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Flashcards in Anaemia Deck (22)

What is anaemia?

• Reduction in red cell mass
• Reduction in oxygen carrying capacity of the blood with resultant reduced oxygen delivery to tissues


What's the aetiology of anaemia?

– Decreased production
• EPO – Increased Destruction
• haemolysis – Bleeding


What are the signs and symptoms of anaemia?

• Neurological Dizziness, fainting, lack of concentration Blurred or diminished vision Headache, tinnitus Paraesthesia in the fingers and toes Insomnia, irritability.
• CVS: Angina, dysponea, palpitation and intermittent claudication by exertion HF in severe cases or presence of other organic cardiac disease, it is high COP failure.
• Musculo skeletal: Easy fatigability.
Tiredness and lassitude.
• GI – Anorexia, Dyspepsia
• GUM – Menorrhagia


How can you measure anaemia?

• Hemoglobin = grams of hemoglobin per 100 mL of whole blood (g/dL)
• Hematocrit = percent of a sample of whole blood occupied by intact red blood cells
• RBC = millions of red blood cells per microL of whole blood
• MCV = Mean corpuscular volume – If > 100 → Macrocytic anemia
– If 80 – 100 → Normocytic anemia – If < 80 → Microcytic anemia
• RDW = Red blood cell distribution width – =(Standarddeviationofredcellvolume÷meancellvolume)×100
– Normal value is 11-15% – If elevated, suggests large variability in sizes of RBCs


What are the Laboratory Definitions of Anemia?

• Hgb: • Women: < 13.5 • Hct (haematocrit):
• Women: < 36 • Men: <41


What are the symptoms of anemia?

Decreased oxygenation
– Exertional dyspnea
– Dyspnea at rest
– Fatigue
– Bounding pulses
– Lethargy, confusion
Decreased volume
– Fatigue
– Muscle cramps
– Postural dizziness
– syncope


What are Special Considerations in Determining Anemia?

Acute Bleed
• Drop in Hgb or Hct may not be shown until 36 to 48 hours after
acute bleed (even though patient may be hypotensive)

Pregnancy • In third trimester, RBC and plasma volume are expanded by 25
and 50%, respectively.
• Labs will show reductions in Hgb, Hct, and RBC count, often to anemic levels, but according to RBC mass, they are actually polycythemic

Volume Depletion
• Patient’s who are severely volume depleted may not show anemia until after rehydrated


What is the RBC Life Cycle?

• In the bone marrow, erythropoietin enhances the growth of differentiation of burst forming units-erythroid (BFU- E) and colony forming units-erythroid (CFU-E) into reticulocytes.
• Reticulocyte spends three days maturing in the marrow, and then one day maturing in the peripheral blood.
• A mature Red Blood Cell circulates in the peripheral blood for 100 to 120 days.
• Under steady state conditions, the rate of RBC production equals the rate of RBC loss.


What are the Causes of Anemia?

1. Erythrocyte Loss through
2. Low Erythropoietin levels
3. Decreased response to erythropoietin
4. Iron deficiency
5. Decreased marrow response (thalassemia)
6. Destruction of red blood cells


What are the causes for Decreased Response to Erythropoietin? (which causes anaemia)

• Iron-Deficiency
• VitaminB12 Deficiency
• Folate Deficiency
• Anemia of Chronic Disease


What are the causes of erythrocyte loss?

• Bleeding:
-Chronic (gastrointestinal, menstrual)
-Acute/Hemodynamically significant: – Gastrointestinal – Retroperitoneal


What are the causes of Low Erythropoietin levels?
(Erythropoeitin controls red blood cell production)

• Kidney Disease
– Normochromic, normocytic
– Low reticulocyte count
– Frequently, peripheral smear in uremic patients show “burr cells” or echinocytes
– Target hemoglobin for patients on dialysis is 11 to 12 g/dL
• Administer erythropoietin or darbopoietin weekly • Good Iron stores must be maintained
- Iron Deficiency
– Can result from: – Pregnancy/lactation
– Normal growth – Blood loss – Intravascularhemolysis – Gastric bypass – Malabsorption
» Iron is absorbed in proximal small bowel; decreased abosrption in celiac disease, inflammatory bowel disease
– May manifest as PICA • Tendency to eat ice, clay, starch, crunchy materials
– May have pallor, koilonychia of the nails, beeturia
– Peripheral smear shows microcytic, hypochromic red cells with marked anisopoikilocytosis.


What is koilonychia?

A sign of iron deficiency anaemia. Presents as cracked nails with white lines in them.


What are the lab findings that indicate iron deficiency anaemia?

• Serum Iron
• LOW (< 60 micrograms/dL) • Total Iron Binding Capacity (TIBC)
• HIGH ( > 360 micrograms/dL) • Serum Ferritin
• LOW (< 20 nanograms/mL) • Can be “falsely”normal in inflammatory states


What are the treatments for iron deficiency anaemia?

• Oral iron salts
– Ferrous sulfate – 325 mg po Q Day • Side effects: constipation, black stools, positive
hemmoccult test – Vitamin C can facilitate iron absorption.


What's the treatment of vit.B12 deficiency?

• Vitamin B12 – 1000 micrograms intramuscularly monthly -OR-
• Vitamin B12 – 1000-2000 micrograms po QDaily


What's the treatment of folate deficiency?

• Folate – 1 to 5 mg po Qday
• Vit. B12 deficiency must be excluded in folate-deficient patients, because supplemental folate can improve the anemia of Vit. B12 deficiency but not the neurologic sequelae.


What is anaemia of chronic disease?

• Usually normocytic, normochromic (but can become
hypochromic, microcytic over time)
• Occurs in people with inflammatory conditions such as collage vascular disease, malignancy or chronic infection.
• Iron replacement is not necessary • May benefit from erythropoietin supplementation.


What causes destruction of red blood cells?

• Hemoglobinopathies • Sickle Cell Anemia
• Aplastic Anemia • Decrease in all lines of cells – hemoglobin, hematocrit,
WBC, platelets • Parvovirus B19, EBV, CMV • Acquired aplastic anemia
• Hemolytic Anemia


What are the results of lab analysis of Hemolytic Anemia?

• Increased indirect bilirubin
• Increased LDH
• Increased reticulocyte count • Normal reticulocyte count is 0.5 to 1.5%
• > 3% is sign of increased reticulocyte production, suggestive of hemolysis
• Reduced or absent haptoglobin • < 25 mg /dL suggests hemolysis
• Haptoglobin binds to free hemoglobin released after hemolysis


What medical problems could cause anaemia?

-Sickle cell Disease
– Thalassemia
– Renal Disease
– Hereditary Spherocytosis


How should you evaluate a patient with anemia?

Any jaundice, elevated bilirubin, suspicious for hemolysis?
Any history of medical problems that could cause anemia? Are the other cell lines also low?
– If WBC and platelets are both low, consider APLASTIC ANEMIA! – Check medication list
» NSAIDS (phenylbutazone), Sulfonamides, Acyclovir, Gancyclovir, chloramphenicol, anti-epileptics (phenytoin, carbamazepine, valproic acid), nifedipine
» Check parvovirus B19 IgG, IgM » Consider hepatitis viruses, HIV
– If Platelets are low consider TTP or HUS! – Must check smear for schistocytes (for sign of microangiopathic
hemolytic anemia) – If renal failure, E. Coli O157:H7 exposure → HUS – If renal failure, neurologic changes, fever → TTP