria

Answer 25

Increase in intermediates (porphobilinogen), increased ALA if lead poisoning

Question 26

What defect in heme synthesis pathway is not a porphyria?

Answer 26

delta -ALA synthase deficiency (also Autosomal recessive)

Question 27

Describe Cutena Tarda.

Answer 27

Hepatic URO-D deficiency, linked to Hep-C (acquired) - congenital is HFE C282Y homozygous

Question 28

Symptoms of cutaneous porphyria

Answer 28

Deposits in the skin, scarring, hyperpigmention, hyper trichosis, bullous dermatosis

Question 29

B6 deficiency manifests as this.

Answer 29

Microcytic hypochromatic anemia

Question 30

What supplement is needed for a patient on Isoniazid?

Answer 30

B6 - pyridoxal phosphate

Question 31

What populations are at high risk for B6 deficiency?

Answer 31

Pregnant people, alcoholics, diabetes, HIV+, seizure disorders

Question 32

If a pt. presents with excess unconjugated bilirubin there is a problem with this reaction?

Answer 32

Glucorination in the liver

Question 33

Bilirubin is converted to this form for excretion in the urine, stool

Answer 33

Urobilinogens, stercobilinogens

Question 34

List significant lab findings for hemochromatosis

Answer 34

Increased serum Fe, ferritin, transferrin iron sat. | Decreased total iron binding capacity

Question 35

List significant lab finding for iron deficiency anemia

Answer 35

Increased total iron binding capacity. | Decreased serum iron, ferritin and transferrin iron

Question 36

What AOCD?

Answer 36

Anemia of chronic disease - too much stored iron, can't access it.

Question 37

Confirmation of hemochromatosis diagnosiss is done with these procedures/tests

Answer 37

Liver biopsy and T2star MRI

Question 38

What is the mutation associated with Type I hereditary hemochromatosis?

Answer 38

Cysteine to Tyrosine substitution at 282, C282Y

Question 39

Effect of C282Y mutation

Answer 39

Decreased hepciden and increased iron absorption

Question 40

Triad of symptoms for hemachromatosis or iron overload

Answer 40

Diabetes, hepatomegaly, hyperpigmentation, leads to cirrhois, hepatocellular carcinoma and CHF

Question 41

Treatment for hemochromatosis

Answer 41

Ferritin < 1000 mg/L - phelbotomy | Ferritin > 1000 mg/L - add liver biopsy - check for HCC

Question 42

Causes of iron deficiency anemia

Answer 42

Blood loss, increased requirement, and decreased absorption

Question 43

Symptoms of iron deficency anemia

Answer 43

Fatigue, irritability, pica, koilonychia (spooned nails), glossitis. kids - impaired psychomotor development

Question 44

Treatment of iron deficency includes in this steps

Answer 44

Look for source of blood loss, rule out intervascular hemolysis. If negative supplement with Iron

Question 45

Disease states associated with AOCD

Answer 45

Infectious - TB, Malignant - Hodgkins, NHL, Autoimmune - RA, trauma and heart disease

Question 46

Release of what 2 immunologic factors results in increased hepcidin

Answer 46

IL6 and IL1B

Question 47

Treatment of AOCD

Answer 47

Treat the underlying process and give EPO

Question 48

Why is heme iron absorbed more readily than non-heme iron

Answer 48

Heme does not have to converted to be absorbed.

Question 49

List 2 transporters for heme

Answer 49

Ferrous +2 - HPC1 | (Ferric +3 converted to Ferrous) - DMT1

Question 50

What enzyme converts ferric iron to ferrous iron?

Answer 50

Duodoenal cytochrome B reductase

Question 51

List promotors of iron absorption

Answer 51

Ascorbic acid, citric acid, beta carotene, alcohol

Question 52

Describe Sprue

Answer 52

Disorder of duodenum which inhibits absoprtion of iron (often called Celiac)