Todayโs path rounds are on ๐๐ก๐ฒ๐ฅ๐จ๐ญ๐ก๐จ๐ซ๐๐ฑ!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ก๐ฒ๐ฅ๐จ๐ญ๐ก๐จ๐ซ๐๐ฑ is the accumulation of ๐๐ก๐ฒ๐ฅ๐ in the thorax. Chyle is the fancy name for lymph fluid!
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Technically any species can get this, however we most commonly see it in cats.
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
Most cases of chylothorax are considered ๐ข๐๐ข๐จ๐ฉ๐๐ญ๐ก๐ข๐, meaning we donโt know why they happened! However, it is associated with right-side heart failure, obstruction or rupture of lymphatic vessels, or some types of thoracic tumours. The most commonly thought-of cause, although it is actually rare, is rupture of the ๐ญ๐ก๐จ๐ซ๐๐๐ข๐ ๐๐ฎ๐๐ญ, the main lymphatic vessel the returns lymph fluid into the bloodstream.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Chylothorax fills the chest with large amounts of a milky fluid. Lungs do not like to be in a fluid! This can cause ๐๐ญ๐๐ฅ๐๐๐ญ๐๐ฌ๐ข๐ฌ, or compression of the lungs leading to improper inflation. These animals may present with respiratory distress.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
One of the main components of lymph fluid is ๐ญ๐ซ๐ข๐ ๐ฅ๐ฒ๐๐๐ซ๐ข๐๐๐ฌ, a component of fat. When an animal is suspected to have chylothorax, ๐ญ๐ก๐จ๐ซ๐๐๐จ๐๐๐ง๐ญ๐๐ฌ๐ข๐ฌ is performed, where a needle is introduced into the chest cavity to retrieve a sample of fluid. The triglyceride level on this fluid is measured, and if it is higher than the triglyceride content of the blood, the veterinarian can confirm the diagnosis of chylothorax. However, usually the veterinarian can get a pretty good idea that the fluid is chyle just from the characteristic milky appearance!
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
If known, the underlying cause should be treated. However, since most of these cases are idiopathic, there often isnโt a specific thing to target in a treatment protocol. These cases often undergo ๐ญ๐ก๐จ๐ซ๐๐๐ข๐ ๐๐ฎ๐๐ญ ๐ฅ๐ข๐ ๐๐ญ๐ข๐จ๐ง, to block off the leaking thoracic duct and encourage new lymphatic vessels to form. If surgery is not an option, repeated thoracocentesis can help remove fluid and make the animal more comfortable, however the prognosis is quite poor for medical treatment alone.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-5) Various examples of chylothorax! Got milk? 
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 2. Sixth Edition.
Photos 1-5 ยฉ Noahโs Arkive contributors King, Hanna, Dodd, Crowell, McGavin licensed under CC BY-SA 4.0.
