Brainscape's Knowledge GenomeTM

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


See full index

Hematology > Megaloblastic Anemia > Flashcards

Megaloblastic Anemia Flashcards

1
Q

Macrocytic anemia definition

A

anemia with macrocytes present (> 100 fL MCV)

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

megaloblastic anemia is one type of _ anemia

A

macrocytic

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

megaloblast

A

large and abnormal precursor cell in the bone marrow exhibiting asynchrony

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

Asynchrony in macrocytic anemia

A

results from defective nucleus maturation

Due to impaired DNA synthesis

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

Thymidine triphophate (TPP) synthesis is inhibted causing

A
  • nuclear fragment
  • cell destruction
  • impaired cell division
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

in macrocytic anemia, RNA is not affected

A

The cytoplasm matures normally

Normal MCHC

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

Ineffective erythropoiesis

A
  • Increased RBC precursors in BM
  • RBC precursor cells are fragile
  • RBC precursor cells die prematurely in BM
  • Decreased RBC release into PB
  • Decreased RBC in PB stimulates EPO production
  • EPO stimulates RBC maturation and production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

ineffective granulopoiesis

A
  • increase WBC precursors in BM
  • giant metamyelocytes die in BM
  • Decrease in mature WBC released to PB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

ineffective thrombopoiesis

A
  • Increased megakaryocytes in BM that are abnormal
  • impaired thrombopoiesis
  • decrease in platelets in peripheral blood = thrombocytopenia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Causes of Impaired DNA syntehsis (TTP synthesis inhibition)

A

Vitamin B12 Deficiency
- aka “Pernicious Anemia” when due to lack of intrinsic factor

Folic Acid deficiency

Drugs that impair availability of either ^

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

Vitamin B 12 - Cobalamin

A
  • Produced by microorganisms and fungi
  • present in foods of animal origin
  • (can be aproblem for strict vegans, since plants do not contribute B12 to diet).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

USA daily diet of Vitamin B12

A

5-30 um

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

recomended dietary intake of B12

A

2 ug/day

increased in pregnancy/breastfeeding, infancy, edlerly

Requirement is low, and storage rate is high. It can take several years for vitamin B12 deficiency to develop

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

How do we get vitamin B12?

A

Vitamin B12 in diet binds to Intrinsic factor (IF)

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

IF

A

glycoprotein secreted by parietal cells (stomach)

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

Complexed B12+IF travels to ielum, where B12 is absorbed

A

B12 enter PB in portal vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In portal vein, B12 attaches to Transcobalamin II (or similar carrier proteins)

A

Transcobalamin II (TC II) - main transport protein of cobalamin to tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

TC II takes B12 to the bone marrow, liver or other tissues

A

stored for 2-7years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Transcobolamin II

A

main transport protein of covalamin to the tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Diet - B12 defiency

A

strict vegans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Impaired absorption - B12 Deficiency

A

Lack of intrinsic factor –> Pernicious anemia
Ileum resection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Pernicious anemia

A

lack of intrinsic factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Microorganism competition - Vitamin B 12 deficiency

A

Diphyllobothrium latum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Drug - Vitamin B 12 deficiency

A

Colchine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Zollinger - Ellison syndrome . B12 defiency

A

Hypersecretion of HCl

26
Q

Increased requirement - B12 deficiency

A

pregnancy, infancy, elderly

27
Q

Folic acid - Synthetic
Folate - Natural

A

Water soluble vitamin (B9)

  • high concentration in green leafy vegetables, fruits, dairy, animal products
  • synthesizes by microorganisms in our intestines, but not absorble
28
Q

B9
Heat liable?
USA Daily diet
Recomended

A

Destroyed by over cooking

USA Daily diet - 400-600 ug

Recomended (50-100 ug)
- increased in pregnancy, infancy, lactation

Primarily stored in the liver (80%)

29
Q

Folic acid (folate) deficiency causes

A
  1. diet/ inadequate intake
  2. increased requirement
    - pregnancy, infancy, brest feeding
  3. Impaired absorption
    - tropical sprue infection
    - celiac disease
  4. Drug induction
    - methotrexate
30
Q

B12 and Folate (B9) deficiency: Clinical manifestations

A
  • Pallor, weakness, lightheadedness
  • Shortness of breath
  • Glossitis
  • Graual onset
31
Q

glossitis

A

smooth sore tongue

32
Q

Only B12 Deficiency

A

Peripheral nerves

Neurological manifestations 4 P’s
1. Peripheral neuropathy
2. Pyramidal Tract signs
3. Posterior Spinal Column Degeneration
4. Psychosis (megaloblastic madness)

Paresthesia

Fever of unknown origin (FUO)

33
Q

Paresthesia (B12 deficiency)

A

tingling / prickling feeling

34
Q

Anemia: Macrocytic, normochromic Anemia

A
  • Low hemoglobin
  • high MCV: 100-160 fL
  • Normal MCHC
35
Q

Pancytopenia

A
  • Low RBC count
  • Low WBC count
  • Low/Borderline PLT count
36
Q

Anisocytosis
(megaloblastic)

A

oval macrocytes

37
Q

inclusions
(megaloblastic)

A

howell jolly bodies
cabot rings (rare)

38
Q

Poikilocytosis

Megaloblastic

A

teardrop cells

39
Q

reticulocytopenia

A

for the level of compensation expected

40
Q

Peripheral smear WBC in megaloblastic anemia

A
  • Hypersegmented neutrophils
  • Necrobiotic neutrophils
41
Q

Bone marrow in Megaloblastic anemia

A

Decreased myeloid : Erythroid ratio

1:3 - 1:1

Erythroid hyperplasia

42
Q

ineffective erythropoiesis

A

megaloblasts

43
Q

Serum B12 Test

A

Decrease in B12 deficiency

44
Q

Serum folate

A

Decrease in Folate deficiency

45
Q

Reticulocyte production index Test

A

Decrease, due to ineffective erythropoiesis

46
Q

Serum bilirubin test

A

Increased indifrect bilirubin

47
Q

Lactate dehydrogenase (LDH)

A

Increase, due to destruction of megaloblasts

48
Q

Urinary urobilinogen test

A

increase, due to RBC destruction

49
Q

Vitamin B12 deficiency

Treatment

A

lifelong vitamin therapy
- oral dose
- intramuscular or subcutaneous dose

Therapy is monitored by reticulocyte counts

Transfusion only in severe cases

50
Q

Folic acid deficiency

A

Oral dose for couple of weeks

Prophylaxis recomended for pregnancy and dialysis patients

51
Q

aplastic anemia

A

hypoproliferative, disorder wirh cellular depletion and reduced production of all blood cells, aka pancytopenia
- cytopenia
- pancytopenia

52
Q

cytopenia

A

abnormalities or deficiencies in specific blood cell elements

53
Q

pancytopenia

A

depression of each of the normal bone marrow elements

54
Q

aplastic anemia - possible mechanisms

A
  • Antibody directed to stem cell antigen
  • T lymphocytes suppress stem cell proliferation
55
Q

Aplastic anemia

A
  • > 95% is aquired
  • <5% is congenital
56
Q

Acquired Aplastic Anemia

A

**- Idiopathic = 40-70% **

  • Secondary = 30-60%
57
Q

Idiopathic/Primary anemia
(Acquired Aplastic Anemia)

MAJORITY OF CASES

A
  • 40 - 70 % of cases
  • no clear cut cause
  • not a result of another condition
58
Q

Secondary

Acquired Aplastic Anemia

A
  • 30-60%
  • External, chemical, physical or infectious agent initates mechanism
59
Q

chemical agents - secondary acquired aplastic anemia

A

benzene
arsenic
many more

60
Q

drugs - secondary acquired aplastic anemia

A
  • Chloramphenicol
  • phenylbutazone
61
Q

infections - secondary acquired aplastic anemia

A

Hepatitits
Epstein Barr Virus
Cytomegalovirus

62
Q

miscellaneous secondary acquired aplastic anemia

A

Pregnancy
Malnutritoin
Immunologic dysfunction

Hematology (36 decks)

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