Hematology Flashcards
Definition of Anemia
decrease in the number of circulating RBC mass/ Oxygen carrying capacity.
*almost always a secondary disorder
cut off points for RBC, Hb & Hct in Male and Female
RBC:
male < 4.4 T/L
female < 3.8 T/L
Hb:
male < 140 g/L
female < 120g/L
Hct
male < 42%
female < 37%
Symptoms of Anemia depend on?
Severity of the Anemia
Rapidity of onset
Patient’s age and cardiovascular status
examples of symptoms of Anemia
Cardiovascular and Respiratory
- tachycardia, palpitation, dyspnoe, angina
Neurologic
- headache, dizziness, fatigue
Skin
- pallor of skin, mucous membrane, nail beds
Gastrointestinal
- anorexia, nausea, diarrhoea, constipation
Genitourinary
- menstrual irregularity, amenorrhoea, loss of libido/potency
Classification of anemias based on MCV (mean corpuscular volume)
microcytic, Normocytic, Macrocytic
classification of anemias based on MCHC/MCH (mean corpuscular haemoglobin / mean corpuscular haemoglobin concentration)
hypochromic, normochromic, Hyperchromic
Decreased RBC production could be due to?
- defects in myeloid stem cells
- defects in erythropoietin
- defects in RBC maturation (e.g altered Hb synthesis or altered DNA synthesis)
Increased Loss / excess destruction could be due to?
Haemorrhage
Hemolysis
Factors that control erythropoiesis
IL-3
IL-9
GSF (granulocyte stimulating factor) GM-CSF
EPO (erythropoietin)
Where is EPO produced and what stimulates it’s secretion?
Kidney (90%) Liver (10%)
in response to cellular HYPOXIA
but there is a constant low level (10mU/mL) released for RBC turnover
Aplastic anemia definition
characterised by an Acellular or Hypocellular bone marrow which causes Pancytopenia (RBC, WBC, platelets)
Pathogenesis of Aplastic anemia
- qualitative or quantitative abnormalities of the pluripotent stem cells
- abnormal humoral or cellular control of hematopoiesis (GM-CSF, IL-3)
- abnormal or “hostile” hematopoietic microenvironment (e.g damaged stromal cells)
- immunologic suppression of hematopoiesis (e.g humoral/antibody mediated, cell mediated/T-cell abnormalities, lymphokine mediated)
Pathogenesis of anemia in Chronic renal failure
Renal excretory failure =
- Lower Hematocrit caused by Hydremia (excessive fluid volume)
- Reduced RBC survival (metabolic or mechanical)
- Direct marrow suppression (uremic toxins)
- Deficiencies of certain nutrients ( iron, folate chronic dialysis)
- impaired platelet function (bleeding tendencies)
- decreased EPO production!
pathogenesis of anemia in Cirrhosis
- alteration in the lipid composition of RBC membranes
- increased plasma volume associated with cirrhosis
- enlarged Spleen - portal hypertension
- Acanthocytes*
what is MCV and it’s normal range?
The average volume of a RBC in a specimen
= 80-99 fL
** Hct / RBC No. = Volume **
what is MCH and it’s normal range?
The average content of Hb per RBC
= 27-34 pg
** Hb / RBC No. = MCH **
what is MCHC and it’s normal range?
The average content of Hb per unit volume of RBC (concentration)
= 315-360 g/L
** Hb / Hct = MCHC ** OR ** MCH / MCV **
List Anemia of endocrine diseases with a brief description
Hypopituitarism - normochromic, normocytic
- androgens & groth hormone
(TSH & GH)
Hypothyroidism - micro- , macro- & normo-cytic
Thyroid hormones stimulate the proliferation of erythrocyte precursors both directly and via EPO production enhancement.
= adaptation of decreased BMR (less O2 needed), Hypoplastic anemia, menorrhagia/malabsorption of iron, Pernicious anemia
Hyperparathyroidism - normocytic, normochromic
= PTH down regulates EPO receptors on progenitor cells in the bone marrow
List Anemias involving altered haemoglobin synthesis
- microcytic, Hypochromic *
- Iron deficiency
- Anemia of chronic disease (some)
- Thalassemias
- Hemoglobinopathy
- Sideroblastic anemias (lead toxicity)
What is the major difference with Iron stores in the body during Iron Deficiency Anemia?
The Stored Iron = 0mg
instead of 1000mg
The absorption is changed to 2-10 mg/day
instead of the normal 1mg/day
What results do you expect to see in the blood test and blood smear for Iron deficiency anemia?
- Decreased FERRITIN
- Decreased serum Fe
- Decreased Sat%
- Decreased Hgb, Hct & RBC
- Decreased MCV, MCH, MCHC
- Increased Transferrin/TIBC
- Increased sTfR
- Increased RDW
- Increased Platelet count
blood smear
= Microcytes + Anisopoikilocytosis + Target Cells!
list some possible causes that would be underlying the Iron Deficiency Anemia
- ) Chronic bleeding e.g GI bleeding, uterine bleeding
- ) von Willebrand disease
- ) Myoma
- ) Growth / Pregnancy
- ) Strong menstruation
- ) Malabsorption (Celiac Disease)
- ) low intake / gastrectomy
- ) Parasite infection (worms)
List some symptoms specific to Iron Deficiency Anemia
Oral Lesions - angular cheilosis, Glossitis, Stomatitis
Dysphagia
Nail Lesions - flattening, brittle, spoon shaped (koilonychia)
Pica - compulsive ingestion of nonnutritive substances e.g clay, dirt, paint, Ice, laundry starch
