transudates การใช้

• There is an important distinction between transudates and exudates.
• This engorgement of blood vessels increases the volume of transudate from the vaginal walls.
• Transudates are caused by disturbances of hydrostatic or colloid osmotic pressure, not by inflammation.
• Levels of lactate dehydrogenase ( LDH ) or a Rivalta test can be used to distinguish transudate from exudate.
• Transudate has a neutral pH, so increases in its production can temporarily shift vaginal pH to be more neutral.
• The SAAG may be a better discriminant than the older method of classifying ascites fluid as a transudate versus exudate.
• The OraSure test works by taking not saliva, but something called oral mucosal transudate, from a person's cheek.
• This test was originally developed by the Italian researcher Rivalta around 1900 and was used to differentiate transudates and exudates in human patients.
• The test uses a sponge-like device to collect a different substance ( oral mucosal transudate ) found in cheek and gum tissue.
• The " serum-ascites albumin gradient " ( SAAG ) is probably a better discriminant than older measures ( transudate versus exudate ) for the causes of ascites.
• More recent studies have examined other characteristics of pleural fluid that may help to determine whether the process producing the effusion is local ( exudate ) or systemic ( transudate ).
• Necropsy examination will usually show changes in the bursa of Fabricius such as swelling, oedema, haemorrhage, the presence of a jelly serosa transudate and eventually, bursal atrophy.
• An accurate diagnosis of the cause of the effusion, transudate versus exudate, relies on a comparison of the chemistries in the pleural fluid to those in the blood, using Light's criteria.
• The traditional definitions of transudate as a pleural effusion due to systemic factors and an exudate as a pleural effusion due to local factors have been used since 1940 or earlier ( Light et al ., 1972 ).
• However, pleural fluid testing is not perfect, and the final decision about whether a fluid is a transudate or an exudate is based not on chemical analysis of the fluid, but on accurate diagnosis of the disease that produces the fluid.
• Previous to Light's landmark study, which was based on work by Chandrasekhar, investigators unsuccessfully attempted to use other criteria, such as specific gravity, pH, and protein content of the fluid, to differentiate between transudates and exudates.
• A transudate is defined as pleural fluid to serum total protein ratio of less than 0.5, pleural fluid to serum LDH ratio < 0.6, and absolute pleural fluid LDH < 200 IU or < 2 / 3 of the normal.
• The usual criterion ( included in Light's criteria ) is that a ratio of fluid LDH versus upper limit of normal serum LDH of more than 0.6 or } } indicates an exudate, while a ratio of less indicates a transudate.
• Measuring LDH in fluid aspirated from a pleural effusion ( or pericardial effusion ) can help in the distinction between exudates ( actively secreted fluid, e . g . due to inflammation ) or transudates ( passively secreted fluid, due to a high hydrostatic pressure or a low oncotic pressure ).