Exudates refer to any fluid exuded out of the tissues. The main causes of exudate production are inflammation and tissue injuries. There are different types of exudate produced by the body in response to the mentioned conditions. And the type of exudate can indicate what occurs. For instance, a serous exudate is the type of exudate that is clear, thin, and watery in contrast to a purulent exudate that is opaque, thick, and viscous. In tissue repair with an inflammatory phase, the exudate is typically serous. But when infection ensues, the exudate becomes purulent.
A serous exudate is comprised largely of a watery fluid of electrolytes and sugars. It may also contain proteins, white blood cells, and certain microorganisms but these components are relatively few. At times, the serous exudate simply leaks through the swollen skin as a result of an illness.
Word origin: serous + exudate, from exude meaning to ooze," which came from the Latin exsūdāre (to sweat out, i.e. ex- meaning out and sūdāre meaning to sweat)