intro to heme

Question 1

Fetal versus adult hematopoeisis

Answer 1

Fetal: cells develop at 4-5 weeks gestation and migrate to liver, bone marrow, thymus, and spleen to undergo hematopoiesis
Adult: primary hematopoietic organ is bone marrow. even though there is a decrease in the amount of active bone marrow as we age, our body still makes the same amount of product

Question 2

Normal hematopoiesis flow

Answer 2

Stem cell > Myeloid stem cell > Erythroblast (RBCs), Megakaryoblast (Platelets), Myeloblast (PMNs, eosinophils, and basophils), or Monoblast (monocytes)OR Stem cell > Lymphoid stem cell > Pre B lymphocyte (Plasma cell) or Pre T lymphocyte (Mature T cell)

Question 3

Causes of bone marrow failure (general categories)

Answer 3

Nutritional deficiency
Marrow toxinsInfections
Marrow replacement
Autoimmune disease
Primary bone marrow diseases

Question 4

Requirements for hematopoiesis

Answer 4

Healthy bone marrow
Hormones/Cytokines-EPO from kidney, TPO from liver, and growth factors
Nutritional factors-iron, folate, vit B12

Question 5

What does the reticulocyte asses for

Answer 5

Reticulocytes are immature RBCs, newly released from marrow, contain RNA that can be stained; if there is a high amount check bone marrow