intersticiális

Intersticiális, or interstitial, is a term used in anatomy and medicine to describe structures or spaces located between the functional units of a tissue or organ. The word derives from the Latin interstitium, meaning “between spaces.”

In anatomy, the interstitium refers to the network of connective tissue and the extracellular matrix that surrounds cells and vessels. It contains interstitial fluid, a filtrate of plasma that bathes cells and participates in nutrient exchange, waste removal, and signaling. The interstitium is distinct from the lumen of a hollow organ or the air spaces of the lungs and can vary in density and composition across tissues.

In clinical contexts, diseases described as interstitial affect the interstitium rather than the parenchymal spaces or ducts. Examples include interstitial lung disease, where inflammation or scarring expands the interstitial tissue of the lungs; interstitial nephritis in the kidneys; and edema, where fluid accumulates in the interstitial spaces. Changes in the interstitium can alter tissue stiffness, diffusion of gases and nutrients, and organ function. Imaging often highlights interstitial patterns, such as reticular or nodular markings on chest radiographs or computed tomography.

The term is used across medical specialties and languages, with variants such as intersticiális (Hungarian) and intersticial (in several Romance languages). Understanding the interstitium is important for describing pathology that affects the supportive tissue surrounding ducts, vessels, and parenchyma in many organs.