Intro to hematopoesis and bone marrow morph wk7w10 Flashcards Preview

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- regulated by erythropoietin, a hormone synthesized by the kidney

- nutrients required include iron, B-12, folate

- normal bone marrow function


RBC morphology and disease

1. microcytic

2. macrocytic

3. normocytic with abnormal shapes

1. iron deficiency, thalassemia

2. folate, B12 deficiency

3. hereditary spherocytosis, sickle cell disease


clincal presentation of iron deficiency

- fatigue, breathlessness

- pica- persistent compulsive desire to ingest certain food or non-edible items like ice, clay, plaster

- sore mouth, angular stomatitis, palor




Megaloblastic anemia

- B12 and folic acid deficiency

- bone marrow hypercellular with increased megablasts

- all hematopoetic lineages show nuclear to cytoplasmic dyssynchrony

- SMEAR= macrocytic anemia, hypersegmented neutrophils



Rouleaux formation

- increased paraproteins in the blood

- multiple myeloma



IgM mediated
Causes include viral infections like Influenza, Mycoplasma
Cold Agglutinin Disease


Neutrophils (PMNs)

Life span  is 5.4 days. Neutrophils play an important role as the first line of defense in bacterial infections

Primary granules- MPO, elastase, defensins, cathepsins

Secondary granules- lactoferrin

Tertiary granules- cathepsin, gelatinase

Granulocytes spend 9 days in the marrow, 3-6 hours in the blood and 1-4 days in the tissues. 


Neutrophil development



Neutrophils- primary defense against infections


Secretion of anti- microbial agents

Neutrophil extracellular trap (NET)- release fiber like material that forms a web around the organisms and kill them extracellularly



- affinity for basic dyes

Least common of the granulocytes representing 0.01- 0.3% of white cells

They have receptors that bind to IgE immunoglobulin that is involved in parasitic infections and allergies.

Contains granules with histamine, heparin, elastase, proteoglycans that are released during inflammatory response to parastiic infections and allergens such as pollen, helminths

Basophilia – increased basophils can be seen in chronic myeloid leukemia



- affinity for acidic dyes

- Constitute 1-6% of the total white cells. Life span of 8-12 hours in circulation

- Involved in allergies and infections (parasitic)

- Secrete numerous leukotriens cytokines and mediators of allergic response, asthma pathogenesis



Mononuclear cells-
T-cell – thymus derived cells ,cellular immunity,T-helper cells- CD4

T-suppressor cells- CD8
B-cells- bone marrow derived, humoral immunity ( secrete antibody)

NK- cells- Natural killer cells

Lymphopenia- HIV , reduced CD4 counts
Lymphocytosis- Leukemia/ lymphomas



Replenish the macrophage dendritic system

- Phagocytosis
- Antigen presentation activating the complement pathway
- Cytokine production

Mononuclear cells with a kidney shaped nucleus and pale blue  cytoplasm with vacuoles


Reasons for leukocytosis

1. neutrophila

2. eosinophila

3. basophilia

4. lymphocytosis

1. neutrophila: bacterial infections, heat stroke, stress neutrophilia, drugs, steroids, hereditary neutrophilia

2. eosinophila: parasitic infections, allergies, lymphoma, cancers

3. basophilia: CML

4. Lymphocytosis: TB, viral infections, pertussis, infectious mononucleosis

5. Monocytosis: chronic infections, lupus, ulcerative colitis, malaria



Plasma Cells

Originate in the bone marrow and are terminally differentiated B-lymphocytes

Plasma cells secrete abundant immunoglobulins and play an important role in humoral immunity

Usually not circulate in the peripheral blood


Multiple Myeloma

Multiple Myeloma – Neoplasm arising from malignant plasma cells. It affects the bone marrow and the normal hematopoetic elements are replaced by malignant plasma cells.

The neoplastic plasma cells secrete paraproteins which causes kidney problems and interferes with the normal antibody secretion by plasma cells.

Hence patients are prone to cytopenias due to bone marrow involvement, renal failure and accumulation of paraproteins in abnormal sites leading to functional defect.

Clinical features of MM is CRAB: calcemia, renal failure, anemia , bone lesions



Platelets are cytoplasmic blebs arising from the megakaryocyte.

The normal life span of platelets is 7-10 days.

Normal platelet count 150-350,000.

The hormone responsible for platelet production is thrombopoetin produced by the liver and kidney 


Platelet deveopment

hematopoietic stem cell->promegakaryocyte->megakaryocyte->platelets released


Thrombocytopenia diseases

DIC- disseminated intravascular coagulation

TTP- thrombotic thrombocytopenic purpura
ITP- immune thrombocytopenia

Medications- heparin, antibiotics, H2 blockers

Bonemarrow Aplastic Anemia, Leukemia, MDS(myelodysplastic syndrome)


Thrombocythemia diseases

Primary- Myeloproliferative process- CML, PV, ET

Secondary-  acute phase reactant, iron deficiency, acute blood loss, post splenectomy, steroids, epinephrine, chronic infections


Clinical findings of platelets

Petechae and purpura

History of easy or spontaneous bruising

Mild to moderate mucosal membrane bleeding
- Gingival bleeding, menorrhagia, epistaxis


Normal count but loss of platelet function


Uremia- renal failure

Liver disease

Prosthetic valves

Aspirin or NSAIDs or other drugs (many!)

Congenital  (intrinsic platelet defects)- Bernard Soullier syndrome, Glanzmann’s thrombasthenia