cytology Flashcards
(26 cards)
what is an effusion
accumulation of fluid in a body cavity
define transudate
effusion caused by imbalances of hydrostatic/oncotic pressure
define exudate
effusion caused by increased vascular permeability due to inflammation
what are causes of haemorrhagic effusions
iatrogenic blood contamination
splenic tap
true cavity haemorrhage
how do you know if blood contamination is iatrogenic
initially clear then bloody
should clot
can see platelets
no erythrophagocytosis
how do you regcognise a true body cavity haemorrhage
doesent clot
supernatant often haemolysed
erythrophagocytosis
no platelets
how does a chylous effusion look like and what does it consist of
milky white/pink
composed of chylomicrons, high protein (>25g/l) and high triglyceride (>1,13mmol/l)
chylous effusions are formed due to lymphatic drainage impairment or leakage. what are possible causes of this
heart disease, trauma, neoplasia, idiopathic
how do you differentiate pseudochyle from normal chyle
has normal triglyceride levels
what is responsible for the colour of pseudochyle and in what patients is it seen
colour due to cell debris, protein and cholestrol.
seen in cats with cardiac failiures
describe a low protein transudate
clear and colourless with low protein (>25g/l) and low cell count (1.5x10^9/L)
the cells present are mainly monocytes and macrophages
what causes a low protein transudate
decreased in oncotic pressure due to low serum protein.
cause leakage of fluid
what are causes of low protein transudates
hypoalbuminaemia, protein loosing entropathy, protein loosing nephropathy, reduced protein production due to liver disease
describe high protein transudate
colourless to amber
high protein (>25g/l)
moderate to high cell count
what causes high protein transudate
increased hydrostatic pressure
congestive heart failiure, thrombi or neoplasia obstructing large veins (vena cava)
what are features of high protein transudate on cytology
mixed population of cells
more neutrophils than transudate
describe exudates
yellow-brown colour and turbid
high nucleated cell count
high protein
cells present are mostly neutrophils
what causes exudates and what are the two forms
increased vessel permeability
septic and non septic forms
how to differentiate between septic and non septic exudate
septic contains degenerate neutrophils and sometime intracellular organsims are visible
what are possible causes of septic exudates
penetrating wound
foreign body
GI perforation or ischaemia
haematogenous route
what are possible causes of non septic exudates
ruptured gall bladder ruptured urinary bladder Necrotic tumor pancreatitis FIP
describe the exudate of a cat with wet FIP
sticky yellow and frothy
high protein
low albumin:globulin ratio
few macrophages
what colour is bile peritonitis
GREEN!
definitive test is exudate bilirubin concentration higher than plasma bilirubin
what is the definitive indicator of bladder rupture
exudate [creatinine] higher than plasma [creatinine]
use this as [urea] equalises between fluid and plasma
