haem Flashcards
what two mechanism can cause decreased RBC production in babies
ineffective erythropoesis (increased destruction, shorter survival) red cell aplasia (no RBC production)
mx IDA
advice: leafy veg and fortified bread
supplement with oral ferrous sulphate (continue 3 months after corrected to replenish iron stores)
monitor regularly to ensure compliance
advice for IDA
S/E of iron - GI irritation, diarrhoea, constipation, impaction, nausea
take iron w/ food or reduce frequency of dose
monitoring for IDA
check FBC after 2-4 weeks, then check at 2-4 months
LIKELY TO BE COMPLIANCE IF NOT RISING
3 causes of red cell aplasia
Congenital - diamond blackfan
transient erythroblastopaenia - can’t make precursors post viral infection (looks like Diamond blackfan but ALWAYS RECOVER)
Parvovirus B19 - only cause problems in kids w/ haemolytic anaemias
Ix in red cell aplasia
low reticulocytes despite low Hb
normal bili
absent RBC precursors in bone marrow
What is a specific test for hereditary spherocytosis
osmotic fragility
mx of hereditary spherocytosis
neonates:
supportive transfusion
folate
phototherapy if jaundiced
infants: transfusions folate splenectomy (but then Abx prophylaxis against encapsulated organsims - h.influenzae, strep pneumonia) query cholecystectomy
triggers for haemolysis in G6PD
INFECTION antimalarials Abx - sulphonamide (cotrimoxazole), chloroquinolones (ciprofloxacin, nitrofurantoin aspirin in high doses toxins - naphthalene, fava beans
why could you get misleadingly elevated G6PD during infections
reticulocytes have higher G6PD
Where is sickle cell mutation
Chr 11
recessive mutation on codon 6 of beta globin gene (valine for glutamine)
What are the 4 types of sickle cell
Sickle cell disease
2 HbS
no HbA (as both beta globin genes are broken)
some HbF
HbSC disease
1 HbS 1 HbC (different point mutation on beta globin gene)
no HbA - both beta globin genes broken
sickle beta thalassemia trait
1 HbS 1 beta thalassemia trait
no HbA
sickle trait
1 HbS
Complications of sickle cell disease
anaemia
infection (increased risk of capsulated organisms and salmonella osteomyelitis - both due to hyposplenism)
vaso-occlusive crises - acute chest syndrome, hand + foot syndrome
acute anaemia - aplastic crsies, SEQUESTRATION CRISES, haemolytic crises
Long term:
STROKE
mx SCD prophylaxis
immunisations against encapsulated organisms
daily penicillin
daily folate
discourage excessive exercise, cold, encourage hydration
mx acute crisis
IV analgesia
rehydrate
infection tx w/ Abx
do exchange transfusion for stroke, acute chest syndrome and priapism
mx chronic
> 3 admissions per year - hydroxycarbamide (encourage HbF) but monitor for low WCC
splenectomy
BM transplant if severe