RBC DISORDERS-2

Question 1

The attached image compares a marrow aspirate from a normal individual with the BM aspirate from an individual with the condition described below:

Vegetarian

Pallor, lemon yellow tinged skin

beefy red tongue

PS: hypersegmented neutrophils

What are the 3 key BM findings in this condition?

Deborah Dalmeida MD

Answer 1

1. Nuclear cytoplasmic dysynchrony - cytoplasmic differentiation, as assessed by increasing hemoglobin production, is normal, nuclear maturation is retarded
2. markedly hypercellular
3. giant metamyelocytes and band forms

Deborah Dalmeida MD

Question 2

1. 2 features of anemia of chronic renal failure on a peripheral smear
2. Why do they develop anemia?

Deborah Dalmeida MD

Answer 2

1. normocytic anemia,presence of burr cells
2. diminished synthesis of EPO

Deborah Dalmeida MD

Question 3

peripheral pancytopenia (decreased RBCs, WBCs, platelets)

reticulocyte index <2

marrow hypoplasia

No splenomegaly

Deborah Dalmeida MD

Answer 3

Aplastic anemia

Deborah Dalmeida MD

Question 4

What features on a peripheral smear are characteristic of myelophthisic anemia?

Deborah Dalmeida MD

Answer 4

abnormal release of nucleated erythroid precursors and immature granulocytic forms ka leukoerythroblastic reaction

teardrop cells

Deborah Dalmeida MD

Question 5

two important biochemical reactions requiring Vitamin B12

Deborah Dalmeida MD

Answer 5

1. conversion of methylmalonyl-coenzyme A (CoA) to succinyl-CoA
2. conversion of homocysteine to methionine.

Deborah Dalmeida MD

Question 6

autoimmune disorder characterized by the destruction of gastric parietal cells

1. What are the 2 types of antobodies produced?
2. How does this disorder lead to megaloblastic anemia?

Deborah Dalmeida MD

Answer 6

1. Antibodies against parietal cells and antibodies against intrinsic factor
2. Parietal cells are the source of IF. Without intrinsic factor, food cobalamin cannot be absorbed in the distal ileum

Deborah Dalmeida MD

Question 7

Time duration before a reticulocyte repsonse is observed in acute blood loss?

Deborah Dalmeida MD

Answer 7

5-7 days

Deborah Dalmeida MD

Question 8

Differentiate folic acid versus Vit B 12 deificiency

Deborah Dalmeida MD

Answer 8

decreased folate levels in the serum or red cells.

serum homocysteine levels are increased, but methylmalonate concentrations are normal

neurologic changes do not occur.

Deborah Dalmeida MD

Question 9

List 4 causes for Vitamin B12 deficiency apart from decreased intake.

Deborah Dalmeida MD

Answer 9

a. gastrectomy
b. ileal resection/disease
c. fish tapeworm infestation
d. bacterial overgrowth in blind loops and bowel diverticula

Deborah Dalmeida MD

Question 10

How does methotrexate cause folic acid deficiency?

Deborah Dalmeida MD

Answer 10

Inhibits dihydrofolate reductase

Deborah Dalmeida MD

Question 11

most common cause for folic acid deficiency

Deborah Dalmeida MD

Answer 11

alcoholism

Deborah Dalmeida MD

Question 12

Lab findings in Vit B12 deficiency apart from PS and BM

Deborah Dalmeida MD

Answer 12

low serum vitamin B12 <200pg/ml

elevated serum levels of homocysteine

Elevated methyl malonic acid

MCV >110 fL

Deborah Dalmeida MD

Question 13

Why do you get a slight increase in the level of nonconjugated bilirubin in the serum and a marked increase in serum lactate dehydrogenase (LDH) in megaloblastic anemia?

Deborah Dalmeida MD

Answer 13

increased rate of apoptosis of erythroid precursor cells due to derangement in DNA synthesis

Deborah Dalmeida MD

Question 14

Stomach morphology in pernicious anemia

Deborah Dalmeida MD

Answer 14

Fundic gland atrophy

Intestinal metaplasia

Deborah Dalmeida MD

Question 15

features of megaloblastic anemia on peripheral smear

Deborah Dalmeida MD

Answer 15

macro-ovalocytes

Anisocytosis

Poikilocytosis

Neutrophils are larger than normal and show nuclear hypersegmentation, having five or more nuclear lobules instead of the normal three to four

reticulocyte count is low

Deborah Dalmeida MD

Question 16

1. In whom does Parvovirus B19 infection trigger an aplastic crisis?
2. How does it trigger an aplastic crisis?

Deborah Dalmeida MD

Answer 16

1. In persons with moderate to severe hemolytic anemias, even a brief cessation of erythropoiesis results in rapid worsening of the anemia, producing an aplastic crisis.
2. attaches to P antigen on the RBC membrane and destroys red cell progenitors

Deborah Dalmeida MD

Question 17

Name the type of anemia described below:

space-occupying lesions replace normal marrow elements

Deborah Dalmeida MD

Answer 17

Myelophthisic anemia

Deborah Dalmeida MD

Question 18

2 possible causes for myelophthisic anemia

Deborah Dalmeida MD

Answer 18

1. metastatic cancer- breast, lung, and prostate
2. granulomatous disease

Deborah Dalmeida MD

Question 19

1. 3 Signs of Subacute combined degeneration of the Spinal Cord
2. What is the reason for demyelination?

Deborah Dalmeida MD

Answer 19

1. posterior column (PC) - loss of vibratory sensation and proprioception (joint sense).

lateral corticospinal tract (LCST) - spasticity.

dorsal spinocerebellar tract (DSCT) - ataxia.

2. lack of methyl-B12 for conversion of homocysteine to methionine. ↓SAM → ↓methyl group for Phosphatidylethanolamine conversion to Phosphatidylcholine for incorporation into myelin

Deborah Dalmeida MD

Question 20

List 3 causes for pure red cell aplasia

Deborah Dalmeida MD

Answer 20

Parvovirus B19 infection

Diamond-Blackfan syndrome

Thymomas

Deborah Dalmeida MD

Question 21

Identify this condition

a. normocytic normochromic anemia with reticulocytopenia
b. presents during the first 6 months of life
c. Short stature

Craniofacial – snub nose, wide spaced eyes

Thumb abnormalities – triphalangeal etc

Deborah Dalmeida MD

Answer 21

Diamond Blackfan Syndrome

Deborah Dalmeida MD

Question 22

Which enzyme levels are elevated in Diamond Blackfan Syndrome?

Deborah Dalmeida MD

Answer 22

erythrocyte Adenosine deaminase

Deborah Dalmeida MD