Presentation is loading. Please wait.

Presentation is loading. Please wait.

Clinical pathology department SCU

Similar presentations

Presentation on theme: "Clinical pathology department SCU"— Presentation transcript:

1 Clinical pathology department SCU
Macrocytic Anemia Clinical pathology department SCU

2 Normal blood cells

3 Complete Blood Count (CBC)
Normal red blood cells

4 Definition An (without) -emia (blood): a reduction below normal in hemoglobin or red blood cell number

5 Symptoms and signs of Anemia
None if mild Fatigue Breathlessness Dizzines Pale Skin & mucous membranes Jaundice ( if hemolytic) Tachycardia

6 Differential Diagnosis Using MCV
Macrocytic anemias (MCV = 150 fl): > normal cells Normocytic (MCV = fl): cells are normal in volume Microcytic anemias (MCV = 50 fl): cells are < normal

7 Macrocytic anemia Defined as MCV > 100 femtoliters
Identified by peripheral blood smear or automated RBC indices Smear is more sensitive in detecting early macrocytic changes and small numbers of macrocytes Cell morphology can aid in determining etiology of macrocytosis

8 Common Causes of Macrocytosis
% of cases Alcohol abuse 36% B12 or Folate deficiency 21% Chemotherapy or drugs 11% Hemolysis or bleeding 7% Liver disease 6% Primary bone marrow disorders 5% Hypothyroidism Others 12%

9 Megaloblastic Anemia Defective DNA synthesis leads to nuclear/cytoplasmic asynchrony B12/folate deficiency Macrocytic anemia with hypersegmented neutrophils

10 BIG cells! Megaloblastic Anemia retarded DNA synthesis
unimpaired RNA synthesis BIG cells! immature nucleus mature cytoplasm

11 How is B12 involved? B12 (and folate) are required for DNA synthesis.
Slowed DNA synthesis means big, immature nucleus Cytoplasm (with RNA in it) matures just fine B12 is also required for conversion of homocysteine to methionine ↑ homocysteine = atherosclerosis! ↓ methionine = subacute combined degeneration

12 Megaloblastic anemia

13 Megaloblastic anemia

14 Reticulocyte Count (In the Diagnosis of Anemia)
Useful in determining response and potential of bone marrow. Reticulocytes are non-nucleated RBCs that still contain RNA. Visualized by staining with supravital dyes, including new methylene blue or brilliant cresyl blue; RNA is precipitated as dye-protein complex. Normal range is % of all erythrocytes. If bone marrow responding to anemia, should see increases in retic count. Newborns have higher retic count than adults until second or third week of life.

15 Retics Slide


17 Thank You

Download ppt "Clinical pathology department SCU"

Similar presentations

Ads by Google