Transudate

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Transudate is extravascular fluid with low protein content and a low specific gravity (< 1.012). It has low nucleated cell counts (less than 500 to 1000 /microliter) and the primary cell types are mononuclear cells: macrophages, lymphocytes and mesothelial cells. For instance, an ultrafiltrate of blood plasma is transudate. It results from increased fluid pressures or diminished colloid oncotic forces in the plasma.

Contents

Transudate vs. exudate

Transudate vs. exudate
Transudate Exudate
Main causeshydrostatic
pressure
,
colloid
osmotic pressure
Inflammation-Increased
vascular permeability
AppearanceClear [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 < 23> 0.6 [2] or > 23 [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 ]

See also

Related Research Articles

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<span class="mw-page-title-main">Hepatic hydrothorax</span> Medical condition

Hepatic hydrothorax is a rare form of pleural effusion that occurs in people with liver cirrhosis. It is defined as an effusion of over 500 mL in people with liver cirrhosis that is not caused by heart, lung, or pleural disease. It is found in 5-10% of people with liver cirrhosis and 2-3% of people with pleural effusions. It is much more common on the right side, with 85% of cases occurring on the right, 13% on the left, and 2% on both. Although it is most common in people with severe ascites, people with mild or no ascites have had the condition. Symptoms are not specific and mostly involve the respiratory system.

References

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  3. 1 2 Light R, Macgregor M, Luchsinger P, Ball W (1972). "Pleural effusions: the diagnostic separation of transudates and exudates". Ann Intern Med. 77 (4): 507–13. doi:10.7326/0003-4819-77-4-507. PMID   4642731.
  4. Roth BJ, O'Meara TF, Gragun WH (1990). "The serum-effusion albumin gradient in the evaluation of pleural effusions". Chest. 98 (3): 546–9. doi:10.1378/chest.98.3.546. PMID   2152757.
  5. 1 2 Cullu, Nesat; Kalemci, Serdar; Karakas, Omer; Eser, Irfan; Yalcin, Funda; Boyaci, Fatma Nurefsan; Karakas, Ekrem (2013). "Efficacy of CT in diagnosis of transudates and exudates in patients with pleural effusion". Diagnostic and Interventional Radiology. 20: 116–20. doi:10.5152/dir.2013.13066. ISSN   1305-3825. PMC   4463296 . PMID   24100060.
  6. The University of Utah • Spencer S. Eccles Health Sciences Library; WebPath images "Inflammation".
  7. "IM Quiz: Pleural Adenocarcinoma". Archived from the original on 2008-09-16.