Epithelial cells in urine are often found on a urinalysis (UA) because the lining of the urinary tract naturally sheds cells that get washed out in urine. In many cases, this is a normal finding and has no clinical relevance when other urine results are normal.

The type of epithelial cells in urine can help indicate where the cells came from, which can clarify whether the sample was contaminated or if there may be a urinary problem. Squamous cells are commonly linked to contamination during collection, while transitional or tubular (columnar) cells may be more concerning when present in higher amounts.

Lab reports often describe epithelial cells in urine as “few,” “some,” or “many,” and the count is interpreted along with bacteria, mucus, leukocytes, and any abnormal cell shapes. Higher levels may be seen with urinary tract infections (UTIs), menopause-related changes, or kidney problems, especially when other urine markers are also abnormal.

Interpreting results

The presence of epithelial cells is usually reported as:

Few, when there are 3 epithelial cells or fewer 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.

In most cases, the presence of epithelial cells in urine is not clinically significant. However, this finding should be interpreted together with other urinalysis parameters, such as the presence of mucus, bacteria, and the shapes of the cells.

Types of epithelial cells

Epithelial cells can be classified categorized based on where they come from in the body. Examples include:

Squamous epithelial cells: These are the largest type of epithelial cells and are easily found in urine samples. They typically originate from the vagina or urethra and are usually present due to contamination of the urine specimen;
Transitional epithelial cells: These cells line the bladder and urinary tract. When present in high numbers, they may indicate a urinary tract infection (UTI). Usually when these are high, leukocytes in the urine will also be high;
Columnar epithelial cells: These cells line the renal tubules and may appear in the urine when there is kidney damage or dysfunction.

A standard urine test only indicates whether epithelial cells are present or absent, without specifying their type. However, identifying the specific type of epithelial cells in the urine can help detect potential abnormalities in the body and assist the clinician in choosing the appropriate treatment.

Common causes

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 during collection, which occurs more frequently in women. A healthcare provider can usually determine whether the sample was contaminated by examining other findings in the urine. Typically, a contaminated specimen shows more epithelial cells and bacteria but few or no leukocytes.

To prevent contamination, clean the genital area with a wet wipe or by washing with water. Gently pat the area dry before collecting your sample. Begin urinating into the toilet to flush out any bacteria from the urethra, then collect the midstream urine in the provided cup. Be sure to submit the specimen right away.

2. Urinary tract infection

In a urinary tract infection (UTI), the test may show some or many epithelial cells, microorganisms, and sometimes mucus. There may also be more white blood cells (leukocytes) in the urine than normal.

3. Menopause

Postmenopausal women with low estrogen levels may have a higher number of epithelial cells in their urine. This finding is not a sign of illness and does not cause symptoms.

Women with menopause symptoms should have their hormone levels checked and discuss hormone replacement therapy (HRT) with their healthcare provider if needed.

4. Kidney problems

When a urine sample contains many epithelial cells that are tubular or columnar in shape, it may suggest a problem with the kidneys, since these cells usually come from kidney tissue. If most of the epithelial cells are columnar, this can indicate a more serious kidney injury and a possible decrease in kidney function.

Other signs that may indicate kidney damage include the presence of urea and creatinine in the urine, as well as symptoms of kidney problems such as a frequent urge to urinate, leg swelling, body itching, or persistent fatigue.

Epithelial Cells in Urine: What It Means