Diagnosis of Effusions Flashcards
(44 cards)
What is an effusion?
Increased amount of fluid in abdominal or thoracic cavity
Is effusion considered a disease?
No - not a disease in itself
Indicative of a pathologic process affecting either fluid production and/or removal
What kind of tube should you use to collect fluid for cytology and protein analysis?
EDTA - fluid will not clot
What kind of tube should you use to collect fluid for biochemical tests and culture?
Serum (plain - NOT GEL)
What does TNCC mean? What is the normal fluid level in small animals?
Total nucleated cell count
Normal level <3 x 10^9/L
What is “normal” TP (total protein) in small animals?
TP = 25-30 g/L
Give some features of normal fluid in small animals? Color, turbidity, volume, normal cells
Low volume, Clear, Straw colored
Creates thin film on serosal surfaces
Mesothelial cells (line body’s organs) + macrophages normal
What are the classifications of effusions? How are they classified?
Transudate, Modified Transudate, Exudate, Hemorrhage
Classified based on cell counts and TP
Transudate: TP, TNCC, Turbidity, SpG
Typical cell type and # found in transudate
TP: <25 g/L, TNCC <0.5 x 10^9/L
Clear (like water), SpG <1.018
Low cellularity, mesothelial cells/macrophages
Low # non-degenerate neutrophils
What is Transudate?
Transudates are fluids that pass through a membrane or squeeze through tissue or into the EXTRACELLULAR SPACE of TISSUES. Transudates are thin and watery and contain few cells or PROTEINS.
What causes transudates?
Combination of low colloid osmotic pressure (low protein levels) and increased hydrostatic pressure
- Hypoalbuminemia
- Secondary to GI, Hepatic or Renal disease
- Protein-losing nephropathy
How does hepatic cirrhosis/portal hypertension cause transudate formation?
Secondary to hepatic fibrosis/cirrhosis
Consistent damage to the liver causes fibrosis of healthy tissue, liver cannot filter blood/toxins the way it should
Buildup of blood traveling from portal system (digestive system), which backs up in the portal vein (increased pressure in vein)
Formation of verices (secondary collateral circulation)
Production of local vasodilators to compensate for increased fluid volume –> Lowered BP/SVR –> RAAS kicks in –> retention of sodium/fluid
Results in fluid (low protein lymph) leaking out of vasculature and into the abdominal cavity (ascites)
Also results in porto-systemic shunts (between spleen/kidney and systemic circulation, meaning that non-filtered blood that could potentially contain toxins enters the systemic vasculature)
What kind of effusion is this?
Modified Transudate
What kind of effusion is this?
Transudate
What kind of effusion is this?
Exudate
How does modified transudate compare to transudate?
TP 25-50 g/L (higher)
Serosanguinous color, cloudy (more cellular)
TNCC anywhere from 0.3 - 7 x 10^9/L (higher)
SpG 1.018 - 1.030 (higher)
Mesothelial cells, macrophages, non-degenerate neutrophils, small lymphocytes
What are the causes of modified transudate?
Cardiac failure = Chronic passive congestion = hepatic venous obstruction –> Leakage of high protein lymph from the liver
Exudate: TP, TNCC, Turbidity, SpG
Typical cell type and # found
TP: >30 g/L
TNCC > 3.0 x 10^9/L
SpG >1.018
Neutrophils (degenerate or not)
Macrophages, Lymphocytes, Eosinophils
What qualities characterize an exudate?
Very active inflammatory process
High TNCC and protein
turbid - red, yellow or white fluid
How does an exudate form?
VERY well defined process
Occurs due to active inflammation
- bite, wound, infections
- inflammation of pleural/abdominal cavities or their linings
- Infection of long-standing pleural fluid
- Neoplasia (necrotic, inflammatory process)
Cytokine action –> leaky capillaries –> plasma proteins get across barrier –> free movement of high protein fluid
What is FIP and what kind of effusion can it cause? What is the difference between wet and dry FIP?
Non-septic exudate (non-degenerate neutrophils, no bacteria) or Modified transudate (depends on cellularity) - usually both at different times of disease
High protein (exudate)
Globulins > 0.81 on fluid
Caused by feline coronavirus
Wet FIP = exudative (accumulation of fluid in abdominal cavity as a result of vasculitis)
Dry FIP = no fluid accumulation, but granuloma formation on internal organs
How does coronavirus cause FIP?
Coronaviruses are common and found in the faeces of many cats. In most cats, infection causes no signs or just mild diarrhoea that resolves without treatment. However, occasionally, the virus mutates (changes) inside a cat, and if their immune system reacts in a certain way, they could develop a disease called FIP. This is important, as finding coronavirus in a cat does not mean they have FIP, and it is not possible to consistently tell the difference between a coronavirus causing FIP and one causing no signs at all by just finding the virus itself.
What kind of effusion is this? What can this kind of be caused by (cats)?
What kind of effusion is this?
