2. Hematopoiesis
• Hematopoiesis is the process by which mature blood cells are generated
and functional, assuming the existence of cells of origin who have a long
series of transformations and hematopoetic microenvironment
(composed of stromal cells and stimulating factors).
• Bone marrow (BM) is the central component generating blood cells: red
cells, granulocytes, monocytes, lymphocytes, platelets and hematopoietic
functions are proliferation, differentiation and cell release into circulation.
• BM consists of:
– reticulovascular stroma (with supporting role, nutrition and
movement of hematopoietic cells);
– medullar parenchyma - composed of active cells forming islands of
hematopoiesis, usually arranged around a trophic cell - "nurse cell."
Nurse cells are involved in erythropoiesis (iron stores) in myelopoesis
and megacaryopoesis (liberate stimulating factors - e.g.. IL-3).
4. Anemic syndrome
• Definition
– Anemic syndrome is defined as a poly-etiologic syndrome
characterized by decrease in circulating hemoglobin (Hb) below the
normal values.
5. Anemic syndrome
Adults (>15 years)
Hb (g/dl) Hb (mmol/l)
Women 12.0 7.4
Men 13.0 8.1
Children
Hb (g/dl) Hb (mmol/l)
Children < 5 years 11.0 7,1
Children < 15 years 12.0 7.4
6. Signs and symptoms
• Presence of a history of bleeding (not in all cases)
• Dyspnea (initial effort)
• Pallor
• Dizziness
• Low grade fever
• Compensatory hemodynamic syndrome
– Tachycardia
– Murmurs
– Palpitations
– Low blood pressure
7. Signs and symptoms
• Ventilatory changes
– Polipnea
• Changes in the peripheral nervous system's activity caused by neuronal
hypoxia:
– Paresthesia
– Neurovegetative dystonia
– Changes of reflexes
– Positive Babinski sign
– Ataxia
– Sphincter incontinence
– Changes of the senses
9. Signs and symptoms
• Trophic disorders of the mucous membranes
– Glossitis
– Esophagitis
– Gastritis
– Dyspepsia
• Trophic disorders of the skin and appendages
– Brittle hair
– Digital hypocratism (hippocratic fingers)
– Pigmentation of the skin
– Leg ulcers
• Bone pain
10. Classification
• A. Anemia caused by decreased production of red blood cells
• B. Anemia caused by lost of red blood cells
• C. Anemia caused by combined mechanisms
11. A. Anemia caused by decreased production of red
blood cells
• 1. Involvement of hematogenous bone marrow (BM):
– a. Destructive processes:
• Physical factors: ionizing radiation
• Chemical factors: drugs (cytostatics, anti-inflammatory -
phenylbutazone, chloramphenicol, phenytoin), industrial -
benzene, insecticides;
• Biological factors: some viruses (Epstein - Barr virus, hepatitis C,
parvovirus infection, human immunodeficiency virus);
• Immune diseases: timom, graft versus host reaction, eosinophilic
fasciitis;
• Unknown etiology
12. A. Anemia caused by decreased production of red
blood cells
• 1. Involvement of hematogenous bone marrow (BM):
– b. Bone marrow infiltrative processes:
• Tumours of the bone marrow (BM): leukemia, lymphoma, multiple
myeloma (MM)
• Metastases in BM
• Sarcoidosis
• Bone marrow fibrosis
• Storage diseases (glicogenoze, lipidosis - Gaucher disease)
• Bone marrow necrosis
• Bone marrow infections: sepsis, miliary tuberculosis, fungal
infections
13. A. Anemia caused by decreased production of red
blood cells
• 1. Involvement of hematogenous bone marrow (BM):
– c. Low production of erythropoietin:
• Anemia of chronic disease (chronic inflammation, chronic
infections, cancers) - inflammatory cytokines (IL1, IL 6, TNF-α) - suppresses the
synthesis of erythropoietin and erythropoietin increases resistance to the action;
• Kidney disease - chronic renal insufficiency - insufficient production of
erythropoietin due to renal lesions;
• Liver disease - by parenchymal liver failure (cirrhosis, hepa-tice,
toxic hepatitis, chronic aggressive hepatitis, etc.) - It reduces the
synthesis of erythropoietin and hemoglobin precursors;
• Poliglandular hypofunction - production of erythrocytes is
influenced by thyroid hormones, testosterone, glucocorticoids.
14. A. Anemia caused by decreased production of red
blood cells
• 2. Deficiency of forming factors:
– a. Protein deficiency:
• Low protein intake
– Malnutrition - starvation, low protein in food;
– Maldigestion - exocrine pancreatic insufficiency, bile salt
deficiency, gastrectomy;
– Malabsorption - intestinal resection, bacterial diarrheal
diseases, viral (excluding the time of contact of food with
intestinal mucosa), intestinal parasites;
• The reduced synthesis of proteins - parenchymal liver
insufficiency;
• The additional consumption of protein - "trap" of protein in end-
stage of cancer;
• Increased protein loss - diarrheal diseases, burns, nephrotic
syndrome;
15. A. Anemia caused by decreased production of red
blood cells
• 2. Deficiency of forming factors:
– b. Lack of synthesis of purine and pyrimidine derivatives (nucleic acids,
macroergic phosphates)
• Lack of vitamin B12
• Lack of folic acid (B9)
• Other vitamin deficiencies - deficiency of fat soluble vitamins (A, D,
K, E, F), lack of water-soluble vitamins - B thiamine (B1), riboflavin
(B2), niacin (B3), pirodoxina (B6), pantothenic acid (B5), biotin
(B7);
– c. Caused by iron deficiency anemia (iron deficiency anemia)
• Loss of blood
• Low intake
• Increased needs
• Iron metabolism disorders
16. B. Anemia caused by lost of red blood cell mass
• 1. Bleeding or iatrogenic emissions of blood
• 2. Increased destruction of erythrocytes - hemolytic syndrome (prehepatic
jaundice)
– a. Extracorpusculare causes:
• Physical factors
– Mechanical
» Mechanical cardiac causes hemolytic anemia (acquired or
congenital) - aortic stenosis, coarctation of the aorta,
mitral insufficiency, aortic aneurysm, heart valves;
– Thermal – heat
– Ultrasound
– Radiation - ultraviolet (photodermatosis), high-energy ionizing
radiation;
17. B. Anemia caused by lost of red blood cell mass
• 2. Increased destruction of erythrocytes - hemolytic syndrome (prehepatic
jaundice)
– a. Extracorpusculare causes:
• Chemical factors
– Exogenous - arsenic, copper, lead, etc..
– Endogenous - hemolytic anemia in nitrogen retention (renal
failure);
• Biological factors
– Parasites - Malaria (Plasmodium falciparum), babesiosis
(Babesia genus)
– Bacteria - bacterial toxins (Clostridium, E. Coli, Streptococci)
– Viruses (Epstein Bar, herpes encephalitis virus);
– Toxic - venoms (snake, scorpion, spider)
18. B. Anemia caused by lost of red blood cell mass
• 2. Increased destruction of erythrocytes - hemolytic syndrome (prehepatic
jaundice)
– a. Extracorpusculare causes:
• Autoimmune hemolytic anemia
• Hypersplenism
– Removal of damaged erythrocytes
– Response to bacterial, viral, parasitic
– Autoimmune diseases
– Metabolic diseases
– Tumors
• Hemolytic anemia with combined mechanisms - vascular
coagulation (DIC)
– DIC is a clinical syndrome (infections, cancers, venoms, autoimmune diseases,
trauma, burns, etc. obsterticale cases.) characterized by intravascular
coagulation, with the formation of thrombosis and necrosis, accompanied by
secondary fibrinolysis and consumption of coagulation factors, with bleeding.
19. B. Anemia caused by lost of red blood cell mass
• 2. Increased destruction of erythrocytes - hemolytic syndrome (prehepatic
jaundice)
– b. Corpuscular causes:
• Metabolic - enzyme deficiency:
– At the level of glycolysis - glucose 6-phosphate dehydrogenase
(G6PDH) deficiency, pyruvate kinase deficiency, etc.
– In the cycle of glutathione - glutathione synthetase deficiency,
glutathione reductase deficiency;
– Lack of heme synthesis (porphyrias)
– Lack of globin synthesis (globinopathies)
– Lack of hemoglobin synthesis (hemoglobinopathies)
20. Complications of anemic syndrome
• Decreased Hb reduces oxygen to tissues with consequent hypoxia.
• The effct of hypoxia depends on cells needs (neurons and muscle cells
have greater needs) and on cell proliferation rate.
21. Complications of anemic syndrome
• Biochemical changes:
– Krebs cycle activity is reduced due to low oxygen. Following, the
synthesis of macroergic phosphates (plastic and energetic role) is
reduced.
– Reduced Warburg respiratory chain activity with reduced heat
production.
– Increased glycolitic activity with accumulation of non-volatile organic
acids (lactic acid, pyruvic acid) flattens the hemoglobin dissociation
curve (oxygen is released more easily to the tissue).
– Reduced liver metabolism.
22. Complications of anemic syndrome
• Hemodynamic changes:
– Preferential redistribution of blood flow to vital organs
(catecholamines causes vasoconstriction in the splanhnic and skin
territory) - skin blood flow reduction causes - pallor, decreased skin
temperature, feeling cold, shivering, trophic skin changes. Onset of
symptoms depends on the magnitude and duration of the anemic
syndrome.
– Hemodynamic compensatory hyperkinesia evidenced by: tachycardia,
increased blood flow, increased blood speed, murmurs, increased
circulatory flow.
– Hyperkinetic compensation increases oxygen consumption which, in
time, will lead to cardiac decompensation (dyspnea, swelling,
transudates, etc.)
• If there is a preexiting coronary obstruction, anemia and
compensatory tachycardia, may lead to angina or increased
frequency of its manifestation, instable angina or even myocardial
infarction.
23. Complications of anemic syndrome
• Respiratory changes
– Compensatory polipnea
• Renal changes
– Hypoxia stimulates production of erythropoietin
• Through hypoxia - induced transcription factor 1 * (HIF -1).
– Hypoxia stimulates renal renin → activates the renin - angiotensin -
aldosterone system → retention of sodium (electrolyte imbalance).
24. Complications of anemic syndrome
• Alteration of tissue perfusion:
– Vasomotor activity and angiogenesis are modiffied.
• Promotion of angiogenesis is through vascular - endothelial
growth factor - (VEGF).
– Changes in skin and mucous membranes (tissues with increased cell
turn-over):
• Glossitis, esophagitis, gastritis, bronchitis, vulvovaginitis
• Leg ulcers
• Pigmentation
– Changes to appendages
• Brittle hair, digital hipocratism
25. Complications of anemic syndrome
• Increased production of red blood cells
– Stimulation of erythropoietin encoding gene via hypoxia-induced
transcription factor (HIF-1), results in increased synthesis of
erythropoietin.
• * HIF-1 functions as a regulator of adaptive responses induced by
hypoxia. Under conditions of hypoxia it activates transcription of
over 40 genes, including those responsible for synthesis
erythropoietin, glucose transporters, glycolitic enzymes, vascular -
endothelial growth factor (VEGF) and other proteins that facilitate
metabolic adaptation to hypoxia.
– Increasing production of red blood cells is mediated by erythropoietin.
Rates of synthesis of erythropoietin is in inverse relationship with Hb
concentration. Erythropoietin concentration can increase 1000 times
in severe anemia.
– It enhances erythropoiesis, with expandation of erythropoietic tissue,
possibly with sternal pain or diffuse bone pain.
26. Complications of anemic syndrome
• Immune system abnormalities:
– Hipoxia lowers the defense capacity of the immune system, especially
related to protection of mucosas;
– Anemic patient is prone to infections;
• Endocrine changes:
– Pituitary hypofunction
– Thyroid hypofunction
– Gonadal hypofunction
• Changes in menstrual cycle
• Amenorrhoea
• Impotence
27. Particular form of anemia - Iron deficiency anemia
• Iron deficiency is the most common cause of anemia.
• 20% of women (50% of pregnant women) and 3% of men do not have
enough iron in the body.
• Disruption of iron metabolism causes anemia and disturb cytochromes
activity (cell respiration).
• Iron is obtained through dietary intake (muscle, liver) and iron absorption
requires the presence of HCl and transferrin.
28. Iron deficiency anemia - causes
• Loss of blood:
– Bleeding
• Menstrual loss
– Frequent blood emission
• Polycythemia vera (PV) –
therapy
• Blood donors
– Neoplasms
• Inadequate intake:
– Vegetarian diet
– Global malabsorption / selective
for iron
• Aclorhydria
• Resected stomach
• Celiac disease
• Parasitosis
• Iron metabolism disorders
– Lack of transferrin
• Congenital
• Hepatic
• Nephrotic syndrome
– Defective / deficient transferrin
receptors
• Increased needs: pregnancy,
lactation, gemelarity, prematurity,
sports performance
30. Laboratory data
• Low Hb
• Normal or low number of reticulocytes
• Low sideremia
• Increased total iron binding capacity
• Elevated transferrin
• Low ferritin
• Absent iron reserves in the bone marrow (Perls staining)
• Blood smear
– Microcytosis
– Hypochromia
– Pokylocitosis
• CBC
– Low Hb, MCV ↓, MCH ↓, MCHC ↓
– WBC count normal or slightly decreased
– Frequently thrombocytosis
• Bone marrow
• Red series hyperplasia with iron deficiency erythroblasts
33. Anemia of chronic disease
• It is a normochromic, normocytic or hypochromic, microcytic anemia,
which develops through multiple mechanisms.
• Newest name, inflammation associated anemia, is more representative
because it reflects pathophysiological mechanisms.
• It secondary appears in:
– Chronic inflammation (infections, tuberculosis, endocarditis,
abscesses);
– Collagen diseases (SLE, RA, SS);
– Malignancy (carcinoma, multiple myeloma, lymphoma)
– Elderly anemia.
34. Pathogenesis
• This type of anemia is characterized by the inability of the body to increase red
cell production, to compensate for red cell destructions more or less
increased.
• Sustained stimulation of monocytic-macrophage system because of chronic
inflammation, autoimmune diseases or tumors, decrease life of erythrocytes
by increasing phagocytosis.
• During inflammation, iron releasing from macrophages and liver deposits is
significantly inhibited.
– Interleukin 6 (IL-6) produced during inflammation induces the synthesis of
hepcidine (iron regulating hormone), which in turn inhibits iron release from
macrophages and hepatocytes, with consequent decreasing sideremia.
• Hepcidine binds the feroportin molecules from the membrane, molecules
responsible for iron export, leading to their internalization and intracellular
degradation. In this way iron stuck in macrophages and can not be used for Hb
synthesis.
– It is known that iron is incorporated into protoporphyrin IX and zinc may substitute
iron for its synthesis.
35. Pathogenesis
• Another mechanism mediated through inflammation mediators (IL-1,
interferon alpha) is low compensation capacity through erythropoietin by
decreasing its synthesis.
• Finally there is a decreased iron in serum and erythrocyte precursors, with
increased reserves of iron. The lifespan of red blood cells decreases
without adequate compensation.
• Inflammatory cytokines promote the production of white blood cells.
36. Other anemia with low erythropoietin
• Kidney disease - chronic renal insufficiency - insufficient production of
erythropoietin due to renal lesions;
• Liver disease - by parenchymal liver failure (cirrhosis, toxic hepatitis,
chronic aggressive hepatitis, etc.) - It reduces the synthesis of
erythropoietin and hemoglobin precursors;
• Poliglandular hypofunction - production of erythrocytes is influenced by
thyroid hormones, testosterone, glucocorticoids.
37. Laboratory data
• Low Hb;
• Low number of reticulocytes;
• Low sideremia;
• Low total iron binding capacity;
• Increased ferritin;
• Perls staining of bone marrow shows reduced number of syderoblast and a
high amount of hemosiderine in the macrophages.
38. Megaloblastic anemia
• Anemia is normochromic, macrocytic defined by increasing MCV over 100
fl.
• Macrocytosis is typical in:
– Megaloblastic anemia
– Alcoholism
– Liver disease
• Megaloblastic anemia is characterized by nucleo-cytoplasmic asincronism
due to deficiency in DNA synthesis with normal RNA and protein synthesis
(immature nuclei and mature cytoplasm).
• The most common cause is vitamin B12 deficiency and / or folic acid
deficiency.
• A common cause of B12 deficiency is Biermer anemia. It is believed that
the mechanism is immune, mediated by antibodies to intrinsic factor (IF)
or / and anti gastric parietal cells. Thus vitamin B12 absorption disorder is
secondary to lack of IF.
39. Megaloblastic anemia
• Folic acid:
– It is found in fresh vegetable products, liver;
– The daily necessary amount is about 100 mg, normal diet providing
much more than this amount;
– The total reserve is up to 5 mg, enough for 3-4 months;
– Normal serum level is - 5 to 20 ng / ml;
– It is absorbed in the proximal jejunum;
• Vitamin B12:
– Food sources are animal products;
– B12 absorption occurs in the terminal ileum;
– The daily necessary is 1μg;
– B12 liver reserves are sufficient for 3-5 years;
– Serum B12 level is 200-600 pg / ml;
– Absorption is only in the presence of intrinsic factor (IF), glycoprotein
produced by gastric parietal cells.
40. Causes of B12 deficiency
• Deficient intake (malnutrition, vegetarian);
• Malabsorption:
– Inadequate production of IF (pernicious anemia), gastrectomy,
congenital deficiency;
– A disease of the terminal ileum: celiakie, Crohn's disease, intestinal
resection, intestinal neoplasms, selective malabsorption of B12;
– An intestinal consumption of B12: parasites, bacteria
– Drugs that interfere with B12 absorption: neomycin
• Deficiency in transportation and use of B12 : congenital deficiency of
transcobalamin II (TC), excess of I and III TC, enzyme deficiency.
43. Laboratory data
• Low Hb
• Low / normal number of reticulocytes
• CBC
– MCV > 100 fl
– Leucopenia
– Moderate thrombocytopenia
• Blood smear
– Macrocytosis (macrocytic anemia) , macro-ovalocytes, megalocytes
– Hypersegmented neutrophils (from 5 lobes)
• Bone marrow
– Hyperplasia, predominantly in red blood cells with asincronism in
maturation of the hematopoetic precursors
44. Laboratory data
• Biochemistry:
– Low serum cobalamin <100 pg / ml
– Increased level of intrinsic factor antibodies and anti-parietal cells
– Increased lactate dehydrogenase
– Increased or normal serum iron
– Schilling test positive - no excretion of radiolabelled B12
– Atrophy of gastric mucosa at endoscopy