exudates

Exudates are fluids released from tissues or mucous membranes, typically in response to injury or inflammation. In medicine, an exudate is fluid that leaks from capillaries or wounds and is rich in proteins and inflammatory cells. In botany, exudates are substances such as resins, gums, and latex that are secreted by plants, often in response to damage.

In clinical contexts, exudates are distinguished from transudates by higher protein content and cellularity. Common types of exudate include serous (clear or pale-yellow), serosanguineous (pinkish), sanguineous (bloody), purulent (pus-containing), and fibrinous exudates, which have a high fibrin content. Pus is a form of purulent exudate dominated by leukocytes and microbes.

The formation of exudate results from inflammatory mediators that increase vascular permeability, allowing plasma proteins, leukocytes, and other components to escape into tissue or wound sites. The specific composition reflects the underlying process (infection, trauma, autoimmune inflammation) and can influence healing and risk of complications.

Assessment of exudate in wounds or body cavities includes volume, color, consistency, odor, and timing. Laboratory analysis may measure protein content, cell counts, microbiology, pH, and glucose to guide management and distinguish infection from other inflammatory states.

Plants produce exudates to seal wounds, deter herbivores, or communicate with other organisms. Such exudates include latex, resins, gums, and essential oils, and they may contain complex mixtures of terpenes, phenolics, and other compounds used commercially or medicinally.