There are three different types of epithelial cells that line the urinary tract. This includes the cells lining the ureters, urinary bladder, and the urethra. These are transitional epithelial cells, renal tubular cells, and squamous epithelial cells. Transitional epithelial cells are those cells that consist of multiple layers of epithelial cells. These are usually found throughout the length of the urinary tract. Renal tubular cells are the other type of epithelial cells that may be present in urine. These cells have an elongated nucleus and they are generally columnar in shape. The presence of renal tubule cells in the urine is of diagnostic significance, as it points towards an underlying kidney disease. The last type of epithelial cells are squamous cells. These cells are the largest cells seen in urine specimens. These cells are flat, usually with an angular or irregular outline. They have a thin, small nucleus with a fine, granular cytoplasm. They may be present as single cells scattered around the specimen or may be seen as variably-sized clusters.
Squamous Cells and Urinalysis
The simple logic behind this is that the epithelium that actually lines the entire urinary tract is mostly columnar in nature. In contrast, the epithelial cells seen on the skin are squamous epithelial cells, that is, they are large and flat. Hence, the presence of columnar epithelial cells in the urine indicates the presence of a pathological condition associated with the kidneys or some other part of the urinary tract. However, if squamous cells are seen, then the urine is contaminated. This can occur in many cases. One of them is that the urine that was collected was not an early morning specimen, which is the ideal specimen that is recommended by most pathologists for collection.
How to Avoid Getting Squamous Epithelial Cells in Urine
As we have established, the presence of squamous cells in the test signifies nothing but contamination of the urine sample, it is important to know how to avoid landing with a contaminated urine sample that may hinder or confuse the pathologist from reaching a diagnosis. For this purpose, it is important to know how to collect urine correctly. To do so, always ensure that the sample you collect is midstream. This is because if there are any loose epithelial cells that are present lining the skin around the labia or the penis, then they will get washed away in the initial flow of urine. This is the reason why the midstream sample is always said to the best sample for urinalysis. So always place the container for collection of urine after the patient has started voiding and stop just before the patient stops voiding.
Hence, we can conclusively say that the presence of these cells in urine is not a very alarming symptom and so, people needn't be worried if they happen to find these cells in urine sample. The best way to avoid contaminating urine with such cells is by taking care while collecting urine and by ensuring that the urine sample is always midstream when collected.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.