Heme, Iron, Blood Plasma Flashcards Preview

IHO Final > Heme, Iron, Blood Plasma > Flashcards

Flashcards in Heme, Iron, Blood Plasma Deck (52):
1

Name 2 types of congenital methemoglobinemia

Congenital - lack of NADH cyctochrome b5
Inherited hemoglobin M disease - mutation in heme pocket which stablizes ferric F3 iron.

2

Causes of acquired methemoglobinemia

Sulfa drugs (TMP), lidocaine, benzocaine, Dapsone

3

Treatment methemoglobinemia

reducing agents - methylene blue or ascorbic acid

4

Explain the Bohr effect

Increase in pH (decrease in CO2) hemoglobin affinity increases

5

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

Decreases it

6

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

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.

7

Most common deficiency in hereditery spherycytosis?

ankyrin

8

Symptoms of spheryocytosis?

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

9

Treatment for spherocytosis?

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

10

Difference between oncotic and hydrostatic pressure?

Hydrostatic pressure created by beating of the heart
Oncotic pressure is based on the amount of proteins in the blood

11

List causes of ascites

Alcoholism (cirrhois), CHF, Kwashiorkor (lack of proteins)
Also some cancers where the tumors produce fluid

12

Treatment for Ascites

Periscentesis - give albumin if remove more than 5 L

13

What is genetic heredibility of G6PD

x-linked

14

If you have G6PD you are unable to reduce this cofactor

NADP+ to NADPH

15

List stressers of G6PD and what do they cause

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

16

Histologic findings for G6PD

Heinz bodies, bite cells and blister cells

17

Sx of G6PD

Dark urine, skin pallor, jaundice, hepatosplenamegaly, fever

18

What cofactor is required for Glutathione reductase to make glutathione

FAD

19

What pathway does G-PD enter into?

Pentose Phosphate Pathway

20

Why is selenium required in diet?

Allows conversion of H202 to H+ and H20

21

What type of anemia is associated with lead poisoning?

microcytic anemia

22

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

Delta- ALA - dehydratase and ferrochetalase

23

What is porphyria?

Inherited disorder of heme production

24

Name symptoms of acute porphyria

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

25

Diagnostic signs of acute porphyria

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

26

What defect in heme synthesis pathway is not a porphyria?

delta -ALA synthase deficiency (also Autosomal recessive)

27

Describe Cutena Tarda.

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

28

Symptoms of cutaneous porphyria

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

29

B6 deficiency manifests as this.

Microcytic hypochromatic anemia

30

What supplement is needed for a patient on Isoniazid?

B6 - pyridoxal phosphate

31

What populations are at high risk for B6 deficiency?

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

32

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

Glucorination in the liver

33

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

Urobilinogens, stercobilinogens

34

List significant lab findings for hemochromatosis

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

35

List significant lab finding for iron deficiency anemia

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

36

What AOCD?

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

37

Confirmation of hemochromatosis diagnosiss is done with these procedures/tests

Liver biopsy and T2star MRI

38

What is the mutation associated with Type I hereditary hemochromatosis?

Cysteine to Tyrosine substitution at 282, C282Y

39

Effect of C282Y mutation

Decreased hepciden and increased iron absorption

40

Triad of symptoms for hemachromatosis or iron overload

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

41

Treatment for hemochromatosis

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

42

Causes of iron deficiency anemia

Blood loss, increased requirement, and decreased absorption

43

Symptoms of iron deficency anemia

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

44

Treatment of iron deficency includes in this steps

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

45

Disease states associated with AOCD

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

46

Release of what 2 immunologic factors results in increased hepcidin

IL6 and IL1B

47

Treatment of AOCD

Treat the underlying process and give EPO

48

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

Heme does not have to converted to be absorbed.

49

List 2 transporters for heme

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

50

What enzyme converts ferric iron to ferrous iron?

Duodoenal cytochrome B reductase

51

List promotors of iron absorption

Ascorbic acid, citric acid, beta carotene, alcohol

52

Describe Sprue

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