HAEMATOLOGY Flashcards
What are the components of Hb?
Fe
Globin chains - Beta, Alpha
Define anemia according to age
Neonates - <14g/dL
1 to 12M - <10g/dL
1 to 12yrs - < 11g/dL
Causes of Anemia
- Reduced RBC production
BM Failure-Leukemia, Infections
Malnutrition - Fe def, Folic acid Def, B12 def - Increased destruction
Enzyme - G6PD Def
Membrane - Hereditary spherocytosis, Hereditary Elipsocytosis
Hb - Thallesemia, Sickle Cell Anemia
Antiboides - Autoimmune, ABO - Blood Loss
Parasites - Hookworm
GIT - Meckel Diverticulum
GUT - Menstrual bleeding
Raw materials of Hb Production
Fe
Vit B12
Folic Acid
What is the most common cause of Anemia in SL? Why?
Fe Def Anemia
Poverty - Less consumption of Fe containing food
Parasites
Tea Consumption - Tannin inhibits Fe absorption
Poor Knowledge about Fe containing food
Causes of Iron Deficiency Anemia (IDA)
Poor Intake
Malabsorption
Blood loss
Hook Worm
C/F of IDA
Pallor
Glossitis
Koilonychia - Spoon shaped nails
In Severe anemia - Breathlessness, HF features
Food to avoid in excess in toddlers to prevent IDA
Cow’s milk
Tea - Tannin inhibits Fe absorption
High fibre food - Phytates inhibit Fe aborption
Ix for IDA
FBC - Low Hb
Blood Picture - Microcytic, hypochromic (MCV, MCH) cells. Aniscocytosis (Different shapes), Poikilocytosis (Different Sizes), Red cell Distribution Width (RDW) is high
S. Feritin is low
Causes of microcytic anemia
IDA
Thalassemia
Anemia of Chronic Disease
Sideroblastic anemia
What vitamin increases Fe absorption?
Vit C
What are the differences between IDA and Thalassemia Minor?
IDA - RDW is high, S. Feritin is low
Thalassemia Minor - RDW normal, S. Ferritin is high
IDA Mx
Mx depends on the severity and the cause
If anemia is severe, with breathlessness and HF features - Blood transfusion
Otherwise blood isn’t required
If underlying cause is malnutrition - Dietary advice: Eat fish, meat, green leafy vegetables
Rx worm infections
All IDA patients must be supplemented with Fe - Ferrous sulphate - 6mg/kg/day.
Should continued until after 3 months Hb returns to normal levels.
IV Fe if patient has malabsorption
Efficacy of Oral and IV Fe is the same. T/F?
T
What is Thalasemia?
A genetic disorder where abnormal alpha and beta globin chain production occurs.
Percentages of children of parents with thalassemia genes
25% - Healthy
50% - Carriers
25% - Diseased: Thalassemia Major
Pathophysiology of Beta Thalassemia
Autosomal recessive. If both parents have the gene, the child will inherit.
Beta globulin chain production is abnormal/less.
Alpha chains will bind with Gamma to form HbF.
Alpha chains will bind with Delta to form HbA2.
Red blood cells containing abnormal Hb will be destroyed in the spleen causing anemia.
What is done to identify the different types of Hb?
Hb electrophoresis
High performance liquid chromatography (HPLC)
C/F of a child with Thalassemia
Pale
Jaundice - Due to increased bilirubin (hemolysis)
Thalassemic facies - Frontal bossing, prominent maxilla, protruding teeth.
Hepatosplenomegaly
Short stature
Poor academic performance
What is the reason for Thalassemic facies and hepatosplenomegaly?
Its due to the increased production of Hb to compensate anemia
Rx of Thalassemia
Blood Transfusion
Side effect of the Rx of thalassemia
Fe overload
Complications of Fe overload in Thalassemia in Rx
Affects various organs - Fe induced organ damage
Brain - Pitutary: Decreased GH, FSH, LH
Pancreas - Diabetes
Thyroid - Hypothyroidism
Parathyroid - Decreased Ca, tingling sensation
Skin - Pigmentation
Liver - Hepatomegaly, Cirrhosis
Heart - Cardiomyopathy
Antibodies
Infections (Not common anymore) - Hepatitis, HIV, Malaria
Fe overload Mx
Fe chelation
Desferioxamine - Subcutaneous: atleast 8hrs/day, 6days/week
Deferisirox tablet - Dissolved in water
Cure for Thalassemia
Bone Marrow
Preferably from siblings
Upon inspection of a Thalassemic child, what is important to notice?
Insulin injection sites
Skin color in comparison to parents
Tingling sensation due to low Ca
Ix for Thalassemia
FBC - low Hb
Blood picture - Microcytic, hypochromic cells. Anisocytosis, Poikilocytosis
HbLC - HbA decreased, HbF Increased, HbA2 increased
S. Ferritin increased
Sugar levels
Ca Levels
Thyroxine levels
Abdominal scans - Hepatosplenomegaly
2D Echo
How do you calculate the amount of blood to be transfused in a Thalassemic patient?
(Expected Hb - Current Hb) * 4 * Body weight.
Amount of blood transfused per day - 10ml/kg
Construct a Mx plan for a Thalassemic Patient
Blood transfusion
Fe chelation to prevent Fe overload
Screening of Siblings using HPLC
Advice - Dietary advice, Explanation of diseases, Clinical visits
Cure - Bone marrow (usually sibling, Available in SL, 4-5mil cost)
Social support
Economical support - 500/month from SL Government
BM failure aka?
Aplastic anemia
Causes of aplastic anemia
Inherited
Acquired - Viral infections (Hep, Parvovirus) Drugs (sulphanomide, chemotherapy) Toxins (Benzene)
Idiopathic
C/F of aplastic anemia
Decreased rbc leading to anemia
Decreased WBC leading to infections
Decreased Platelets leading to bleeding and bruising
Rx of Aplastic anemia
Depends on the cause,
Blood transfusion if child is with sever anemia.
WBC transfusion if WBC low (Buffy coat of blood)
Platelet transfusion if low
If underlying cause can be identified, treat
If due to drugs, stop drugs
Main causes of Bleeding disorders
- Depleted clotting factors - Hemophilia.
Joint and muscle bleeding, Increased clotting time. - Platelet deficiency - Immune thrombocytic purpura.
Mucosal bleeding - gums, nose
Increased bleeding time
What are the commonest severe inherited coagulation disorders?
Hemophilia A and B
Inheritance patterns of Hemophilia
X linked recessive - Hemophilia A and B
1/3rd sporadic - Parents normal. Due to new mutations
C/F of Hemophilia
Bleeding into joints and muscles, may lead to arthiritis if not Rx.
40% in neonates, particularly with intracranial hemorrhage, post-circumscion, from heel stick and venopuncture sites.
Describe different levels of severity of Hemophilia A
Severe - <1% - Spontaneous Joint and muscle bleeding
Moderate - 1 - 5% - Bleeding upon mild trauma
Mild - >5 - 40% - Bleeding after surgery
Mx of Hemophilia
Recombinant factor 8 for Hemophilia A
Recombinant factor 9 for Hemophilia B
Major surgery and life threatening bleeding requires levels to be raised to 100%
Intramuscular injections, Aspirin, Ibuprofen, NSAIDS must be avoided.
DDAVP/ Desmopressin may help mild Hemophilia A without blood products.
Desmopressin is ineffective in Hemophilia B.
Hemophilia Ix
Clotting time increased
Bleeding time normal
aPTT increased
Factor 8 decreased - Hemophilia A
Factor 9 decreased - Hemophilia B
PT/INR Normal
Diseases in which PT/INR increases
Liver failure
Vit K def
DIC
Problem of vWD
Combination of platelet and clotting problems
vWF facilitates platelet adhesion - Deficiency leads to defective platelet plug formation
Its the carrier protein of factor 8
Cause of vWD
Quantitative or qualitative deficiency of factor 8
C/F of vWD
Bleeding from mucosa - gum, epistaxis
Bleeding from joints and muscles
Ix of vWD
Bleeding time, clotting time and aPTT increased
Mx of vWD
Desmopressin - Mild
Factor 8 Concentrate - Severe disease
Inheritance pattern of vWD
AD
Commonest subtype of vWD
Type 1
Fairly mild
Not diagnosed until puberty
What is the commonest cause of thrombocytopenia in children?
Immune thrombocytopenia
Cause of ITP
Immune mediated destruction of platelets. Megakaryocytes in BM
Onset after 1 to 2 weeks of a viral infection
C/F of ITP
Petechiae and purpura (Bleeding under the skin)
Superficial bleeding
Epistaxis, mucosal bleeding
Platelet counts falls to <10 * 10^9/L
D/d for thrombocytopenia
Dengi
ITP
Autoimmune
Malignancies
BM Failure
Complication of ITP
Intracranial hemorrhage
ITP Dx
Dx of exclusion
If hepatosplenomegaly, marked lymphadenopathy present, BM biopsy to exclude acute leukemia or aplastic anemia.
A bone marrow examination must be done is the child is treated with steroids
SLE must be excluded
ITP Mx
Supportive/symptomatic Mx
Steroids
Immunoglobulin
Splenectomy
If platelet count, >20,000 - Symptomatic Mx, advice
<20,000 + no bleeding - Prednisone
<20,000 + high risk of bleeding ( past hx of bleeding) or child doesn’t heed advice - IV Ig
Is there a place for platelet transfusion in ITP? Why?
No.
How much platelets given, it will be destroyed by antibodies.
