Approach to Patients with Anemia Disease

Hematology

1. Approach to patients with anaemia

2. General principles Anaemia is a disorder of red blood cells Anaemia is a clinical sign of a disease not a diagnosis/disease Need to look for an underlying cause Its diagnosis is not that simple It is very common and important in the medical practice Most treatable causes of anemia can be diagnosed without marrow examination Always consider/rule out blood loss.

3. What is anaemia ? A decrease in the number of circulating red blood cell mass and there by O2 carrying capacity. It can also be defined as a reduction in haemoglobin concentration of blood with reference to healthy individuals of the same age group and sex . Most common hematological disorder by far Almost always a secondary disorder As such, critical for all practitioners to know how to evaluate / determine its cause / treat

4. Normal values can vary between labs, however the typical values for anaemia would be <13.0 g/dl in adult males and <11.5 in adult females. From the age of 2 years-puberty <11.0g/dl

5. Pathogenesis/pathophysiology Low haemoglobin decreases the oxygen carrying capacity of the blood. This is offset by the following mechanisms. 1. Redistribution of cardiac output: Blood flow from non-critical areas like the skin is diverted to critical organs like heart and brain. 2. Increased Oxygen Extraction: Anaemic patients have increased tissue oxygen extraction from the blood. This is not seen in organs like the heart and brain that already have high oxygen extraction.

6. 3..Changes in oxygen affinity of haemoglobin: Patients with chronic anaemia have increased of 2,3 diphosphoglycerate (2,3-DPG). 2,3-DPG shifts oxyhaemoglobin dissociation curve to the right and increases oxygen delivery. 4.Isovoluaemic haemodilution : Patients with anaemia have increased plasma volume. This allows maintaining a normal cardiac output.

7. Classification of anaemia Anaemia is usually classified using 2 types of classifications 1. Pathophysiology/ Aetiology classification 2. Morphological classification

8. Classification of anaemia A. Pathophysiology/ Aetiology Blood loss = Haemorrhagic Decreased production of erythroid cells (in the bone marrow)= Hypoproliferative anaemia Increased destruction of the erythroid cells (in peripheral circulation)= Haemolytic

9. Blood Loss Acute Traumatic Variety of sources Melena, hematemesis, menorrhagia Chronic Occult bleeding Colonic polyp/carcinoma

10. Decreased Production

11. Increased destruction Immune Mediated e.g. Auto-immune haemolytic anaemia (AIHA) Non-immune Mediated e.g. microangiopathic haemolytic anaemia (MAHA)

12. Classification of anaemia B. Morphology (based on FBP) Normochromic Normocytic (MCH & MCV are normal) Hypochromic Microcytic (MCH & MCV are low) Macrocytic (MCV is high)

13. CAUSES whwm 2014 15

14. How to approach a patient with anaemia ? A. Clinical History B. Physical examination C. Investigations including lab investigations and others

15. Clinical history Chief complaint and duration History of presenting illness Past medical history Family history Dietary history Drug history Social history Menstrual and obstetrical history in females System review

16. Chief complaint Main symptoms of anaemia are: Shortness of breath (SOB), particularly on exercise Weakness Lethargy Palpitation and Headache.

17. In older people Symptoms of heart failure (ankle edema, SOB..) Angina pectoris (chest pain) Intermittent claudication Confusion Visual disturbances due to retinal haemorrhage in severe anaemia of acute onset.

18. History of presenting illness Details about the main symptom; aggravated by, relieved by, accompanied with..

19. Family history Any similar problem in the family Draw a family tree if you are suspecting a hereditary condition

20. Dietary history Daily dietary intake in the main meals: breakfast, lunch, dinner

21. Drug history Ask about any drugs taken regularly eg NSAID as some drugs can cause bleeding from GIT

22. Menstrual and obstetrical history Age of menarche Ask about the menstrual cycle; regular, amount of bleeding, date of LMP History of pregnancies, any complications as Postpartum haemorrhage (PPH)

23. Physical examination General inspection Vital signs CVS Respiratory System Abdomen Lymph Nodes CNS Skin / mucosal pallor, Skin dryness, palmar creases Bald tongue, Glossitis Mouth ulcers, Rectal exam Jaundice, Purpura Lymph adenopathy Hepato -splenomegaly Breathlessness Tachycardia, CHF Bleeding, Occult Blood

24. Symptoms & Signs In some patients with severe anaemia there may be no or mild symptoms and signs while others with mild anaemia may be severely affected, this depends on Speed of onset: rapidly progressive anaemia more symptoms (no time for adaptation) Severity Age: elderly tolerate anaemia less well that the young

25. General Signs pallor of the mucous membranes Skin colour is not a reliable sign signs of hyperdynamic circulation ; tachycardia, a bounding pulse, cardiomegaly and a systolic flow murmur. Features of congestive heart failure specially in the elderly.

26. Specific signs These are associated with specific types of anaemia Koilonychia (spoon nails) with Iron deficiency anaemia (IDA) Jaundice with haemolytic anaemia Leg ulcers with sickle cell anaemia Bone deformities with thalassaemia

27. Laboratory investigations Full blood picture (FBP) this includes all the blood counts plus a blood smear to look at the morphology of cells Normocytic normochromic (MCV & MCH are normal) Microcytic hypochromic (MCV & MCH are low) Macrocytic (MCV is high)

28. Looking at the blood film Are all RBC of the same size ? Are all RBC of the same normal discoid shape ? How is the colour ( Hb content) saturation ? Are all the RBC of same colour / multi coloured ? Are there any RBC inclusions ? Are intra RBC there any hemo -parasites ? Are leucocytes normal in number and D.C ? Is platelet distribution adequate ?

29. Normocytic normochromic anaemia MCV 80-95 fL , MCH > 27 pg Chronic inflammatory diseases Malignancy Renal disease After acute blood loss Bone marrow failure (post-chemotherapy, infiltration by carcinoma..)

30. Hypochromic Microcytic anaemia MCV< 80 fL MCH< 27 pg Iron deficiency Thalassaemia Anaemia of chronic diseases (some cases) Sideroblastic anaemia (some cases) Lead poisoning

31. Hypochromic Microcytic anaemia Serum ferritin Transferrin saturation Serum Iron Total Iron Binding Capacity (TIBC) Soluble transferrin receptor Marrow iron store (invasive procedure) Retic hb Percentage of hypochromic cells

32. Hypochromic Microcytic anaemia Other investigations to look for the cause of anaemia as Hb analysis, stool examination for occult blood stool examination for ova and cysts Urine examination to check for haemoglobinuria or haematuria Radiological investigations eg : ultrasound endoscopy

33. IDA features Microcytic MCV < 80 fl , RBC < 6 µ RDW high Hypochromic MCH < 27 pg , MCHC < 30% Retic. count can be< 2 % Serum ferritin Very low < 30 (p mols /L) TIBC Increased > 400 (µg/ dL ) Serum Iron Very low < 30 (µg/ dL ) BM Fe Stain Absent Fe Response to Fe Rx Excellent

34. Macrocytic anaemia MCV> 95fL Megaloblastic anaemia ( vit B12 or folate def) Non- megaloblastic anaemia due to Alcohol, Hypothyroidism Liver disease, Myelodysplastic syndrome Aplastic anaemia , Acute haemolysis (due to reticulocytosis ) Drugs

35. Investigations of Macrocytic anaemia Reticulocyte count Serum vit B 12 , Serum folate and rbc folate Liver function test Thyroid function test Investigations for haemolysis (LDH, Coombs test..) Bone marrow exam if required

36. NH is a 50-year old male who has not had any primary care for the past few years. When he tried to donate blood last week, he was told that he was anaemic . He was referred to your clinic for evaluation. What would you do??