Cytology and fluid analysis

Question 1

what is cytology?

Answer 1

study of disease through evaluation of cells

Question 2

what are the limitations of cytology?

Answer 2

difficult to achieve final diagnosis on cytology alone
can be non-representative of lesion
often needs to be sent away for analysis

Question 3

what is cytology very good for analysing?

Answer 3

fluids
bone marrow
round cell tumours

Question 4

how can cells be collected for cytology?

Answer 4

fine needle biopsy
imprints/crapes
swabs
aspiration of fluid 
collection of fluid (tracheal wash...)

Question 5

how are mass/organ slides prepared?

Answer 5

squash preparation

Question 6

how are biopsy slides prepared?

Answer 6

imprint

Question 7

how are fluid slides prepared?

Answer 7

smear

Question 8

what is assessed on low power?

Answer 8

quality, cell preservation, distribution
big things (eggs, larvae, fungi, foreign material…)
assess background and cell types
artefacts

Question 9

what is looked at on very high power?

Answer 9

characterisation of nuclear and cytoplasmic detail

better identification of microorganisms

Question 10

what lines the peritoneal, pleural and pericardial cavities?

Answer 10

mesothelium

Question 11

what creates the fluid that lines the mesothelium?

Answer 11

ultra filtrate of blood (low cells and total protein)

Question 12

what is an effusion?

Answer 12

accumulation of fluid in a. body cavity

Question 13

how can effusions be classified?

Answer 13

protein, cell count and cytology

aetiology and composition

Question 14

what are the two effusions based on protein, cell count and cytology?

Answer 14

transudate

exudate

Question 15

what forms a transudate effusion?

Answer 15

imbalances of hydrostatic/oncotic pressure

Question 16

what forms a exudate effusion?

Answer 16

increased vascular permeability due to inflammation

Question 17

what can cause haemorrhagic effusions?

Answer 17

true cavity haemorrhage

iatrogenic blood contamination

Question 18

how can iatrogenic haemorrhagic contamination be confirmed?

Answer 18

uniformly bloody on swirling
clot forms
supernatant clear
no erythrophagocytosis

Question 19

what are the features of a true body cavity haemorrhage?

Answer 19

fluid doesn’t clot
supernatant often haemolysed
erythrophagocytosis

Question 20

how does a chylous effusion appear?

Answer 20

milky/white

Question 21

what body cavity is chylous effusion most commonly seen in?

Answer 21

thorax

Question 22

how can pseudochyle be differentiated from chyle?

Answer 22

pseudochyle has low numbers of triglycerides (white colour from cell debris and cholesterol)

Question 23

how much protein does low protein transudate effusions have in them?

Answer 23

<25g/L

Question 24

what colour are transudate effusions?

Answer 24

clear/colourless

Question 25

what causes low protein transudate effusions?

Answer 25

(hypoalbuminaemia) decreased oncotic pressure due to low serum protein

Question 26

how much protein does high protein transudate effusions have in them?

Answer 26

>25g/L

Question 27

what colour is high protein transudate effusions?

Answer 27

colourless to amber to pink

Question 28

what causes high protein transudate effusions?

Answer 28

increased hydrostatic pressure (congestive heart failure, thrombi, neoplasm)

Question 29

what is another name for high protein transudates?

Answer 29

modified transudates

Question 30

how do exudate effusions appear?

Answer 30

turbid | yellow/brown/bloody

Question 31

what is the main cell in exudates?

Answer 31

neutrophils (inflammation)

Question 32

what are the two forms of exudate?

Answer 32

septic | non-septic

Question 33

what are septic exudates classified by?

Answer 33

``` intracellular organisms (not always present) degenerate neutrophils ```

Question 34

what are non-septic exudates classified by?

Answer 34

non-degenerate neutrophils

Question 35

what can cause septic exudates?

Answer 35

penetrating wound foreign bodies GI perforation/ischeamia haematogenous route

Question 36

what can cause non-septic exudates?

Answer 36

``` ruptured gall bladder rupture urinary bladder necrotic tumour pancreatitis FIP ```

Question 37

what are the indications for arthrocentesis?

Answer 37

``` joint disease of unknown aetiology diseases of multiple joint suspected infective arthritis pyrexia of unknown origin monitoring therapeutic response ```

Question 38

what colour is normal synovial fluid?

Answer 38

clear/pale yellow

Question 39

how do synovial fluid in the presence of inflammation look?

Answer 39

yellow turbid