Brief Answer:
They are cells lining the surface of your urinary tract/genital tract.

Detailed Answer:
Hello,
Thanks for trusting Healthcaremagic!
I have gone through your query and I can understand your concerns.
Epithelial cells are nothing but cells lining your urinary tract and genital tract.
In healthy individuals, epithelial cells from the bladder and external urethra are normally present in the urine in small amounts. However, the amount of epithelial cells in the urine increases when someone has a urinary tract infection or some other cause of inflammation like urinary tract infection or pelvic inflammatory disease. Keep in mind that presence of epithelial cells does not always indicate disease conditions.
Wishing you good health
Thanks

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