Small paeds topics Flashcards
What are the two most common severe inherited coagulation disorders?
Haemophilia A
Haemophilia B
What type of inhertiance are haemophilias?
X linked recessive
Which is more common haemophilia A or B?
A - 5x more common
What is the cause of haemophilia a?
Defective synthesis of VIII
What is the main symptom of haemophilia?
BLEEDING
What is bleeding into muscles called?
Haemarthroses
What clotting time will be longer in haeophilia a/b?
APTT
What is the management for haemophilia a/b?
Give the factor they are short of
A=8
B=9
What is the complication of giving clotting factors as treatment?
Antibodies to factors
Which drug can be used to treat mild haemophilia A?
Desmopressin
What is the cause haemophilia b?
Deficiency of clotting factor 9
What is VWF disease?
VWF factor (released by activated thrombin) preents degradation of factor 8 complex from degradation. Decreased VWF = decreased clotting ability
What is the standard treatment of children with IDA?
5mg/kg/day of ferrous suplhate + vitamin C (improves absortption)
What type of anaemia do you get in IDA?
Microcytic anaemia
Hypochromic
low MCV
low MCH
What happens to reticulocytes in IDA?
Decreased (rise in a few days of treatment)
What investigation would show you sickle cell disease?
Blood film
What investigation would show G6PD deficiency and pyruvate kinase deficiency?
Red cell enzyme studies
When do most children become symptomatic in IDA?
Hb drops below 70g/L
What investigation would you nee to do to diagnose a thallasaemia?
Haemoglobin electrophoresis
Explain how Iron deficiency leads to anaemia?
Decreased production of red blood cells due to ineffective erythropoiesis
Main 3 causes for IDA?
Inadequate intake
Malabsorption
Blood loss
What type of anaemia does thalassaemia cause?
Microcytic
What type of anaemia does thalassaemia cause?
Microcytic
What are the different severity of B thalassamia?
All affected individuals a have a severe reduction in B globin
B major - HbA (a2b2) cannot be made because abnormal B globin gene
B intermdia - B globin mutation allows a small amount of HbA and/or HbF to be produced
What happens as the result B thalassaemia?
1) Severe anaemia within 3/12 (transfusion dependent)
2) Extra medullary haemopoeisis (prevented by regular blood transfusions) –> patinets develop hepatosplenomegaly and bone marrow explansion
3) bone marrow expansion can lead to maxillary overgrowth and skull bossing
What chrmosome is affected for thalassaemia B?
11
What is the treatment for B thalassaemia?
Transfusions life long (Bone marrow transplant - cure, need a HLA identical sibling)
What are the complications with transfusions for B thaassameia?
1) IRON DEPOSITION
2) antibody formation - 10% - aallo-antibodies to transfused red cells in the patient make finding compatible blood difficult
3) venous access
What is a ‘cure treatment’ for B thalassaemia?
Bone marrow transplantation
Can you test prenatally for B thalassaemia?
Yes in CVS - for at risk people
Who is sickle cell disease more common in?
African and carribean
What is sickle cell disease?
You get HbS instead of HbA. This makes the RBC sickle shaped
What is sickle cell trait?
one HbS from one patent and one normal B globin gene
What are the features of sickle cells?
Low life span
Can be trapped in the microcirculation resulting in blood vessel occlusion and thus iscahemia in an organ or bone (the trapping is exacerbated by low oxygen tension, dehydration and cold)
How do homozygotes present?
Recurrent episodes of haemolysis crises (from infancy)
What organisms do sickle cell sufferers have an increased susceptibility to?
Encapsulated organisms - pneumococci and haemophilus influenzae
Also increased of incidence of osteomyelitis caused by salmonella and otehr organisms
