Anaemia Flashcards
Define anaemia?
Low Hb or low RBCs for perons sex and age
Three main categories of anaemia?
1) erthropoiesis (can’t make RBC)
2) losing RBC
3) RBC being destroyed (haemolytic anaemia)
Primary and secondary erthropoiesis anaemia causes?
primary - Fancoi’s anaemia/phenytoin
seconary - malgignancy (lymphoma, leukaemia), infection (EBV/ Hep C/ TB/ HIV/ CMV/ parovirus B19)
Causes of losing RBC anaemia?
Menstruation, blood loss
Inherited causes of chronic haemolytic anaemia?
Hereditary spherocytosis
Hereditary elliptocytosis
G6Pd deficiency
Sickle cell anaemia
Thalassaemia
Acquired causes of chronic haemolytic anaemia?
Autoimmune haemolytic anaemia
Alloimmune haemolytic anaemia (e.g., transfusions reactions and haemolytic disease of newborn)
Paroxysmal nocturnal haemoglobinuria
Microangiopathic haemolytic anaemia
Prosthetic valve-related haemolysis
Features of haemloytic anaemia?
Anaemia
Splenomegaly (the spleen becomes filled with destroyed red blood cells)
Jaundice (bilirubin is released during the destruction of red blood cells)
What are key investigations for haemolytic anaemia?
Full blood count shows a normocytic anaemia
Blood film shows schistocytes (fragments of red blood cells)
Direct Coombs test is positive in autoimmune haemolytic anaemia (not in other types)
Describe hereditary spherocytosis, presentation, key findings and treatment?
fragile, sphere-shaped red blood cells, break down easily in spleen. autosomal dominant
presentation: anaemia, jaundice, gallstones and splenomegaly. Aplastic crisis in parovirus presence. Likely pos FH.
key findings: raised MCH, raised reticulocytes, spherocytes on blood film.
treatment: folate supplements, blood transfusion and splenectomy. cholecystectomy if gallstones are issue.
Describe hereditary elliptocytosis, presentation, key findings and treatment?
similar to spherocytosis but RBCs = elipse shaped. autosomal dominant
Describe G6PD deficency, presentation, its triggers, key findings and treatment?
defect in G6PD enzyme which protects RBCs from oxidative damage. X-linked recessive. Mediterranean, asian, afriican pts.
presentation: jaundice, gallstones, anaemia, splenomgely, Heinz bodies on blood film.
triggers: infection, drugs (ciprofloxacin, sulfonylureas (e.g., gliclazide) and sulfasalazine), fava beans
Describe autoimmune haemolytic anaemia (warm and cold), presentation, key findings and treatment?
antibodies created against RBCs
warm AIHA: occurs at warm temps. idiopathic. IgG antibodies.
cold AIHA: occurs <10 degrees. cause RBC agglutination. Causes secondary to lymphoma, leukaemia, SLE, infections (mycoplamsa, EBV, CMV, HIV)
treatment: blood transfusion, pred, rituximab, splenectomy
Describe two types of Alloimmune Haemolytic Anaemia
antibodies produced due to foreign RBCs.
causes: blood transfusion reactions and haemolytic disease of the newborn
what is haemolytic disease of the newborn?
When maternal antibodies destory foetal RBCs
Mother = rhesus D neg; foetus = rhesus D pos
Mother can become exposed to foetus blood (sensitisation event) = mother produces anti-D antibodies against rhesus D antigen. Antibodies can cross to baby = haemolysis.
Sensitisation event prevented with anti-D prohylaxis in rhD neg women.
Describe Prosthetic valve-related haemolysis, presentation, key findings and treatment
Complication of bioprosthetic and metallic valvue replacement.
Cause: turnbulent flow of valvues and shearing of RBCs. They break down.
mangement: monitor, oral iron and folate, blood transfusions, revision surgery
Describe sickle cell anaemia, pathophys, relation of malaria and treatment?
abnormal Hb (HbS) = sickle cell shaped RBCs. Autosomal recessive of beta-globin on chr-11 (x2 = disease, x1 = trait)
relation to malaria: less severe malaria if have sickle cell trait
Causes of microcytic anaemia?
TAILS
Thalassemia
Anaemia of chronic disease
iron deffiency
Lead poisoning
Sideroblastic anaemia
Causes of normocytic anaemia?
3As and 2Hs
aplastic anaemia (abnormal bone marrow)
anaeamia of chronic disease (renal failure, low EPO)
acute blood loss
haemolytic anaemia
hypothyroidism
Causes of macrocytic anaemia?
Megablastic: B12/folate defficency
Normoblastic: HARD L
Hypothyroidism
alcohol
Reticulocytosis
drugs
liver disease
What factors could hinder anaemia treatment?
decreased absoprtion in stomach/intestine due to:
decreased stomach acid
loss of intrinsic factor (pernicious anaemia)
coeliac disease
Presentation of anaemia, signs and symptoms?
tiredness
SOB
headaches
dizziness
pale skin
conjunctival pallor
tachycardia
raised resp rate
Specific signs and symptoms for iron deficiency?
Pica
hair loss
koilonychia
angular cheilitis
atrophic glossitis
brittle hair and nails
Types of cells seen on blood film for iron deficency?
Target and pencil cells
Specific and non specific signs of haemolytic anaemia?
Pallor of conjunctive/Palmar Crease
Tachy + Flow Murmurs
Cardiac Failure
Venous Thromboembolism
Pre-Hepatic Jaundice - Unconjugated hyperbilirubinaemia (due to increased breakdown of RBC)
Splenomegaly - Extramedullary Haematopoiesis
Dark Urine - Haematopoiesis (intravasular Hameolysis)
Gallstones - Right Upper Quadrant Pain
In haemolytic anaemia, reticulocytes unconjugated bilirubin and serum lactate dehydrogenase (LDH) is all high. why?
Reticylocytes - attempt to replace broken down RBCs
UC B - break down of RBC released bilirubin
LDH - non specific marker of cell turnover
What is direct coombs test?
Identifies cells coated with antibody/complement components, suggesting autoimmune cause of haemolysis
What are haptoglobins and their presence in haemolytic anaemia?
bind free Hb, will be low/absent in haemolysis as lots of free Hb in circulation
What is hemosiderin and its relevance in haemolytic anaemia?
free Hb in kidney tubules. detected by prussian blue staining
Treatment for haemolytic anaemia?
Autoimmune = steroids (and IV Ig)
Sickle cell = hydroxycarbamide
RC transfusions
What is thalassaemia?
autosomal recessive
loss in alpha or beta chains of Hb
Types of thalassaemia and presentation?
β Major:
- Severe Anemia
- Jaundice
- Hepatosplenomegaly
- Bone deformities
⍺ Major:
- Fetalis Hydrops [In utero heart
failure :’( ]
β & ⍺ Trait:
- mild microcytic anaemia (maybe
more severe in ⍺)
- asymptomatic
Investigations for thalassaemia?
low MCV
low MCH
high reticylocytes
- Haemoglobin electrophoresis reveals partial or complete absence of HbA.
Cannot detect ⍺ trait
Genetic analysis required for ⍺ trait
Treatment for thalassaemia?
Major = lifelong transfusions
splenectomy
allogenic bone marrow transplant
trait = give iron if deficient
genetic counselling
What is sickle cell disease?
autosomal recessive
defect beta chains for Hb (2 beta and 2 alpha chains needed for normal Hb)
Presentation of sickle cell disease?
- Chronic haemolytic
anaemia - Haemolytic crises
- Painful infarctive crises
- Aplastic crises
- Splenic complications
- Infection susceptibility
- Acute chest syndrome
- Cerebrovascular
ischaemia - skin ulceration
- proliferative retinopathy
Hb forms crystals in low O2 so agglutinates banana-shaped RBCs
Investigations of sickle cell?
normocytic anaemia
reticuloysis
blood film:
sickle cells, target cells, Howell-Jolly bodies
Hb electrophoresis: HbS, some HbF and no HbA
Treatment for Sickle cell anaemia?
prophylaxis:
* avoid precipitating
factors
* folic acid
* pneumococcal
vaccine; regular oral
penicillin
* hydroxycarbamide
- crises:
- analgesia (opiates),
rest, rehydration,
oxygen +/- antibiotics - blood transfusion/
exchange transfusion - stem cell
transplantation
