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Flashcards in lecture 6 Deck (28):

What is increased when an animal is responding to anemia?

Howell-Jolly bodies


why might there be a body cavity effusion

Causes include:
Impaired absorption
Abnormal vascular pressure
Decreased albumin concentration in the blood


Reasons for centesis and aspiration of fluids from body cavities?

Excessive fluid accumulation
Suspected lesion with exfoliation of cells
- Increased fluid in a body cavity is not a disease itself, but rather a sign of disease or pathological process 


what is centesis

introduction of a needle (catheter) into a body cavity or organ for collection (usually aspiration) of fluid


what should be used for collection for Peritoneal, pericardial and pleural fluid

EDTA tube used for total nucleated cell count (TNCC), total protein (TP) and cytological evaluation
Red top tube used for biochemical parameters (e.g. creatinine)
Fluid collected into culture-transport medium if culture requested (aerobic and anaerobic)


different colors mean:

a) Serum or plasma - light or dark yellow
b) Erythrocytes - red, dark red, or reddish brown
c) Leukocytes - white, cream, yellow, gray or green
d) Chyle - milky white, peach or pink
e) Bilirubin - yellow, orange, red or brown


What contributes to turbidity in a fluid sample?

cells/ protein/bacteria


How would we determine a total nucleated cell count (TNCC) with relatively clear fluids?

if relatively clear we can run through a blood machine, if not or there might be pus don't bother


what should we know about TP concentration

refractometer is method of choice in pericardial, pleural and peritoneal fluid (centrifuge and use supernatant if fluid is opaque)
The TP of chylous and lipemic fluids often cannot be determined by refractometry or an automatic chemistry machine


what might be miscellaneous finding

Glove powder (cornstarch)
Basket (smudge) cells – caused by excessive pressure on cells during slide prep or increased cell fragility in some effusions e.g. certain effusions chylous and septic


what should we do for smear prep

1. Smears should be made ASAP after collection of fluid into EDTA
2. Concentration techniques may be needed – 2,000 RPM for 5 minutes
3. Supernatant analyzed for TP (other biochemical parameters if required) and discarded
4. Mix sediment with a small amount of supernatant
5. Blood smear, compression smear and line smear techniques – try a combination if there is sufficient cell sediment


what should be included for smears for external lab cytology

Direct smears
Stained (optional) and unstained air-dried smears
The sample in the EDTA tube
Red top tube for culture or swab in transport medium
Do not ship smears with formalin jars


what are the classifications if effusinons

Modified transudates
Generally total protein is the most important criterion to differentiate transudates from modified transudates

Cellularity is most important for differentiating modified transudates from exudates


what is a transduate

Transudate = excess accumulation of normal fluid (filtrate of plasma) in any body cavity or space.
Usually due to decreased plasma oncotic pressure (hypoalbuminemia)
< 2.5 g/dl protein and < 1500 nucleated cells/ul


what is a modified transudate

Modified transudate - A transudate that remains in a body cavity for a period of time causes irritation to the lining of that cavity
Results: increased cellularity (mainly proliferation of mesothelial cells); increase in TP (usually due to fluid leakage from lymphatics or blood vessels)
TNCC - 1000 - 7000 cells/ul
TP concentration - 2.5-7.5 g/dl


what is an exudate

TNCC and TP concentration - generally much higher than transudates
Characteristics of an exudate:
TP is > 3.0 g/dl
High TNCC or >7000 cells/µl
Predominant cell type depends on cause
Inflammatory exudates - neutrophil generally predominates with variable numbers of macrophages and lymphocytes.


what are characteristics of non-septic exudate

Characteristics of non-septic exudate:
Turbid fluid with variable colour
>3.0 g/dl of protein
7,000 + cells/µl


how are septic exudates characterized

Turbid fluid with variable colour
> 3.0 g/dl of protein
7,000 + cells/µl


what is hemorrhagic effusion

Causes: trauma, surgery, infarction of the intestine, neoplasia, clotting abnormalities
Differentiation of hemorrhagic effusion and aspiration of an organ (liver/spleen) or blood vessel is important


how is recent hemorrhage characterized

1.Clear supernatant fluid and red sediment
2.Protein and cell count values similar to those of peripheral blood.
3.Intact erythrocytes
4.Leukocytes of similar morphology and distribution as those in peripheral blood
5. Platelet aggregates


how is long-standing hemorrhage characterized

1.Distortion and perhaps degeneration of RBCs and leukocytes
2.Supernatant may be pink due to hemolysis early on but then becomes yellowish (Hb breakdown)
3.Absence of platelets
4.Macrophages with phagocytized RBCs and hemosiderin


what stain can be used for hemosiderin

crushin blue


what is FIP

Feline Infectious Peritonitis (FIP)

Non-septic exudate (pleural, peritoneal fluid)
odorless, straw-colored to golden, tenacious
may contain flecks or fibrin strands
high TP concentration (3.5 to 8.0 g/dl)

TNCC (can be up to 23,000 or more cells/ul)

Mainly non-degenerate neutrophils (60-80%) and lesser numbers of macrophages, lymphocytes and occasionally plasma cells.


what is equine colic peritoneal fluid

Peritoneal fluid via abdominocentesis (fluid on left is abnormal and fluid on right is normal peritoneal fluid from horses)


what is uroperitoneum

-Urine in the abdominal cavity - causes a non-septic exudative effusion
-Very acute rupture -> elevated urea nitrogen in the abdominal fluid (compared to blood urea nitrogen levels); urea nitrogen is rapidly reabsorbed by the lining tissues and levels soon are equal to those in blood (generally within 24 hours).
- Creatinine remains > blood levels for longer periods. Therefore, measurement of the creatinine level is more reliable than measurement of the urea nitrogen level.


what are chylous effusions

May occur secondary to many disease processes such as trauma, heart disease, inflammation and neoplasia.
-occurs in the thorax and is generally bilateral in cats and dogs.


what is effusion in heart failure

Ascites may develop secondary to heart failure
Pleural effusion may also develop secondary to cardiac disease
The fluid is a modified transudate
---pink to red and cloudy fluid
2.5-5.0 g/dl protein
300-5500 cells/ul
Variable numbers of RBCs, non-degenerate neutrophils, mesothelial cells, macrophages, occasionally eosinophils and lymphocytes
Cytology is not diagnostic of heart failure


what should we know about neoplasia effusions

Effusions associated with neoplasia are variable
Depend on type of tumour
Most non-exfoliative tumours cause a modified transudate
Most tumours that exfoliate cells cause an exudative effusion