829
edits
Changes
no edit summary
*'''High cells''' and '''low protein''' OR '''Low cells''' and '''high protein'''
{{unfinished}}
*Yellow to serosanguinous, turbid
==Description==
Modified transudates are a type of effusion whose cell count and protein content are intermediate between a [[Transudate|transudate]] and an [[Exudate|exudate]]. In some cases, modified transudates may represent a transitional stage before the development of an exudate (as with uroabdomen, which begins as a modified transudate but develops into a chemical exudative peritonitis over time). Modified transudates arise as a result of disruptions to the endothelium (as with vascultis) or imbalances in the Starling forces. Common causes include:
*'''Increased vascular hydrostatic pressure''' resulting from inappropriate activation of the renin-angiotensin-aldosterone system (RAAS) in '''portal hypertension''' or '''congestive heart failure'''.
*'''Vasculitis''', caused by '''feline infectious peritonitis virus''' (FIPV) or '''neoplasia'''. For further discussion of the effusion encountered with FIP, see [[Feline Infectious Peritonitis|here]].
*'''Strangulation of abdominal or thoracic organs''' may lead to the production of a modified transudate (which will develop into an exudate if untreated). This may occur with '''lung lobe torsion''', '''torsion of the spleen''' or of a liver lobe or if part of the liver becomes strangulated within a [[Diaphrgamatic Rupture|'''diaphragmatic rupture''']].
*'''[[Chylous Effusion|Chylous effusions''']] are sometimes considered to be a type of modified transudate.
==Diagnosis==
===Clinical Signs===
Effusions may occur in any of the major body cavities, causing:
*'''Ascites''', often of a high volume. An abdominal fluid thrill will often be palpable and the abdomen may appear to be grossly swollen.
*'''Hydrothorax''' causing tachypnoea and dyspnoea if severe. Dullness will be evident on thoracic percussion if a pleural effusion has developed and the heart sounds will be muffled on auscultation.
*'''Pericardial effusion''', which may be sufficiently severe to cause cardiac tamponade and right-sided heart failure. The heart sounds will be muffled on auscultation and there may be hepatojugular reflux, a jugular pulse or signs of left-sided forward failure.
*In large animals (horses and cattle), '''ventral oedema''' is much more likely to be encountered than ascites in animals with congestive heart failure.
===Diagnostic Imaging===
Effusions are easily diagnosed by '''ultrasonography''' and this modality may also be used to guide fine needle aspiration to obtain a sample of the fluid. Effusions also produce a distinctive pattern on '''plain radiograph'''s:
*With pericardial effusion, the heart may appear to be generally enlarged with a globular shape. There may be a crisp cardiac silhouette (as the heart is moving within a stationary bag of fluid) and a hypovascular lung pattern due to pulmonary underperfusion.
*With ascites, there is a loss of serosal detail due to the presence of fluid in the abdominal cavity. This appearance may also occur with large abdominal masses and in emaciated animals.
*With pleural effusions, the lung lobes are contracted and lobulation is evident. Areas of peripheral radio-opacity should be evident, especially peripherally in the chest.
===Cytology===
Definitive diagnosis of any effusion relies on collection of a sample and cytological analysis. A refractometer can be used to measure the specific gravity of the fluid. The following features are typical of a modified transudate:
*Yellow to serosanguinous, turbid fluid
*Specific gravity 1.018 - 1.030
*Specific gravity 1.018 - 1.030
*Total protein 25 - 50g/L
*Total protein 25 - 50g/L
*Nucleated cells 0.3 - 5.5 x10e9/L (up to 7 x 10e9/L)
*Nucleated cells 0.3 - 5.5 x10e9/L (up to 7 x 10e9/L), of which the majority are [[Mesothelial cells|mesothelial cells]], [[Macrophages|macrophages]], non-degenerate neutrophils and small [[Lymphocytes|lymphocytes]].
*If the effusion has been caused by a neoplasm, exfoliated cells may be observed in the fluid but this is unlikely to be useful in identifying the origin of the tumour.
[[Category:Effusions]]
[[Category:Effusions]]
[[Category:To_Do_-_James]]
[[Category:To_Do_-_James]]
[[Category:Dog]][[Category:Cat]][[Category:Horse]][[Category:Cattle]]