Urinalysis can be simply explained as the analysis of urine, which helps to detect certain diseases. This test can provide valuable information regarding the health condition of the person. While urinalysis is mainly conducted to find out the diseases of the urinary system, it may also come up with some information that can point towards other medical conditions. So this test is also included as a part of routine health checkups. In most cases, both macroscopic and microscopic analysis of the urine is done. Macroscopic analysis records those properties that are visible to the naked eye, like the urine color, clarity, presence of clots, sediments and cloudiness.
Dipstick analysis can also be conducted to find out the presence of proteins, blood and nitrites in the urine as well as to figure out the pH and gravity. Microscopic analysis is the study of urine under the microscope. This helps to detect the presence of bacteria or other microorganisms in the urine. Presence of red blood cells, white blood cells and epithelial cells can also be detected through such tests. What does the presence of epithelial cells in urine indicate? Let us find out...
What are Epithelial Cells
Epithelial tissue is one of the major types of tissues in the human body. While the skin is mainly composed of epithelial tissues, most of the inner body cavities and organs are also lined by them. These tissues are made of epithelial cells, which are of different types. As far as urinary tract is concerned, three types of epithelial cells are mainly involved. They are squamous, transitional and renal tubular cells. As the urinary tract is lined with epithelial tissue, it is normal that some of these cells are sloughed into the urine.
These cells are detected in the urine during microscopic urinalysis. However, the exact quantity and type of the cells are identified during the microscopic study of the urine sediment, which is often done as the last step of urinalysis. The urine sample is transferred to a test tube, which is placed in a centrifuge. After spinning for a few minutes, the test tube will contain a top liquid part and some sediments at the bottom. The liquid part is removed and the sediments are examined under a microscope, to identify casts, epithelial cells, urine crystals and bacteria.
Epithelial Cells in Urinalysis
As mentioned earlier, it is normal to find a few epithelial cells in urine samples. This is because of the regular shedding of cells from the bladder and external urethra. Epithelial cells from the kidneys are normally not shed. However, an increased quantity of epithelial cells in urine could indicate some health problems. Presence of abnormal forms of epithelial cells could also be a problem.
As per microscopic analysis of the urine sediment, the epithelial cells in the urine are classified as per the type and quantity. The quantity is given as occasional, moderate, few or many. Identifying the specific type of epithelial cells in the sample helps to detect the underlying medical condition, if there is any. While squamous cells are found on the skin, in the vagina and outer parts of the urethra, transitional ones are located in the bladder, ureter and renal pelvis. Renal tubular cells are found in the nephrons of the kidney.
- As mentioned above, the presence of a few epithelial cells, especially the squamous and transitional ones are considered normal in both men and women.
- Large number of squamous cells in urine may be due to contamination of the sample (as these cells are found in the external urethra). This is mainly seen in females.
- Even those with bacterial vaginal infection may have large number of squamous epithelial cells in the urine. Such cells are found to have bacteria attached to their surface and are called clue cells.
- In case of older females, parabasal squamous epithelial cells (smallest and immature epithelial cells of the vagina) may be found in urine samples. This is mostly seen in post-menopausal women, who have low estrogen levels.
- Large number of transitional cells in the urine could be an indication of some health problem. One of the possible causes is bladder infection.
- Presence of transitional cells in urine is not common and is sometimes seen in elderly people. In some cases, transitional cell cancer of the renal pelvis is found to be a reason.
- Presence of renal tubular cells in urine is not normal and in large numbers, can be a sign of some serious kidney problem like nephrotic syndrome.
- The urine sample of people with lipiduria may have renal tubular cells filled with fat deposits. Such cells are called oval fat bodies.
In short, the most common causes for the presence of epithelial cells in urine are infections and inflammation. In some cases, the possibility of malignancy cannot be ruled out. However, your health care provider is the best person to interpret the results of urinalysis and diagnose the problem. Thus, determining the type and quantity of epithelial cells in the urine will help to diagnose the underlying condition. In short, epithelial cells in urinalysis can be a cause of concern. If your routine urine test comes up with any such result, contact your doctor at the earliest.
Disclaimer: This HealthHearty article is for informational purposes only and should not be used as a replacement for expert medical advice.