Paeds Haem Flashcards
Anaemia is Hb below normal. Anaemia in neonate = Hb below what?
<140 g/L in neonate
anaemia in <1yr = Hb below what?
<100g/L
anaemia in 1-12 yr olds = Hb below what?
<110g/L
Give me three overarching reasons why anaemia might happen.
- not enough red cells being made
- too many red cells being destroyed
- blood loss
What happens to HbF during first yr of life?
HbF high at birth then gradually replaced by HbA during first yr of life
One reason for anaemia is not enough red cells being made. Give me two reasons for not enough red cells being made.
ineffective erythropoiesis
red cell aplasia (i.e. none produced!)
One reason for anaemia is too many red cells being destroyed, a.k.a HAEMOLYTIC anaemia. Give me 4 reasons for too many red cells cells being destroyed.
membranopathies
enzymopathies
haemoglobinopathies
immune
too many red cells being destroyed, a.k.a.
haemolytic
Membranopathies, enzymopathies, haemoglobinopathies and immune are all examples of what reason for anaemia?
too many red cells being destroyed a.k.a HAEMOLYTIC
Give me an example of a membranopathy causing haemolytic anaemia.
hereditary spherocytosis
Give me an example of an enzymopathy causing haemolytic anaemia.
G6PD deficiency
What is haematocrit?
proportion of the blood that’s cellular (usually 45% cells and the rest plasma)
Give me 2 examples of haemoglobinopathies causing haemolytic anaemia.
sickle cell + thalassaemia
Three causes of normocytic anaemia
anaemia of chronic disease
pregnancy
mixed haematinic (eg iron + folate)
2 causes of macrocytic anaemia
b12/folate deficiency
alcohol
In which type of anaemia would there be a high reticulocyte count?
haemolytic
lots of new red cells having to be produced bc they’re being destroyed all the time
In which type of anaemia would there be a high reticulocyte count?
haemolytic
lots of new red cells having to be produced bc they’re being destroyed all the time
Give me an example of immune cause of haemolytic anaemia.
haemolytic disease of the newborn
Tell me something about ‘aplastic anaemia’.
it’s bone marrow failure and part of PANCYTOPENIA (low rbcs, wbcs, and plts)
One reason for anaemia is blood loss. Give me three examples of kids blood loss causing anaemia.
fetomaternal bleeding
GI e.g. meckels diverticulum
bleeding disorder e.g. von willebrands
One reason for anaemia is not enough red cells being made. This can happen due to ineffective erythropoiesis or red cell aplasia. Give me three examples of things that would cause ineffective erythropoiesis.
iron def
folate def
chronic infl
One reason for anaemia is not enough red cells being made. This can happen due to ineffective erythropoiesis or red cells aplasia. Give me two examples of things that would cause red cell aplasia (a.k.a rbcs not prod).
Diamond Blackfan
Parvovirus B19
Diamond Blackfan
Parvovirus B19
both causes of…
red cells apalsia –> not enough red cells being made
iron def
folate def
chronic infl
all causes of…
ineffective erthyropoiesis –> not enough red cells being made
Give me some symptoms of iron def anaemia in kids.
fatigue
pallor
Pica!
SOB if severe
What might cause iron def anaemia in kids? (x4)
malnutrition e.g. EBF beyond 6 months
malabsorption e.g. hookworm
rapid growth / puberty
blood loss e.g. meckels
exclusive breastfeeding beyond 6 months is a risk for..
iron def anaemia
What kind of anaemia do coeliac and hookworm cause?
iron def (malabsorption)
A child presents with slow feeding and tires easily. Mum has noticed he has started putting soil in his mouth. What might you see on examination of cojunctivae / tongue / palmar creases?
PALLOR
What would FBC show in iron def anaemia, in terms of:
a) Hb
b) MCV
c) MCHC
iron def anaemia: low Hb low MCV (microcytic) low MCHC (hypochromic)
what is MCHC on FBC?
mean corpuscular haemoglobin concentration
e.g. low MCHC =hypochromic
What is MCV on FBC?
mean corpuscular volume
e.g. low MCV = microcytic
13 yr old girl who has just gone into puberty and had a growth spurt presents with tiredness, pallor and SOB. You suspect iron def anaemia. What investigations do you do?
FBC
blood film
serum ferritin
A coryzal 6yr old with coeliac presents with tiredness and pallor. You check serum ferritin and it’s raised. You are confused - you expected it to be low since you’re pretty sure he has iron def anaemia due to malabsorption. Why could this result be?
serum ferritin is an acute phase reactant so can get raised in illness (clue = coryza)
therefore check CRP too
A child’s FBC and blood film shows microcytic hypochromic anaemia - you suspect iron def. What would you expect from her serum ferritin and total iron binding capacity?
low serum ferritin
increased total iron binding capacity
(lots of spare carriers not being filled)
What drug is used to treat iron def anaemia? (inc dose + freq)
- ORAL FERROUS SULPHATE / fumurate 5mg/kg daily
What is the treatment for iron def anaemia? I want all the details.
oral ferrous sulphate / fumurate 5mg/kg daily
until Hb normal then continue for 3 months after
+ dietary advice!
How long do you continue the ferrous sulphate after the Hb has normalised?
3 months
don’t forget dietary advice
Give me three drugs that can cause folate def.
trimethoprim
nitrofurantoin
valproate
What is the treatment for folic acid def?
5mcg/kg folic acid
+ dietary advice
**NEVER TREAT W FOLIC ACID ALONE UNLESS B12 KNOWN NORMAL
(risk of cord degen)
What is important to remember about treating folate def anaemia?
never treat w folic acid alone unless b12 known normal
risk of cord degen
Give me three causes of b12 def.
malnutrition (vegans)
malabsorption
PERNIIIIICIOUS ANAEMIA (autoimmune, no intrinsic factor - can’t absorb)
What is the treatment for b12 def?
IM hydroxocobalamin injections
like pete has
what is that word for b12 injections
hydroxocobalamin
You do FBC and blood film for folate def anaemia. What do you expect to see?
macrocytic anaemia
What investigations for susepcted b12/folate anaemia?
FBC
blood film
serum folate / B12
Child presents with pallor, fatigue, GLOSSITIS and HYPOTONIA. Potentially some developmental delay. FBC and blood film show a macrocytic anaemia. What’s your diagnosis and what other test would show it?
b12/folate deficiency
serum b12/folate
Symptoms of b12 and folate def?
pallor, fatigue, GLOSSITIS, HYPOTONIA, dev delay
might end up with ataxia and bad vibration sense!!
what would expect from reticulocyte count in red cell aplasia (diamond blackfan, parvovirus b19)
low reticulocytes
If hereditary spherocytosis is very troublesome, what might you need to do?
splenectomy
(they’ll need lots of vaccines)
before that - try oral folic acid, blood trasnfusions and cholecystectomy if gallstones
Why does herediatry spherocytosis lead to too many red cells being destroyed?
they’re a funny shape so less deformable so get destroyed in spleen
Jaundice, gallstones, anaemia and splenomegaly. Blood film show lots of reticulocytes and spherocytes. what’s this?
hereditary spherocytosis.
Where is G6PD deficiency most prevalent?
Africa, middle + far East
what inheritance is G6PD def?
X linked recessive
Neonatal jaundice, and intermittent acute haemolytic reactions precipitated by febrile infection, fava beans, and mothballs.
G6PD deficiency
What would you see on blood film in G6PD def?
high reticulocytes
Heinz bodies! (think beans)
What is the most severe form of sickle cell?
HbSS
(least severe is ‘sickle cell trait - asymp, HbS from one parent).
Point substitution on the B globin gene (glutamine to valine). What’s this?
sickle cell
When does sickle cell usually present?
3 months - 6yrs
Tell me about the pathophysiology of sickle cell.
HbS polymerises within rbcs making them sickle shaped and increasing blood viscosity
have shorter lifespan + get destroyed early
vaso occlusion of small vessels - ischaemia + infarction.
Why does sickle cells usually present after 3 months?
run out of HbF
I want 7 consequences of sickle cell.
anaemia infection priapism vaso-occlusive crisis aplastic crisis sequestration crisis long term probs e.g. stroke
Give me an example of sickle cell infection
salmonella osteomyelitis
Cold, dehydration, infection and hypoxia are all precipitants of what in sickle cell?
vaso-occlusive crisis
What can happen to long bones as a result of sickle cell vaso occlusive crisis?
avascular necrosis
What can happen to chest as a result of sickle cell vaso-occlusive crisis?
“acute chest syndrome” - severe hypoxia
What triggers aplastic crisis in sickle cell?
parvovirus B19
Boy with sickle cell has sudden abdo pain + circulatory collapse. What is happening?
sequestration crisis
rbcs trapped in spleen / liver
What happens in a sequestration crisis?
rbcs trapped in spleen / liver
– sudden abdo pain + circulatory collapse
Give me some examples of long term problems in sickle cell.
stroke
heart failure
delayed puberty
All newborns are screened for sickle cell. When are all Afro-Caribbean kids also screened?
before general anaesthetic.
Why does sickle cell cause anaemia?
haemoglobinopathy – too many red cells being destroyed (haemolytic)
What is the general treatment for ALL acute crises in sickle cell?
analgesia
fluids
oxygen
Abx if fever
All sickle cell crises need analgesia, fluids, oxygen and Abx if fever. In aplastic crisis or sequestration crisis, they need:
blood transfusion
All sickle cell crises need analgesia, fluids, oxygen, and Abx if fever. In acute chest syndrome or priapism, they need:
exchange transfusion!
What does maintenance treatment involve for children with sickle cell?
PROPHYLAXIS
daily oral folic acid (to help make more rbcs)
bad - HYDROXYCARBAMIDE
:/ bone marrow transplant
What 3 things does PROPHYLAXIS for sickle cell kids involve?
lifetime oral Pen V
vaccinations
avoid triggers
If they survive it, this treatment is curative for sickle cell:
bone marrow transplant
Where is thalassaemia most prevalent?
Indian subcontinent + Middle East
In what population is sickle cell most prevalent?
Afro-caribbean
Which form of thalassaemia causes hydrops + death in utero?
alpha thalassaemia major.
east asians
Which two forms of thalassaemia are asymptomatic?
beta and alpha thalassaemia TRAITS
Which form of sickle cell is asymptomatic?
sickle cell trait
Which form of thalassaemia causes severe anaemia, faltering growth and hepatosplenomegaly in childhood?
Beta thalassaemia major
What are the symptoms of beta thalasseamia major?
severe anaemia
faltering growth
hepatosplenomegaly
Why does thalassaemia cause anaemia?
haemoglobinopathy – too many red cells being destroyed (haemolytic)
Beta thalassaemia major is fatal without treatment. What’s treatment?
lifelong monthly BLOOD TRANSFUSIONS
with iron chelation to avoid haemochromatosis
What treatment is curative for beta thalassaemia major?
bone marrow transplant
The treatment of beta thalassaemia major is lifelong monthly blood transfusions. What do these need to be combined with and why?
iron chelation
avoid haemochromatosis
Beta thalassaemia major is caused by mutation of what gene?
mutation of Beta globin chain - cant prod HbA (which needs two alpha and two beta chains)
Which element is important in converting clotting factors?
calcium
prothrombin get converted to thrombin. then what happens.
thrombin converts fibrinogen to fibrin
what does plasmin do?
breaks down clots (fibrin) (fibrinolysis)
what is APTT?
activated partial thromboplastin time
- measures activity of lots of clotting factors.
Give me a list of investigations which might be useful in bleeding disorders?
FBC, PT, APTT, D-dimer, LFTs, quantitative fibrinogen assay, vwF antigen
What is the inheritance for haemophilia?
X linked recessive
Which type of haemophilia is more common?
haemophilia A
What clotting factor is affected in haemophilia A?
factor 8 = haemophilia A (commonest)
What clotting factor is affected in haemophilia B?
factor 9 = haemophilia B
What/when is common presentation of haemophilia?
spontaneous bleeding into muscles and joint around 1yr of age.
neonates - intracranial haemorrhage
Haemophilia usually presents at what age?
1 yr olds
What is the treatment for haemophilia A?
recombinant factor 8 concentrate
by IV infusion when bleeding
prophylactic when severe
What is the treatment for haemophilia B?
recombinant factor 9 concentrate
by IV infusion when bleeding
prophylactic when severe
Two complications of haemophilia treatment.
antibodies to factor 8/9
vascular access :/
von Willebrand disease usually presents at what age?
adolescents
What two important things does von willebrand’s factor do?
- facilitates platelet adhesion to damaged to endothelium
- carrier for factor 8
what is the inheritance of von willebrands disease?
autosomal dominant
Adolescent presents with menorrhagia, epistaxis and mucosal bleeding. No purpura. What suspect?
von willbrands disease
What is key investigation in suspected von willebrands disease?
VWF ANTIGEN (low)
what is the treatment for von willebrands disease?
mild - DDAVP (desmopressin)
severe - plasma derived factor 8 concentrate
Name 4 ACQUIRED types of bleeding disorder.
vit K def
liver disease
Immune thrombocytopenia
DIC
Which acquired bleeding disorder causes haemorrahgic disease of the newborn?
vit K def
vitamin K is needed for which clotting factors? :)
10 9 7 2
prolonged prothrombin time
what 3 things can cause vitamin K deficiency?
malnutrition
malabsorption
vit K antagonists.g. warfarin
platelets are destroyed by IgG autoantibodies. what disease is this?
immune thrombocytopenia
when does immune thrombocytopenia tend to present?
age 2-10
often after VIRAL INFECTION
7 yr old presents with petechiae, purpura and superficial bruising after viral infection.
immune thrombocytopenia
define thrombocytopenia.
thrombocytopenia = platelets <150 x10 9/L
What is treatment for immune thrombocytopenia?
usually self limiting! 6-8wks
if major bleed - oral pred
If child has major bleed in immune thrombocytopenia, how do you treat?
oral prednisolone
platelet transfusion if life threatening
What are the symptoms of immune thrombocytopenia?
petechiae, purpura, superficial bruising
80% of immune thrombcytopenia is self-limiting. What % are chronic, a.k.a persistent?
20%
might have to give rituximab
differentials for immune thrombocytopenia ? (x3)
SLE
ALL
aplastic anaemia
diffuse fibrin deposition in microvasculature and consumption of clotting factors and platelets, with severe sepsis / circulatory shock. what’s this?
disseminated intravascular coagulation
what is treatment for DIC?
treat underlying cause
fresh frozen plasma, cryoprecipitate, platelet transfusion
ALL, SLE and aplastic anaemia are all differentials for…
immune thrombocytopenia
List me 2 inherited and 4 acquired bleeding disorders.
inherited - haemophilia, von willebrands disease
acquired - vit K def, liver disease, immune thrombocytopenia, DIC
Name 3 congenital thrombophilias.
- protein C def
- protein S def
- factor V leiden
What is DIC?
diffuse fibrin deposition in microvasculature and consumption of clotting factors and platelets, with severe sepsis / circulatory shock.
Some inherited thrombophilias are protein C def, protein S def, factor V leiden. Name some acquired thrombophilias.
DIC, malignancy, SLE
polycythaemia, Kawasaki
?Acute treatment of thrombosis
LMWH
?Chronic treatment of thrombosis / thrombophilia?
warfarin
