Transudate
Transudate is extravascular fluid with low
Transudate vs. exudate
| Transudate vs. exudate | ||
|---|---|---|
| Transudate | Exudate | |
| Main causes | ↑ colloid
osmotic pressure |
Inflammation-Increased vascular permeability |
| Appearance | Clear[1] | Cloudy[1] |
Specific gravity |
< 1.012 |
> 1.020
|
| Protein content | < 2.5 g/dL |
> 2.9 g/dL[2]
|
| fluid protein/ serum protein |
< 0.5 | > 0.5[3] |
| SAAG = Serum [albumin] - Effusion [albumin] |
> 1.2 g/dL | < 1.2 g/dL[4] |
| fluid LDH upper limit for serum |
< 0.6 or < 2⁄3 | > 0.6[2] or > 2⁄3[3] |
| Cholesterol content | < 45 mg/dL | > 45 |
| Radiodensity on CT scan | 2 to 15 HU[5] | 4 to 33 HU[5] |
There is an important distinction between transudates and exudates. Transudates are caused by disturbances of hydrostatic or colloid osmotic pressure, not by inflammation. They have a low protein content in comparison to exudates and thus appear clearer.[6]
Levels of lactate dehydrogenase (LDH)[7] or a Rivalta test can be used to distinguish transudate from exudate.[citation needed]
Their main role in nature is to protect elements of the skin and other subcutaneous substances against the contact effects of external climate and the environment and other substances – it also plays a role in integumental hygiene.[citation needed]
Pathology
The most common causes of pathologic transudate include conditions that:[citation needed]
- Increase hydrostatic pressure in vessels: left ventricular heart failure,
- Decrease oncotic pressure in blood vessels:
- Cirrhosis (Cirrhosis leads to hypoalbuminemia and decreasing of colloid oncotic pressure in plasma that causes edema)
- Nephrotic syndrome (also due to hypoalbuminemia caused by proteinuria).
- Malnutrition (hypoalbuminism)
See also
References
- ^ a b The University of Utah • Spencer S. Eccles Health Sciences Library > WebPath images > "Inflammation".
- ^ PMID 9106577.
- ^ PMID 4642731.
- PMID 2152757.
- ^ PMID 24100060.
- ^ The University of Utah • Spencer S. Eccles Health Sciences Library; WebPath images "Inflammation".
- ^ "IM Quiz: Pleural Adenocarcinoma". Archived from the original on 2008-09-16.