uroinepiteelit

Uroepithelial cells, also known as urothelium or transitional epithelium, form the specialized lining of the urinary tract. This tissue is found in the renal pelvis, ureters, urinary bladder, and the proximal part of the urethra. Its unique structure allows for remarkable distension, a crucial adaptation for the bladder's ability to store urine and expand significantly. The urothelium is a stratified epithelium, meaning it consists of multiple layers of cells. The surface layer is typically composed of larger, dome-shaped cells called umbrella cells, which are thought to provide a protective barrier against the corrosive effects of urine. Beneath these are several layers of intermediate cells, and at the base, a layer of basal cells.

The primary function of uroepithelial cells is to act as a barrier, preventing water and solutes from leaking from the urinary tract into the surrounding tissues. They also play a role in regulating the composition of urine. The cells possess specialized proteins, such as uroplakins, which contribute to their impermeability and mechanical strength. Changes in the appearance or number of uroepithelial cells in urine samples can be indicative of various medical conditions. For example, an increased presence of these cells might suggest inflammation, infection, or the presence of urinary tract stones. Abnormal urothelial cells, particularly those with atypical morphology, can also be a sign of urothelial carcinoma, a type of cancer that originates in the lining of the urinary tract. Routine urinalysis often includes microscopic examination of urine sediment to assess the characteristics of the shed uroepithelial cells.