Anemia Flashcards
Anaemia causes?
- Defective RBC production (nutritional) OR ↑ RBC destruction (hemolysis)
- Blood loss (parasites, ulcers, tumors, ↑ menstruation)
- BM replacement, abnormal Hb/RBC, chronic systemic diseases
Anaemia signs & symtoms?
- Palor (skin, mucous membranes, conjunctivae)
- Exertional dyspnoea, fatigue, tachycardia
- Eyes red in sever anemia
- CNS: fainting
- Heart: Chest pain, angina & heart attack
Classification of and their subtypes?
- Microcytic <80 dL:
-Iron deficiency anaemia
Anaemia of chronic
disease
-Thalassaemia
-Sideroblastic anaemia - Normocytic anemia 80-90 dL
-Hemolytic anaemia
-Aplastic anaemia (bone
marrow disorders) - Macrocytic >90 dL:
-Megaloblastic anaemia
(Vit. B12, folate
deficiency, drug induced)
-Non-megaloblastic
anaemia (alcohol abuse,
hypothyroidism,
pregnancy)
Iron Deficiency Anaemia?
Iron deficiency the most common cause → hypochromic microcytic RBCs
Iron Deficiency Anaemia Pathogenesis?
blood loss (menstruation, GIT, trauma); increased
requirements (pregnancy); decreased absorption (e.g. regional enteritis)
-Most common in children and women of child bearing age
-In pregnancy and nursing females: folate deficiency and/or combined iron/folate
deficiency commo
Symptoms of iron deficiency
-pallor
-lethargy
-fatigue
Iron Deficiency Anaemia treatment goals?
Normalise Hb and hematocrit (Htc) and replenish body iron stores
Iron Deficiency Anaemia Non-pharmacological treatment:
- Identify the cause; e.g. chronic blood loss, and remove it if possible
- Patient counselling, lifestyle modifications/adjustments
Iron Deficiency Anaemia drug tx?
Adm of Iron preparations (necessary for Hb production):
- Oral (ferrous salts): ferrous sulphate, ferrous gluconate, ferrous fumarate, ferrous bisglycate (amino acid chelate)
- Parenteral : Iron dextran, Iron sucrose
Factors affecting iron absorption that Increasing iron absorption?
- Vitamin C (ascorbic acid)
- Citric acid
- Gastric secretions
- Hydrochloric acid
- Acidic pH
Factors affecting iron absorption that Decreasing iron absorption?
1. Phytate
2. Phosphate
3. Tannate
4. Tetracycline
5. EDTA
6. Milk
7. Alkaline pH
Oral Iron Preparations
- Indications(2)
- CI(4)
- Cautions(2)
- DI(7)
- A/E(4(
- Indications:
Prophylaxis and Tx of iron deficiency anaemia - CI:
iron overload, chronic alcoholism, liver disease, repeated blood
transfusion - Cautions:
-Geriatrics: may cause constipation, faecal impaction, reduced
absorption may necessitate large doses
- Paediatrics: accidental poisoning common (use correct doses) - DI:
Compounds containing Ca, Mg, Al, Bicarbonates, Phosphates
(decreased absorption); Tetracyclines (↓absorption of both), Vitamin E
impaired response to iron therapy - A/E:
nausea
epigastric pain
diarrhoea
constipation
Parenteral Iron Preparations Include?
- Iron polymaltose (IM)
- Iron Sucrose (IV)
- Iron dextran ( IM/slow IV) iron
- carboxymaltose (IV)
- iron isomaltoside (IV)
Why would oral iron therapy fail & what is the solution?
- Due to non-adherence, inflammation, malabsorption, continuing blood loss
SOLUTION:
(Malabsorption can be evaluated by measuring iron levels every 30 mins
for 2 hrs after admin of 50mg of ferrous sulphate)
2.If plasma iron levels increase by >50%, absorption is adequate
- Intolerance to oral therapy
- Required antacids therapy
- Significant blood loss in pts refusing transfusion
Parenteral Iron Preparations?
- Iron carboxymaltose
(I.V
Iron isomaltoside (I.V) - Iron dextran OR Iron
sucrose (I.M/ I.V) - Iron isomaltoside (I.V)
- Iron polymaltose (I.V)
Iron carboxymaltose
(I.V
- Indications
- A/E(4)
- CI(2)
- Indications:
iron deficiency - A/E:
headache, N, rash,
phlebitis on injection
site - CI:
severe liver damage,
iron overload, 1st trim.
of pregnancy
Iron dextran OR Iron
sucrose (I.M/ I.V)
- Indications
- A/E(4)
- CI(5)
- Indications
severe iron deficiency
in adults - A/E(4);
metallic taste,
headache,
hypotension, N&V - CI(2)
Iron overload,
concurrent blood
transfusion, liver
disease, infection,
history of allergies
Iron isomaltoside (I.V)
- Indications
- A/E(5)
- CI(5)
- Indications:
iron deficiency - A/E(4)
N, rash, abdominal
disorders,
constipation, fever,
dyspnoea - CI(5)
severe liver damage,
iron overload,
infection, acute renal
failure, active RA, 1st
trim. of pregnancy
Iron polymaltose (I.V)
- Indications
- A/E(4)
- CI(3)
- Indications;
iron deficiency - A/E(4)
allergic reactions,
fever, leukocytosis,
tachycardia - CI(3)
haemolytic anaemia,
severe liver damage,
bone marrow
depression
Parenteral Iron Preparations general S/E?(3)
1.Anaphylactic reactions
2.Urticaria
3.Lymphadenopathy
Parenteral Iron Preparations allergies?
Parenteral iron preparations must be used with caution in
patients with history of asthma or allergies
Anaemia of Chronic Disease characteristics ?
↓↓↓ RBC count
Anaemia of Chronic Disease states?
- Infections
- Malignancy
- Diabetes
- Autoimmune disorders
Anaemia of Chronic Disease Cause?
Continuous inflammation by Chronic Disease
-Impairs iron metabolism → ↓RBC production
Anaemia of Chronic Disease Tx(3)?
- Resolve the underlying cause
- Blood transfusions for symptomatic anaemia
- Recombinant human erythropoietin (EPO); though expensive
Erythropoietin (EPO)?
Glycosylated protein hormone, haematopoietic growth factor
Erythropoietin (EPO) MOA?
stimulate erythropoiesis → increase RBC production
Recombinant erythropoietins?
- Epoetin alfa & beta
- darbepoetin alfa
Erythropoietin (EPO) A/E?
1.Hypertension
2. Headache
3. Seizures
4. Flu-like symptoms
5.Rash
6. pruritus
7. injection site reaction
Erythropoietin (EPO) CI(3)?
Uncontrolled
hypertension
myeloid
malignancy
known
hypersensitivity,
children <6 years,
untreated iron
deficiency
Thalassaemia
Erythropoietin (EPO) costs?
Expensive
Sideroblastic Anaemia plasma concentrations ?
↑ serum iron, ↓TIBC, ↑ ferritin level
Consequences of Immature RBC in bone marrow
- Can’t utilize iron for haem synthesis → iron accumulation in
mitochondria - Unused iron builds up in blood → ↓TIBC
Sideroblastic Anaemia Dx(2)?
- Bone marrow biopsy
- genetic testing
Sideroblastic Anaemia Tx?
Alcohol/meds cessation if that’s the cause;
vitamin/mineral supplementation;
bone marrow transplant.
Megaloblastic Anaemia
Caused by a deficiency of folic acid and/or vitamin B → large, oval
(macrocytic), well haemoglobinised RBCs.
Folic Acid Deficiency Anaemia?
Folic acid deficiency → insufficient DNA synthesi
Folic Acid Deficiency Anaemia causes?
Insufficient intake in diet, alcoholism, pregnancy
Folic Acid Deficiency Anaemia frequency?
Common in pregnancy and in the elderly
Why must folate deficiency be differentiated from B deficiency?
Folate deficiency must be differentiated from B deficiency because folate
can reverse the haematological but not the neurological damage caused by B deficiency
Types of megaloblastic Anaemia?
- Folic Acid Deficiency Anaemia
- Vitamin B Deficiency/ Pernicious
Anaemia
Vitamin B12 importance?
Vitamin B is essential for haematopoiesis,
maintenance of myelin and production of
epithelial cells
Vitamin B Deficiency/ Pernicious
Anaemia causes?
Impaired absorption (lack of intrinsic factor bacterial overgrowth)
Reason for admin for vitamin B12?
Oral absorption of Vit B is very poor, therefore it should be given parenterally
Vit B12 target?
Vit B deficiency occurs specifically in adults
Non-Pharmacological Treatment of Megaloblastic Anaemia?
Dietary modifications to ensure adequate intake of folate and vit B
Megaloblastic Anaemia tx goals?
- Normalise Hb
- Identify and treat the underlying cause (e.g. malabsorption)
Drug Treatment of megaloblastic anemia?
1.Folic acid; 5mg daily until normal Hb/ ↑demand stops (in pregnancy
give with Iron)
- Vitamin B 12 (Cyanocobalamin); IM, 1000μg, alternate days for 1
week, then monthly for life.
Aplastic Anaemia?
Anaemia caused by destruction or inhibition of red bone marrow
Drugs (e.g. chloramphenicol), cancer chemotherapeutics, and
insecticides (e.g. DDT)
