Lecture 1 - Intro To anaemia

Question 1

How do RBC make energy : glycolysis

Answer 1

• glycolysis is the first step in the breakdown of glucose to extract energy
• does not use oxygen, and can take place under anaerobic conditions

Question 2

Glycolysis two phases

Answer 2

1) Traps glucose molecule and uses energy to modify it: six carbon molecule splits into 2 times 3 carbon molecules
2) extracts energy from the molecules and stores it in the form of ATP and NADH using the pyruvate kinase enzyme

Question 3

Survival of RBC: dealing with reactive oxygen species

Answer 3

• ROS convert ferrous of haemoglobin to Ferric of methaemoglobin - doesnt transfer O2
• damages the lipid membrane - short life span
• glutathione scavenges ROS
• oxidized form of gluthatione is regenerated by glutathione reductase
• Hexose monophosphate shunt generates the necessary NADPH and uses G6PD

Question 4

Erythropoietin

Answer 4

• hormone which controls red cell production: works on red cell precursors in the bone marrow and promotes differentiation
• produced in kidney under hypoxic stress in adult
• produced in liver in the foetal and perinatal period

Question 5

Definition of Anaemia

Answer 5

• reduction in red cell number and haemoglobin concentration of blood
• hemoglobin is the oxygen carrying pigmented proteins in red cells
• results in a reduction in the oxygen carrying capacity of the blood

Question 6

Symptoms of anemia depend on:

Answer 6

• rapidity of onset
• general health
• severity of anemia

Question 7

Symptoms of anemia

Answer 7

• tiredness, headaches
• dizziness
• SOB
• palpitations
• chest pain

Question 8

Pallor

Answer 8

• conjunctivae

- palmar crease

Question 9

Cardiac decompression

Answer 9

• tachycardia
• postural hypotension
• congestive cardiac failure

Question 10

Signs of ane,ia

Answer 10

• angular stomatitis, glossitis, koilonychia
• jaundice
• underlying systematic illness

Question 11

Useful laboratory indices in anemia

Answer 11

• hemoglobin
• MCV
• blood film
• Reticulocyte count

Question 12

Automated counters

Answer 12

• haemoglobin measured by spectrophotometry at 540nm
• RBC count measured by particle counter
• MCV directly measured electronically
• MCHC calculated from haemoglobin and haematocrit
• heamatocrit calculated from red cell number and MCV
• white cells and platelets: measured optically via electrical impedence, light scatter, fluorescence and laser

Question 13

Haemoglobin normal range

Answer 13

• male: 130-170
• female: 120-150
• higher in newborn
• pregnancy: 10-20 lower due to disproportionate rise in plasma and red cell volumes

Question 14

• Mean corspuscular volume reference range

Answer 14

• 80-100 fl

Question 15

Principles of romanowsky stain on blood film

Answer 15

• basic cellular elements react with acidic dye (eosin) and stain red-orange. Eg: hemoglobin
• acidic cellular elements react wit basic dye (methylene) and stain blue (eg: DNA)

Question 16

Red cell development

Answer 16

• bone marrow proliferation and maturation is 3-5 days
• reticulocytes - bone marrow to blood: 3-4 days
• circulating mature red cell for 120 days
• vitamin B12 and folate are required for DNA synthesis and nuclear maturation

Question 17

Reticulocyte

Answer 17

• young and immature red cells
• have residual RNA
• therefore have a blue blush
• on a blood film is called polychromasia

Question 18

Reticulocyte count

Answer 18

• identified by staining residual RNA
• automated: residual RNA stained with flyuorescent dyes and enumerated by flow cytometry
• reference range: 50-100x10^9 g/L

Question 19

Possible causes of anemia

Answer 19

• decreased production: deficiencies or systemic illness
• increased loss: bleeding
• shortened life span or increased destruction: haemolytic anemias, either inherited or acquired

Question 20

When is anaemia due to primary bone marrow pathology

Answer 20

• when more than one cell line is abnormal: increased or decreased white cells and platelets

Question 21

If MCV

Answer 21

• iron deficiency due to chronic blood loss

- inherited Hb abnormality: thalassaemias

Question 22

If MCV normal

Answer 22

• acute blood loss
• systemic illness
• primary BM pathology

Question 23

If MCV > 100 fl

Answer 23

• B12 and folate deficiency
• haemolysis
• liver disease

Question 24

Hypochromic microcytic cells with anisopoikilocytosis

Answer 24

Iron deficiency anaemia

Question 25

Target cells

Answer 25

• in liver disease

Question 26

Macrocytes

Answer 26

• in B12 or folate deficiency

Question 27

Spherocytes

Answer 27

• in haemolysis

Question 28

Sickle cell

Answer 28

• sicle cell anaemia: an inherited abnormal Hemoglobin

Question 29

Rouleaux

Answer 29

• in myeloma

Question 30

• primitive white cells called blasts

Answer 30

• in acute leukaemia: a bone marrow disease

Question 31

Increased reticulocytes means

Answer 31

• increased BM production
• acute hemorrhage
• reduced red cell life span: haemolysis
• response to replenished iron, B12 and folate

Question 32

Normal or reduced reticulocytes means reduced BM production

Answer 32

• not enough iron, B12 or folate
• systemic illness
• bone marrow pathology

Question 33

Further laboratory tests

Answer 33

• iron studies: transferrin saturation and ferritin
• B12 and folate levels
• heamollytic screen: bilirubin, LDH, haptoglobin, DCT
• tests of inherited causes of haemolysis

Question 34

Systemic illness tests

Answer 34

• infection
• autoimmune disease: serology
• renal impairment: creatinine
• hepatic dysfunction: LFT

Question 35

bone marrow biopsy

• aspirate vs trephine

Answer 35

• performed to confirm or exclude a suspected diagnosis
• site: posterior iliac crest or sternum, tibia in neonates
• aspirate: to assess cell number, maturation and morphology
• trephine: to assess cellularity, architecture and abnormal cellular infiltrate

Question 36

Treatment of anemia

Answer 36

• transfusion in circulatory compromise
• replace missing iron, B12 or folate
• rectify shortened life span in case of haemolysis
• treat underlying condition