Erythropoiesis

Question 1

Erythropoiesis in infant/childhood vs adulthood

Answer 1

Infants/kids:
Entire skeleton
Sternum
Pelvis
Ribs
Cranial bones
Vertebrae
Long bones of leg

Adulthood:
Axial skeleton
Vertebrae
Sternum
Ribs
Pelvis

Question 2

Adult hemoglobin

Answer 2

HbA

Alpha 2 (Chr 10)
Beta 2 (Chr 11)

Question 3

Fetal hemoglobin

Answer 3

HbF
Alpha 2
Gamma 2

Gamma has lower affinity for 2,3 DPG, higher affinity to O2 than beta in adult
-allows transfer of O2 to fetus

Question 4

Relative polycythemia

Answer 4

Low plasma volume

Normal number of RBC

Question 5

Absolute polycythemia

Answer 5

Normal plasma volume

Elevated number RBCs

Question 6

HbA

Answer 6

97% of normal hemoglobin

a2b2

Question 7

HbA2

Answer 7

2% normal hemoglobin

a2d2 (delta)

Question 8

HbA1c

Answer 8

Poorly controlled diabetes

A2b2-glucose

Question 9

HbF

Answer 9

Fetal hemoglobin

a2 gamma2

Question 10

Hb Gower

Answer 10

Embryonic hemoglobin

2 zeta, 2 epsilon

Question 11

HbS

Answer 11

Sickle cell hemoglobin

A2Bs2
Glu->val in beta chain

Question 12

HbC

Answer 12

Hemoglobin C disease
A2Bc2

Glu -> lys in beta chain

Question 13

Hb Bart’s

Answer 13

Severe alpha thalassemia

Gamma4 – no alpha chains

Question 14

HbH

Answer 14

Severe alpha thalassemia

Beta 4 – no alpha chains

Question 15

Polycythemia vera

Answer 15

Monoclonal proliferation of RBCs

Benign neoplasm

Question 16

Polycythemia/Erythrocytosis

Answer 16

Chronic hypoxia

• pulmonary dz
• OSA
• cyanotic heart dz
• high altitudes

inappropriate elevation of EPO
-EPO producing tumor

60% Downs at birth

Question 17

EPO producing tumors

Answer 17

“Potentially Really High Hematocrit”

Pheochormocytoma
Renal cell carcinoma
Hepatocellular carcinoma
Hemangioblastoma

Question 18

Draw out heme synthesis

Answer 18

Page 682

Question 19

Acute intermittent porphyria

Answer 19

Deficient uroporphyrinogen-1-synthase
(porphobilinogen deaminase)

Abd pain – neuropathic
Port wine urine
Polyneuropathy
Psych disturbances

Triggered by drugs:
Barbiturates
Seizure durgs
Rifampin
Metoclopramide

Tx: glucose and heme to inhibit delta-ALA synthase (reduce heme synthesis)q

Question 20

Porphyria cutanea tarda

Answer 20

MC

Deficient in uroporphyrinogen decarboxylase

Blistering of skin, photosensitivity –esp hands

Tea colored urine
Hypertrichosis
Facial hyperpigmentation
Assoc w/ Hep C and alcoholism

Question 21

Lead poisoning

Answer 21

Microcytic anemia
Basophilic stippling
Neurologic manifestations

Block delta-ALA dehydratase and Ferrochelatase in heme synthesis pathway

Global encephalopathy: memory loss, delirium, mental deterioration
Foot/wrist drop

Lead lines – gingival – burton’s lines
-metaphyses

colicky abd pain

-> renal failure in adults

Adults: HA, memory loss, demyelinization

Tx:
EDTA, succimer
Severe in kids (elevated LFTs): dimercaprol + succimer