Intro to hematopoesis and bone marrow morph wk7w10 Flashcards Preview

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Flashcards in Intro to hematopoesis and bone marrow morph wk7w10 Deck (22):
1

Erythropoisis 

- regulated by erythropoietin, a hormone synthesized by the kidney

- nutrients required include iron, B-12, folate

- normal bone marrow function

2

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

3

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

 

 

4

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

 

5

Rouleaux formation

- increased paraproteins in the blood

- multiple myeloma

6

agglutination

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

7

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. 

8

Neutrophil development

myeloblast->promyelocyte->myelocyte->metamyelocyte->band->neutrophil

9

Neutrophils- primary defense against infections

Phagocytosis

Secretion of anti- microbial agents

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

10

Basophils

- 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

11

Eosinophils

- 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

12

Lymphocytes

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

13

Monocytes

Replenish the macrophage dendritic system

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

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

14

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

 

15

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

16

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

17

Platelets

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 

18

Platelet deveopment

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

19

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)

20

Thrombocythemia diseases

Primary- Myeloproliferative process- CML, PV, ET

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

21

Clinical findings of platelets

Petechae and purpura


History of easy or spontaneous bruising


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

22

Normal count but loss of platelet function

causes

Uremia- renal failure

Liver disease


Prosthetic valves


Aspirin or NSAIDs or other drugs (many!)


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