Evaluation of anaemia

MD student, Bangladesh

1. Approach to anaemia Dr. Md. Shamim Akhter Registrar ,Internal Medicine,SZMCH

2. Definition Anaemia refers to a state in which the level of haemoglobin in the blood is below the reference range appropriate for age and sex .

3. Causes A) Blood loss--- acute and chronic B) Impaired red cell production--- Iron deficiency Vit-B12 deficiency FA deficiency Protein malnutrition Aplastic anaemia Thalassaemia Hypothyroidism Anaemia of chronic disorders- Anaemia due to marrow infiltration-

4. Anaemia of chronic disorders- Chronic infection-TB CKD Connective tissue diseases-RA,SLE Chronic inflammatory disorders Disseminated malignancy Anaemia due to marrow infiltration- Leukaemia Lymphoma Myeloma Myeloproliferative disorders Myelodysplastic disorder

5. C) Excessive red cells destruction- Haemolytic anaemias --- Red cell membrane defect (e.g. hereditary spherocytosis , eliptocytosis , stomatocytosis ), Haemoglobinopathies Autoimmune haemolytic anaemia infectious causes-malaria Microangiopathic hemolytic anemia-DIC,HUS,TTP Enzyme defects Hypersplenism ---

6. Morphological (depending on MCV and MCHC) Normocytic normochromic anemia normal MCV ,MCH and MCHC 2. Microcytic hypochromic anemia low MCV, low MCH, MCHC 3. Macrocytic normochromic anemia high MCV, normal MCH,MCHC

7. Normocytic normochromic an a emia s are--- Acute blood loss anaemia Aplastic anaemia Anaemia of chronic disorders Anaemia due to marrow infiltration Microcytic hypochromic anaemias are--- Iron deficiency anaemia Thalassaemias Sideroblastic anaemia Anaemia of chronic disorders(after long time)  

8. thalassaemia minor/trait— Low MCV,MCH, normal or marginally low MCHC thalassaemia major— Low MCV,MCH, mildly reduced MCHC Diamorphic anemia (two cell lines— macrocytes and microcytes — sideroblastic , thalassaemia major acute haemolysis,acute blood loss— normocytes+macrocytes

9. Macrocytic normochromic anemia--- Macrocytic megaloblastic - Vit-B12 deficiency FA deficiency Macrocytic normoblastic - Hypothyroidism Liver disease Alcoholism Pernicious anaemia Drugs- Previous abdominal (stomach/small bowel) surgery Hyperlipidaemia pregnancy

10. Clinical evaluation History Symptoms--- Tiredness,fatigue Lightheadedness Breathlessness Development/worsening of ischaemic symptoms, e.g. angina or claudication Effort intolerance Effort dyspnoea palpitations

11. Queries History of bleeding– hemorrhoid, hematemesis,melaena , menorrhagia in female. Note-chronic haematuria and haemoptysis very rarely causes iron deficiency, negetive history does not Exclude bleeding ,because GIT bleeding may be occult. Dietary history-- to diagnose deficiency anemia like iron, vitamin B12 and folic acid deficiency). History of multiple pregnancies, repeated abortion in females

12. Drug history— NSAIDs, steroid, drugs causing bone marrow suppression (e.g. cytotoxic drugs), drugs causing hemolysis ( sulfasalazine , methyldopa ). History of surgery— gastrectomy , ileal surgery (iron and/or vitamin B 12 absorption). Family history of anaemia (in case hereditary hemolytic anemia). History of any chronic disease (e.g. SLE, CRF,RA, TB,malignancy,liver disease,endocrine disease ).

13. Age- during reproductive age of female (menstruation, pregnancy, parturition,breast feeding), rapid growth during infancy and puberty History of malabsorption,alcohol intake

14. Examination General physical- • pallor • Tachycardia • Ankle oedema temperature- leukaemia,lymphoma Face- Frontal,parietal bossing( haemolytic facis ) Jaundice- haemolytic HTN-CKD Koilonychia -IDA Bony tenderness- leukaemia,MM Raised jugular venous pressure(CCF) Leg ulcer( Hb S)

15. Systemic- CVS- • Flow murmurs • Postural hypotension Alimentary system- Angular stomatitis -IDA Glossitis ( depapillation )-IDA,vit-B12 deficiency smooth raw beef tongue—B12 smooth --IDA hepatosplenomegaly-HHA,leukaemia,lymphoma,kalazar,malaria Nervous system- Peripheral neuropathy(gloves and stocking)loss of ankle jerk,dementia,optic atrophy-(Vit-B12 deficiency) Features of subacute combined degeneration of spinal cord(Vit-B12 deficiency)

16. Quick decision making from history and examination- Anemia with HTN,edema ---think CRF Anemia with fever ---think aplastic anemia / leukaemia / Kala- azar / lymphoma/MM Anemia with bleeding manifestation ----think aplastic anemia / leukemia anemia with weight loss & anorexia ---think Malignancy anemia with organomelagy -- leukaemia,Lymphoma,Thalassaemia,Kala-azar,malaria , TB,CLD

17. Some information about different anaemia Acute blood loss anemia--- anaemia occur after 48-72 hours ,after haemodilution No immediate reticulocytes in PBF because time required for EPO production Chronic blood loss anaemia --- Anaemia due to iron deficiency Acute haemolysis --- Red cell indices--- normocytic to macrocytic due to increased reticulocytes

18. Iron deficiency anaemia—anaemia due to low Hb production 3 stage findinds — Negetive iron balance— S. Ferritin <20 RBC— normochromic normocytic Iron deficient erythropoiesis --- S. Ferritin <15 RBC— normochromic normocytic marrow is hypoproliferative Iron deficiency anaemia --- s. Ferritin <15 RBC- hypochromic microcytic marrow is hyperproliferative but low RPI

19. Thalassaemia trait/minor--- Mild or no anaemia,high RBC count,normal MCHC(or at lower margin) Thalassaemia major--- Anaemia due to low Hb content and extravascular haemolysis Hypothyroidism--- Liver disease--- ACD--- Normochromic normocytic , but after prolonged time mild microcytic hypochromic . Anaemia due to suppressed EPO activity,short RBC life,impaired Iron utilization

20. Laboratory evaluation General investigations- 1. Hb%,TC,DC,ESR,TPC 2. PBF examination 3. HCT/PCV 4. Red cell count 4. Red cell indices-MCV ,MCH and MCHC,RDW 6. Reticulocyte count

21. Special investigations- Iron profile-serum iron, serum ferritin , TIBC, transferrin saturation Hb electrophoresis Coombs test Bone marrow examination Serum B12 ,FA assay Occult blood test Endoscopy of upper GIT, colonoscopy Tests to support haemolysis

22. Details about interpretation of investigations Hb % Mild anaemia - below lower limit of normal range Moderate anaemia - <10 gm/dl Severe anaemia - <7 gm/dl

23. Peripheral blood film Anisocytosis - variation in size of RBC Iron deficiency anemia, megaloblastic anemia Macro/ microcytic anaemia after BT Poikilocytosis - Variation in shape of RBC Iron deficiency anemia, megaloblastic anemia thalassemia ,

24. Microcytosis -- Iron deficiency anemia, thalassemia , anemia of chronic disorder sideroblastic anemia, Macrocytosis -- Vitamin B12 and folic acid deficiency, chronic liver disease, alcohol hypothyroidism

25. Polychromasia –high reticulocytes count Hemolysis , acute hemorrhage, increased red cell turnover Nucleated RBC( Normoblasts )--- Bone marrow infiltration, Severe hemolysis , Acute hemorrhage

26. Schistocytes ( Fragmented RBC)--- found in microangiopathic hemolytic anemia Causes—DIC, HUS, TTP, disseminated carcinomatosis , Malignant hypertension PIH- eclampsia Spherocytes (Small RBC with loss of central pallor)- Hereditary spherocytosis , autoimmune hemolytic anemia, post- splenectomy

27. Target cells – central mass of hemoglobin surrounded by a ring of pallor (pale area) and an outer ring of hemoglobin Iron deficiency anemia, thalassemia , CLD,post - splenectomy Tear drop cell--- Myelofibrosis,thalassaemia Hypersegmented neutrophil- megaloblastic anaemia Pencil shaped cell,elongated cells--- IDA Sickle cell--- SCA

28. Red cell indices- MCV- volume of a RBC Interpretations are- microcytic / normocytic / macrocytic MCH-amount of Hb in a RBC MCHC- concentration of Hb in a RBC(MCH/MCV) Interpretations of both are- hypochromic / normochromic Red cell distribution width(RDW)

29. Red cell distribution width(RDW) RDW -measures the variation of red cell size( anisocytosis ) normal =12-17%. Importance--It hepls to differentiate the causes of microcytosis . RDW increased in(causes of anisocytosis )— iron deficiency anemia(moderate to severe ) Megaloblastic anaemia Thalassaemia patients after BT RDW normal in--- thalassemia anemia of chronic disease (ACD)

30. Reticulocyte count Indicates-- bone marrow response in the face of anemia. Normal= 0.5-2.5% Count increase in anaemic patients when— haemolysis , Haemorrhage with adequate iron stores During treatment with iron,Vit-B12,FA Count decrease in anaemic patient when- Marrow hypoplasia

31. Reticulocyte production index (RPI)- Purpose- to see marrow response in face of established anaemia RPI in non- anaemic patients = 1 High RPI(>2) indicates --bone marrow erythroid hyperplasia that is effective marrow response to anaemia low RPI(<2) means- - marrow failure / hypoplasia . RPI confirms the fact that the patient – has an appropriate EPO response, normally functioning bone marrow, and sufficient iron available to meet the demands for new red cell formation

32. RPI calculation- Correction #1 for Anemia: corrected(absolute) reticulocyte count= Example- Reticulocytes count in blood report=9% Patients current Hb =7.5 gm/dl --------------------------------------------------------- So corrected reticulocytes count=4.5%

33. RPI >2 in- Hemolytic anaemias Acute Hemorrhage RPI <2 in- Hypochromic microcytic anaemias - IDA Thalassaemia Sideroblastic anaemia ACD Macrocytic anaemias - Vit-B12 and FA deficiency Some Normochromic normocytic anaemias - Aplastic anaemia Marrow fibrosis Marrow infiltration

34. Correction #2 for Longer Life of Prematurely Released Reticulocytes in the Blood : When needed?-Correction 2 is needed when there is very high reticulocytes count( polychromasia ) RPI = Hct Correction factor 45 1 35 1.5 25 2 15 2.5

35. Red cell count- It can be normal in some patients with anaemia based on Hb %- IDA Thalassaemia minor

36. Iron profile-serum iron, serum ferritin , TIBC Serum Iron and TIBC is a direct measure of the protein transferrin and iron availibility Transferrin transports iron from the gut to iron storage sites in bone marrow. it is also called acute-phase reactant—that is, its serum levels change (usually decrease, so-called “negative acute phase reactant”) in inflammatory conditions

37. Serum Ferritin serum ferritin levels give an excellent measure of storage iron(total). Best single test to confirm iron deficiency in ACD- iron stores are abundant, serum ferritin levels are characteristically normal to elevated. in IDA- iron stores become depleted, serum ferritin levels are characteristically decreased In Thalassaemia,sideroblastic a. — normal to elevated

38. ***A serum ferritin level of <15 μg /L indicates depletion of body iron stores ***As a rule, a serum ferritin >200 μg /L means there is at least some iron in tissue stores Problem with s. ferritin - 1. It is an acute phase reactant so, rise in acute process (infection or inflammation) ,liver disease, and chronic inflammation (RA) also. Usually, in IDA, accompanied by above conditions ferritin level below 100 microgram/L considered as low iron stores 2. a normal value does not reliably exclude iron deficiency

39. T-sat( transferrin saturation) Measure of- transferrin bound irons more reliable than s. iron and TIBC In differentiating IDA and ACD but less specific than ferritin level This is 25-50%(average30%) for normal individuals, In IDA- --it is significantly reduced below 16% In ACD--- decrease or normal(de Gruchy ) decrease( davidson ) Thalassaemia,sideroblastic anemia- --normal

40. Hb electrophoresis Interpretations- Normal person- Hb A -97% Hb-A2 -1.5%-3.2% Hb F -0.5%-1% No Hb -S, Hb -E Beta Thalassaemia major (homozygote state)— Hb -A -absent Hb A2 – low Hb F is more Beta thalassaemia minor/ trait (heterozygote state)- Hb -A – mild decreased Hb A2 – mild increased Hb F - variable Alpha thalassaemia trait- Hb A , , Hb F -- all are low Hb-A2--normal Hb -H disease- Hb -H present

41. Hb - E disease (homozygote state)– Hb -E is present but Hb E > Hb A Hb - E trait (heterozygote state)– Hb -E is present but Hb E < Hb A Hb -S disease(sickle cell disease/ anaemia—homozygotes state)- Hb -S Present Hb F present but No Hb A Hb -S trait(sickle cell trait—heterozygote state) - Hb -S Present but, Hb S < Hb A

42. Beta thalassaemia - Hb -E disease

43. Bone marrow study Required in patients with normal iron status with hypoproliferative (low RC,normochromic normocytic ) anaemias - Aplastic anaemia Marrow infiltration Macrocytic anaemia

44. Coombs test

45. Occult blood test

46. Stepwise Quick decision making from investigations First see MCV ,MCH,MCHC and decide whether it is Microcytic hypochromic / normchromic / normocytic / macrocytic normochromic ?

47. Microcytic hypochromic See RDW --- consider thalassaemia trait if--- Normal RDW,MCHC(or marginally reduced) with high RBC count,mild anaemia (>10) consider ACD(late stage) if--- Normal RDW with decreased RBC count, mild to moderate anaemia consider IDA if--- Increased RDW Now do S. ferritin — ACD-- -normal or elevated  if Hb <8 gm/dl do BMS thalassaemia trait- -- normal  do Hb electrophoresis to confirm IDA- --low

48. See reticulocytes count/RPI--- If high-– consider homozygous thalassaemia ,abnormal Hb  do Hb electrophoresis to confirm If low ---consider IDA,ACD,siderblastic anaemia See PBF--- Target cells---consider thalassaemia Dimorphic----consider sideroblastic anaemia  do bone marrow study to confirm

49. Normocytic Normochromic Fisrt see reticulocytes count/RPI--- Increased RC/RPI- --consider acute blood loss , haemolytic anaemias (other than thalassaemia ) Normal/decreased RC(RPI)--- consider ACD or marrow failure or due to aplastic anaemia,marrow ifiltration , fibrosis,MDS .

50. Macrocytic normochromic First see reticulocytes count--- If high( polychromasia )—consider acute bleeding or haemolytic anaemias  do tests to support haemolysis If normal/low—consider megaloblastic anaemia,hypothyroidism,liver disease,alcohol,MDS See PBF--- Megaloblastic -- Hypersegmented neutrophil,poikilocytosis do vit-B12/FA assay to establish,BMS to confirm Liver disease—target cells Sideroblastic --- Dimorphic do BMS