red cells Flashcards
substances require for production
iron copper cobalt manganese B12 folic acid thiamine Vit B6 CE aminoacids Erythropoietin, GM-CSF Thyroxine, androgen
Red cell breakdown
occurs in the reticuloendothelial system macropahges in spleen liver lymph nodes 120 days Globin AA reutilised Haem Iron recycled Haem- biliverdin- bilirubin
genetic defects
in red cell membrane
in metabolic pathways
in haemoglobin
skeletal proteins
responsible for maintaining red cell shape and deformability
defects can lead to increased cell destruction
most common membrane disorder
hereditary spherocytosis autosomal dominant defects in 5 different structural proteins -Ankyrin -Alpha Spectrin -Beta Spectrin -Band 3 -Protein 4.2
clinical presentation
anaemia jaundice splenomegaly pigment gallstones treatment folic acid transfusion splenectomy
rare membrane disorders
hereditary elliptocytosis
hereditary pyropoikilocytosis
red cell enzymes
glycolysis
provides energy
Pentose Phosphate shunt
-protects from oxidative damage
Glucose 6 phosphate deficiency
commones disesse cusing enzymopathy in the world Oxidative damage confers protection against malaria X Linked affects males female carriers
G6PD defieciency
blister/ bite cells clinical features variable anaemia neonatal jaundice splenomegaly pigment gallstones drug broad bean or infection precipated jaundice and anaemia \: intravascular hemolysis if sick red cell count can be infected
pyruvate kinase deficiency
reduced ATP increased 2 3 DPG anaemia jaundice gallstone
4 alpha genes
chromosome 16 ( 2 from one parent)
2 Beta genes
chromosome 11
normal adult
HbA -97
Hb A2 -2
Hb F -1
sickle cell disease
point mutation in beta chain Glu replaced by Val
crystal form through deoxygenation tension
hemolysis
coagulation activation
dysregulation of vasomotor tone by vasodilator mediators
->
vaso- occlusion
presentation
stroke, brain sickling in lungs, bone early childhood sickling in spleen auto infarction- hyposplenic Bone pain presentation abnormal spleen immunity low high red cell turnover, parvovirus severe anaemia requiring transfusion sequestraion crises- enlarged liver spleen
painful crisis
severe pain often requires opiates -Analgesia should be given within 30 mins of presentation -Effective analgesia by 1hour - Avoid pethidine Hydration Oxygen Consider antibiotics
management
Life long prophylaxis Vaccination Penicillin (and malarial) prophylaxis Folic acid Acute Events Hydration Oxygenation Prompt treatment of infection Analgaesia Opiates NSAIDs - Blood transfusion
disease modifying drugs
hydroxycarbamide
blood transfusion
episodic or chronic
alloimmunisation
iron overload
thalassemia
reduced or absent globin chain
mutations or deletions
beta thalassaemia major
severe anaemia -presents at 3-6 months expansion of ineffective bone marrow bony deformities splenomegaly growth retardation
chronic transfusion
iron overloading
death in 2nd or 3rd decades due to heart/ liver/ endocrine failure if iron loading not treated
beta thalassemia ajor treatment
iron chelation therapy
bone marrow transplant
