Pathophysiology of anemias geral concepts.pptx

ANEMIAS OVERVIEW

1. Pathophysiology of anemias. Block 4.1-2024 1

2. Anaemia is a reduction of the normal Hb concentration (g/dl). It doesn´t depend of number of red blood cells ! Normal Hb values : Man: 13 g/dl Woman: 12 g/dl Pregnant woman : 11 g/dl ( because hypervolemia ) Child: 12 g/dl 2

3. α chain β chain heme HEMOGLOBIN ferro 3

4. 4

5. The human body lacks a physiological iron elimination mechanism, so that the regulation of its intestinal (duodenal) absorption is crucial to the formation of red blood cells. Iron balance is physiologically regulated by controlling iron absorption; iron stores, erythropoiesis and absorption are reciprocally related, so that as stores decline or erythropoietic activity increases, absorpion increases. 5

6. 6 After 120 days, the erythrocytes are destroyed by the macrophages of the phagocytic mononuclear system (mainly spleen, liver and bone marrow), releasing the Fe ++ from the inside. Some of erythroid marrow iron arrives at macrophages more directly, because of phagocytosis of defective precursors or removal of erythrocyte ferritin. An important part is stored in the macrophages in the form of ferritine and hemosiderin . The rest is oxidised again to Fe +++ , crosses the macrophage membrane and binds to the plasma transferrin to close the circle and return to the medullary erythroblast. This recycling route is indispensable because only 1-2 mg of the 20 mg daily of iron needed for the formation of haemoglobin is new, coming from food, so that the rest has to be recycled from the hemocateresis .

7. IRON METABOLISM erythroid precursors in bone marrow Circulating erythrocytes Liver Iron in plasmatic trasferrin desquamation, loss of blood 1-2 mg / day Skin , gut , endometrium Intestinal absorption Deposits in mononuclear phagocytes 7

8. 8 Iron metabolism Armazenamento: – Ferritina - complexo proteína-ferro hidrosolúvel . 30% do seu peso de ferro. – Hemossiderina – insolúvel, presente nos lisossomos, com 33% das reservas de ferro. Local - Macrófagos no fígado e baço e na medula óssea, hepatócitos , músculos, mucosa do trato gastrointestinal ( ferritina ) e no plasma ( ferritina ).

9. The most common microcytic anemias are: ferropenic anemia : shortage (iron deficiency) gynaecological chronic anaemia digestive haemorrhage ( lesions of GI tract, GI mucosal damage by drugs, infections) skin loss (scaly diseases of chronic evolution) bad dietary iron absorption ( gastrectomy , steatorrhea , rapid intestinal transit) 9

10. 10 Erythron: all erythroid elements, including cells at all stage of development, in the marrow, circulation and extravascular espace.

11. Microcitical Iron deficiency Anemia According to iron deposits: 1º) PRELATENT IRON DEFICIENCY :  of reserve iron with sideroblasts (<5%) and ferritin , and sideraemia normal. 2º) LATENT IRON DEFICIENCY ERYTHROPOIESIS : sideraemia  , transferrin saturation   , ferritin   , moderate microcytosis and hypochromia but with practically normal (no anaemia) haemoglobin. 3º) IRON DEFICIENCY ANAEMIA : anaemia with all erythrocyte and iron kinetics indices altered  clinically manifest anaemia: Hb , ( microcytic anaemia ), ferritin    . 11

12. CLINIC of anaemia: dyspnoea, fatigue, pale skin and mucosa, dizziness, tachycardia, murmur cardiac valves... Anemia, like the sedimentation rate, is thus often a “sickness index” of the body: the challenge is to recognize the underlying pathology. 12

13. 1. Haemogram : Hb , VCM, HCM and RDW ( R ed blood cell D istribution W idth ) 2. Study of Fe metabolism: - sideremia - transferrin / transferrin saturation - ferritine - Reticulocitary Hb 3. Blood smear 4. Bone marrow aspirate 13 Laboratory of Iron alterations

14. Objetivos do tratamento: corrigir a anemia, reconhecer e atuar na causa da deficiência. • Medicamentos a base de íon ferroso e férrico. • Via Oral : – Em adultos, a forma ferrosa (sulfato, gluconato, fumarato) é a mais usada(200mg/dia 3x ao dia) – Em crianças menores de 15kg, a forma líquida é mais usada. – Sais férricos são usados com maiores doses e tem menos efeitos colaterais . – Uso por 1-2 meses. Via parenteral : – Uso na intolerância oral de ferro, com azia, diarréia , colites ulcerosas, colostomias , gastrectomias. – IM – ferro polimaltosado . EV – ferro sacaratado . • Prevenção: indicada a crianças amamentadas inadequadamente, em mulheres durante os 2 últimos trimestres gravidez (15-30mg de ferro/dia). 14

15. Anemia can be caused by : a primary hematologic disorder within the marrow Decreased production an accelerated loss Increased Distruction a destruction of RBCs in the periphery . Blood Loss In some circumstances, several factors converge to produce anemia: multifactorial anemia. 15

16. 16

17. 17

18. 18

19. Morphological criteria ( MCV ), according to erythrocyte size : Normocytic anaemia: MCV = 80-98 fl Microcytic anaemia: MCV < 80 fl Macrocytic anaemia: MCV > 98 fl Reticulocytaemia , according to medullary response : Regenerative (increment reticulocytes ) Aregenerative (low reticulocytes ) Classification of anemias, according to: 19

20. 20

21. The most common anemias are microcytic anemias . These anemias are characterised by a deficit of Hb synthesis: ferropenic anemia : shortage (iron deficiency) “ inflamatory anemia ” or “iron bone marrow blockage” : blockage and poor use of iron deposits. thalassaemias deficit in globine synthesis sideroblastic anaemia deficit in heme synthesis 21

22. Differential diagnosis : Iron deficiency anaemia :  MCV ,  MCH, Fe  , Hb  , serum Ferritin  Thalassaemia :  MCV ,  MCH, Fe: N, Hb  , serum F erritin  Inflammatory anaemia : MCV and MCH usually N ,  Fe, serum Ferritin  ,  Macrophage Fe and  sideroblasts very poor in Fe. 22

23. 23

24. 24

25. 25

26. 26 Thank you for your attention .