Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2nd U2 Path > Macrocytic anemia > Flashcards

Macrocytic anemia Flashcards

1
Q

Anemia with an MCV > 100um3…

A

Macrocytic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 2 most common causes of macrocytic anemia?

A

Folate deficiency

Vitamin B12 deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What must be removed from serum methyltetrahydrofolate (THF) in order for it to participate in DNA synthesis?

A

Methyl group must be transferred to Vitamin B12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is the methy group transferred to from methyltetrahydrofolate to allow THF to participate in DNA synthesis?

A

Vitamin B12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where does Vitamin B12 transfer the methyl group to produce methionine?

A

Homocysteine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What leads to megaloblastic anemia?

A

Impaired division and enlargement of RBC precursors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Hypersegmented neutrophils occur with macrocytic anemia. What causes there to be produced?

A

Impaired division of granulocytic precursors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are some causes of macrocytic anemia without megaloblastic change?

A

Alcoholism
Liver disease
Drugs (5-FU)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does the absorption of folate occur?

A

Jejunum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are some common causes of folate deficiency?

A

Poor diet
Increased demand
Folate antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Macrocytic anemia can be caused by a poor diet. Who are the two most common groups of people who present with a folate deficiency due to poor diet?

A

Alcoholics

Elderly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are some causes of increased demand for folate, causing a folate deficiency?

A

Pregnancy
Cancer
Hemolytic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a common drug that is a folate antagonist causing a folate deficiency?

A

Methotrexate—inhibits dihydrofolate reductase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What changes are seen with RBCs with folate deficiency?

A

Macrocytic RBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What changes are seen with neutrophils with folate deficiency?

A

Hypersegmented neutrophils (> 5 lobes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

With respect to folate levels and serum homocysteine, what are the laboratory values seen with a folate deficiency?

A

Serum folate—decreased

Homocystein—increased

17
Q

What is a normal finding seen with folate deficiency with helps differentiated it from a different cause macrocytic anemia?

A

Methylmalonic acid

18
Q

What is bound to vitamin B12 to allow it to be carried to through the stomach?

A

R-binder

19
Q

What cause the detachment of R-binder from vitamin B12?

A

Pancreatic proteases

20
Q

Where does the detachment of R-binder from vitamin B12 occur?

A

Duodenum

21
Q

What binds vitamin B12 in the small bowel allowing absorption of B12 by the ileum?

A

Intrinsic factor

22
Q

What cells produce intrinsic factor, which binds vitamin B12 to allow absorption in the ileum?

A

Gastric parietal cells

23
Q

What is the most common cause of vitamin B12 deficiency?

A

Pernicious anemia

24
Q

Autoimmune disorder involving destruction of parietal cells, which leads to intrinsic factor deficiency?

A

Pernicious anemia

25
Q

Besides pernicious anemia, what are some other causes of vitamin B12 deficiency?

A

Pancreatic insufficiency
Damage to terminal ileum
Dietary deficiency (RARE, except in vegans)

26
Q

What are the two most common causes of damage to the terminal ileum, which causes a vitamin B12 deficiency?

A 
Crohn disease
Diphyllobothrium latum (tapeworm)
27
Q

What are changes that occur to RBCs with vitamin B12 deficiency?

A

Macrocytic RBCs

28
Q

What changes occur to neutrophils with vitamin B12 deficiency?

A

Hypersegmented neutrophils

29
Q

Why is poor proprioception and vibratory sensation, along with spastic paresis seen with vitamin B12 deficiency?

A

Vitamin B12 is cofactor for the conversion of methylmalonic acid to succinyl CoA

With Vitamin B12 deficient→ there is an increased level of methylmalonic acid impairing the spinal cord myelinization

30
Q

With respect to serum Vitamin B12, serum homocysteine, and Methylmalonic acid, what are the laboratory results seen with a vitamin B12 deficiency?

A

Serum Vitamin B12→ decreased
Serum homocysteine→ Increased
Methylmalonic acid→ increased

31
Q

What laboratory finding allows differentiation between a folate deficiency and a Vitamin B12 deficiency?

A

Methylmalonic acid levels

Normal with folate deficiency

Elevated with vitamin B12 deficiency

2nd U2 Path (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions