Anemia Flashcards
Thrombophilia
hypercoagulopathy, Thrombophilia is a risk factor for pathologic formation of an intravascular blood clot (thrombosis)
risk factors for thrombosis
stasis and vascular wall abnormalities, Thrombosis is usually a multifactorial condition
virchows triad
endothelial damage, hypercoaguability, stasis
Reasons for endothelial damage
smoking, htn, surgery, PICC lines, trauma
Reasons for hypercoaguability
heredity: factor V, prothrombin, protein C deficiency. acquired: cancer, chemo, pregnancy, obesity
Reasons for stasis
immobility, polycythemia
Inherited (autosomal dominant) causes
Protein C, protein S deficiency (inhibits f. V, VIII)
Factor V Leiden* most common (mutation f. V > resistance to inactivation)
Acquired causes
Malignancy (20% of all VTE occur in patients with cancer)
Pregnancy up to 2 months postpartum
Oral contraceptives or estrogen replacement therapy
Clinical features of inherited thrombophilia
Thrombosis before age < 50 years
Recurrent venous thrombosis DVT and PE
Family history of thrombosis before age 50
Thrombosis is more often when other factors are present (pregnancy, oral contraceptives, immobility)
Testing for inherited thrombophilia
ROUTINE thrombophilia testing is NOT recommended ( doesn’t affect management)
Available testing:
Protein C activity essay (abnormal in protein C deficiency)
Protein S activity essay (abnormal in protein S deficiency)
Protein C resistance essay (abnormal in factor V mutation)
PT/INR (normal)
Platelets (normal)
Thrombophilia therapy
Treat DVT/PE with anticoagulation therapy (Warfarin, direct oral anticoagulants ) for a minimum of 3 months (optimal length of the treatment is unknown)
IVC filter if there is a contraindication to anticoagulation
Anemia
Anemia is a deficits in the mass of circulating RBC ( the capacity to deliver oxygen is compromised) Measured as RBC count, concentration of Hgb (g/dl), % of Hct
What is hemoglobin
is a protein contained in RBC that is responsible for delivery of oxygen to the tissues Hct is a % of the volume of RBC in the total volume of a blood sample
Hgb: Hct
1:3
Normal Hgb
13.5-17.5 g/dl (male), 12-16 g/dl (female)
Hgb suggestive of anemia
Hgb concentration <14 g/dl in men and <12 g/dl in women suggests anemia
Symptoms of anemia
oxygen-caring capacity: tiredness, exercise intolerance, poor concentration, pallor, angina
cardiac compensation ( stroke volume, HR): palpitations, dyspnea on exertion, systolic murmur (hemic murmur)
Sx are minimal when
it is gradual and mild
MCV range
80-100
Microcytic
< 80
Macrocytic
> 100
Normocytic
80-100
Microcytic anemias (low MCV)
Small RBC (microcytosis) 90% of RBC volume composed of hgb. Hgb is a major contributor to the cell size Due to decreased production of Hgb
Hemoglobin made of
Made of Heme and Globin
Heme is mainly composed of iron ( that binds O2)
Reduction in any of these components will result in microcytic anemia
Microcytic anemia etiology
Iron deficiency anemia (IDA)
Anemia of chronic disease (ACD)
Thalassemia
IDA
Most common reason for anemia worldwide
Deficiency is due to
dietary lack : meat (better absorption), sunflower seeds, nuts, whole grains, dark leafy greens
poor iron absorption in duodenum (rare, Celiac disease)
increased iron demands (pregnancy)
blood loss (most common cause in adults, GI)
Manifestation of IDA – iron deficiency
Pica (ice, clay)
Restless leg syndrome
Manifestation of IDA – Low hemoglobin
Tiredness Generalized weakness Shortness of breath Pallor Hemic murmur
Diagnosis of IDA: CBC is an initial test – results on the CBC:
Low Hgb/Hct
Low MCV < 80 fL
Low MCHC (mean corpuscular hemoglobin concentration= the amount of Hgb per unit volume) < 33 g/dl
Increased RDW (red cells distribution width) > 15%
Low reticulocyte count
IDA blood smear
Low MCV on CBC MICROCYTOSIS on the blood smear
Low MCHC on CBC HYPOCHROMIA on blood smear
IDA blood smear red blood cells
Increased RDW on CBC ANYSOCYTOSIS on blood smear
Diagnosis of IDA : iron study (diagnostic)
Low serum iron (N 50-150 ng/dl)
Low ferritin (N 20-300 ng/dl)
Low % transferrin saturation (N 20-50%)
High TIBC (Total Iron Binding Capacity) (N 25-450 ng/dl)
Low reticulocyte (“young cells” just released from bone marrow) count
Stages of IDA – stage 1
(1) : Iron storage is depleted without causing anemia (ferritin) – asymptomatic
stage 2
(2) : Normocytic anemia (Hgb, normal MCV and normal reticulocyte count) – asymptomatic or mild symptoms of anemia
stage 3
(3) : Microcytic hypochromic anemia (low MCV, low MCHC, low reticulocyte count)- symptomatic