Epithelial cells in the urine usually means that there was normal shedding of cells along the urinary tract, and these cells were eliminated in the urine. This is considered to be a normal finding and is typically not of clinical relevance.
Although some epithelial cells in the urine is normal, the quantity of epithelial cells reported in the test as well as any changes to the shape of the cells or their nuclei are analyzed carefully, as abnormalities can be a sign of a more serious finding.
Each lab usually has their own format and reference range for reporting results, however epithelial cells are usually not quantified with an exact number. Quantities are reported as "few", "some" or "many". This result is rarely diagnostic, and often reviewed with other urine parameters to confirm the presence of an abnormality.
The main causes of epithelial cells in urine are:
1. Specimen contamination
The most common cause of a higher number of epithelial cells in the urine is contamination when collecting. This occurrence is more common in women. The doctor can usually confirm whether the urine was contaminated by looking at the other urine factors. Usually, a contaminated specimen will have more epithelial cells and bacteria, but rarely leukocytes.
To avoid contaminating your specimen, be sure to wipe the genital area with a wet wipe or perform genital hygiene, being sure to pat the area dry. Urinate first into the toilet to get rid of any urethral bacteria, and then urinate into the collection cup. Be sure to submit the specimen immediately.
2. Urinary tract infection
With urinary tract infections, many epithelial cells are usually noted in the urine. Microorganisms will also be present, and in some cases, the urine will also have mucus strings. If a UTI is confirmed, the doctor may also evaluate the quantity of leukocytes in the urine.
Use our online UTI symptoms checker to assess your risk for a urinary infection.
Women who are in a post-menopausal phase with low estrogen levels may also have a higher count of epithelial cells in the urine. However, it does not mean that these women are at higher risk for illness nor does it cause symptoms. Women who suspect they may be menopausal are advised to have their hormonal levels checked and to start hormone replacement therapy as necessary. Read ore about the common symptoms of menopause if you suspect you may be entering this phase.
4. Kidney problems
When many epithelial cells with tubular or columnar shapes are noted in a urine specimen, it may be a sign of a kidney problem, as these types of cells are most commonly seen in the kidneys. When most the epithelial cells are columnar, this indicates a more severe kidney injury with a risk for decreased functioning.
In addition to these changes, which are noted in a urine R&M test, other changes that signal kidney damage include urea and creatinine in the urine. Complete our online kidney symptoms checker if you suspect you may have a kidney issue.
The presence of lack of epithelial cells is usually reported in the following way:
- Few, when there are 3 epithelial cells or less observed in a high power field
- Some, when there are between 4 and 10 epithelial cells observed in a high power field
- Many, when there are 10 epithelial cells or more observed in a high power field
Most times, epithelial cells in the urine are not of clinical relevance. However, it is important to interpret this finding alongside other urine parameters, like the presence of mucus, bacteria and the cell shapes.
Types of epithelial cells
Epithelial cells can be classified by where they come from. Examples include:
- Squamous epithelial cells: These are the largest types of epithelial cells and are easily found in the urine. These cells are usually found in the vagina, or in the male or female urethra, and usually appear as a result of urine contamination.
- Transitional epithelial cells: These are present in the bladder and can be a sign of a UTI if noted in high quantities. Usually when these are high, leukocytes in the urine will also be high.
- Columnar epithelial cells: These are seen along the renal tubules, and can appear in the urine when there are kidney problems.
Normal urine cells will only report the lack or presence of epithelial cells, without any additional information about the type of cell. However, knowing the type of cells present in the urine can help to identify whether there is an abnormality in the body, which can guide the doctor’s prescribed treatment.