18 Approach to Patients with Anemia Flashcards
Process by which the formed elements of blood are produced
Hematopoiesis
Two main hematopoietic lineages
Common myeloid progenitor
Common lymphoid progenitor
Main regulatory hormone of red cell production which is produced in the kidney
EPO
Stimulus for EPO production
Low atmospheric oxygen level
Tissue hypoxia
Living in high altitudes
Cardiovascular failure
Decrease in hemoglobin
Often recognized with lab test after px present with s/s
Anemia
Diagnostic values for anemia
M: <13.0 g/dL
F: <12.0 g/dL
Diagnostic approach to anemia
S/s Lab tests History PE Peripheral blood smear Retics count
First and important step in diagnostic
History
History includes
Nutritional status Easy fatigability Family history Drug intake Presence of chronic disease Inflammatory diseases Menstruation and pregnancy history
At-risk population
Children
Adolescents
Pregnant
Elderly
S/s to check in PE
Pallor
Pale conjuctiva
Systolic flow murmur
Palmar creases lighter in color than the surrounding tissue
Oxygen-carrying capacity
Hemoglobin
Percentage of RBCs in relation to the entire volume of blood
Hematocrit
Indicative of cell size
Measured in femtoliters
Mean corpuscular volume
MCV diagnostic values for anemia
<80 fL - microcytosis
>100 fL - macrocytosis
Amount of Hb in a particular red cell
Measured in pg
Mean corpuscular hemoglobin/mea
Amount of Hb in a certain volume
Increased in hereditary spherocytosis
Mean corpuscular hemoglobin concentration
Measure of variance of the red cells in a particular blood sample
Increased in hemolysis, thalassemia, post-blood transfusion
RBC distribution width
Increases when bone marrow is trying to recover
Monocytes
PBS result for IDA
Microcytic, hyprochromic anemia
PBS result for megaloblastic anemia
Macrocytic, normochromic anemia
Possible causes of megaloblastic anemia
B12 and folate deficiencies
D. latum infection
What causes folate deficiency
Low vegetables intake
Malabsorption
Gastric bypass
Provides important information about defects in the red cell production
Used as a complement to the red cell indices indicated in the CBC
PBS
Variation in cell size
Anisocytosis
Small red cells with no central pallor
Correlates with increase in RDW
Spherocytes
Variation in cell shape
Suggests defect in maturation of red cell precursors
Poikilocytosis
Have bull’s-eye appearance and are seen in thalassemia and in liver disease
Membrane is pulled towards the center as it tries to preserve its volume
Target cells
Red cells that are recently released from the bone marrow
Seen in polychromasia
Reticulocytes
Abnormally high number of immature red blood cells in circulation
Polychromasia
Used to see if the marrow is responding to the anemia
Corrected reticulocyte count (Retic %)
Determine whether anemia is hypoproliferative
RPI (reticulocyte production index)
Normocytic, normochromic could be indivicative of hypoproliferative diseases which include
Marrow damage
Iron deficiency
Dec stimulation: inflammation, metabolic disease, renal disease
Microcytic or macrocytic could be indicative of maturation disorder which include
Cytoplasmic defects (iron def, thalassemia*, sideroblasmic anemia) Nuclear defects (Folate, B12 def, drug toxicity, refractory anemia)
RPI > 2.5 is indicative of
Hemolysis or hemorrhage
Marrow infiltration or fibrosis
Myelopthsis
Normocytic, normochromic red cells with inappropriately low reticulocyte response
Hypoproliferative anemias
Hypoproliferative anemias: microcytic, hypochromic
IDA
Thalassemia*
Myelodysplastic syndrome (sideroblastic anemia)
Hypoproliferative anemias: macrocytic anemia
Vitamin B12, folate deficiency
Drug toxicity
Myelodysplastic syndrome
Refractory anemia
Hypoproliferative anemias: normocytic, normochromic anemia
Myelopthsis anemia
Anemia of inflammation
Anemia of chronic renal disease
Aplastic anemia
Second most common cause of normocytic, normochromic anemia
Hyporesponsive to EPO
Anemia of inflammation
Cause of aplastic anemia
Bone marrow failure disorder
Proliferative anemia
Acute blood loss
Hemolysis
Common clinical features of hemolysis
Jaundice
Tea-colored urine
End-stage in a long process of iron loss
Iron deficiency anemia
Three stages in iron loss
Negative iron balance
Iron deficient erythropoiesis
Iron deficiency anemia
Body’s demand of iron exceeds the body’s ability to absorb iron from diet
Iron deficit must be made up mobilizing iron stores
Red cell morphology and indices are still normal
Negative iron balance
When iron stores fall to 15-20% of total, hemoglobin synthesis becomes impaired
Appearance of microcytic and hypochromic reticulocytes
Iron deficient erythropoiesis
When hemoglobin and hematocrit begin to fall
Iron stores are at around 10-15% of total
Iron deficiency anemia
Iron is absorbed in the ____, which requires an acidic environment
Duodenum
Two forms of iron
Heme iron
Nonheme iron
Comes from the hemoglobin and myoglobin in meat
Transported to the heme transporter inside the mucosal cell where eventually it will be bound with proferritin to become ferritin
Heme iron
Comes from soil, usually found in plants
Has a lower rate of absorption
Nonheme iron
Daily intake of iron from diet
10-20 mg
Causes of iron deficiency anemia
Increased physiologic demand for iron
Increased iron loss
Decreased iron intake or absorption
Fissuring of the angles of the mouth
Angular cheilitis
Spooning of the nails
Koilonychia
Unexplained craving for non-food item
Pica
Treatment and management of iron deficiency anemia
Blood transfusion
Oral tablets
250 mL of bag = ___ of iron
250 g
One tablet of ferrous sulfate contains ___
65 mg of elemental iron
Side effects of iron intake
Constipation
Hyperacidity
Secondary hemochromatosis
Iron salts are deposited into tissues leading to liver damage and bronze discoloration of skin
Secondary hemochromatosis
Iron should be give for ____ months in order to build enough stores of iron to prevent recurrence of anemia
6-12
Inherited disorder of hemoglobin synthesis
Thalassemia
Inability to synthesize alpha chains
a-thalassemia
a-chains are located in chromosome ___
16 (4 genes)
Inability to synthesize beta chains
b-thalassemia
b-chains are located in chromosome ____
11 (2 genes)
Deletion of all 4 alpha chains
Incompatible with life
Carries oxygen but does not distribute it to the tissues
Hydrops fetalis with hemoglobin Barts
Marrow expansion leading to bulging skull and maxilla
Chipmunk facies
Clinical features of thalassemia
Chipmunk facies
Splenomegaly
Sunburst appearance
Hydrops fetalis
Diagnosis of thalassemia
Hemoglobin electrophoresis
Able to sequester free flowing iron to prevent tissue damage
Iron chelators (deferaslrox)
To increase progenitor cells for treating patients with thalassemia
Bone marrow transplant
Decreased proliferation of all cell lines
Immune-mediated T-cell destruction of marrow precursor cells
Aplastic anemia
Most common cause of aplastic anemia
Idiopathic
Diagnosis of aplastic anemia
Done in the posterior superior iliac spine
Bone marrow aspirate
Treatment of aplastic anemia
Bone marrow transplant Supportive treatment (WBC infusion, immunosuppressant e.g. clyclosporine, antithymocyte globulin)
