Polycytaemia (Yr 3) Flashcards
what is erythrocytosis also known as?
polyctaemia
what is erythrocytosis?
any increase in PCV, RBC count or haemoglobin
what is a relative erythrocytosis?
increased RBC count due to changes in plasma water (dehydration) or RBC redistribution (splenic contractions)
what is an absolute erythrocytosis?
true increase in RBC numbers due to erythropoiesis
what breeds have a higher PCV naturally?
sighthounds
how can you determine in erythrocytosis is due to dehydration?
clinical signs of dehydration
increase total protein/albumin
what are the two causes of absolute erythrocytosis?
secondary (increased erythropeotin)
primary (not due to increased erythropeotin)
what are the two types of secondary absolute erythrocytosis?
appropriate (response to hypoxia)
inappropriate (not response to hypoxia)
what can cause inappropriate secondary absolute erythrocytosis?
renal tumours of lesions causing a localised renal hypoxia
non-renal tumours producing erythropoietin-like substances
what is the cause of primary absolute erythrocytosis?
myeloproliferative disorder (leukaemia)
what are the clinical signs of primary absolute erythrocytosis?
hyperviscosity of blood
how is absolute erythrocytosis treated?
remove underlying cause
stabilised with phlebotomy