Short answer
A urinalysis checks urine appearance, dipstick chemistry, and sometimes microscopic findings. It can help evaluate urinary tract infection (UTI) clues, kidney disease, diabetes-related glucose or ketones, dehydration, pregnancy-related concerns, blood in urine, protein in urine, and sample contamination.
It is not one diagnosis. A urinalysis is a cluster of clues that depends on symptoms, collection quality, medicines, menstrual or genital contamination, recent exercise, hydration, pregnancy status, kidney function blood tests, and whether a urine culture, UACR, or repeat sample is needed.
What a urinalysis checks
A complete urinalysis may include three layers: a visual check, a chemical dipstick, and a microscopic exam. Not every report includes every layer. Some clinics use reflex rules, where microscopy or culture is added only if the dipstick or symptoms meet certain criteria.
| Part of test | Common items | Why it matters |
|---|---|---|
| Visual appearance | Color, clarity, sometimes odor. | Concentrated urine, blood, bilirubin, medicines, supplements, or contamination can change appearance. |
| Chemical dipstick | Specific gravity, pH, protein, blood, glucose, ketones, nitrites, leukocyte esterase, bilirubin, urobilinogen. | Fast screening for UTI clues, kidney or metabolic patterns, hydration, and unexpected substances. |
| Microscopy | Red blood cells, white blood cells, epithelial cells, bacteria, yeast, casts, crystals. | Helps confirm whether a dipstick flag fits infection, kidney inflammation, stones, contamination, or another pattern. |
Common urinalysis findings
| Finding | May suggest | Important caveat | Follow-up question |
|---|---|---|---|
| Leukocyte esterase | White blood cells in urine, often from urinary tract inflammation or infection. | Can be affected by contamination or non-UTI inflammation; symptoms matter. | Are there urinary symptoms, fever, flank pain, or a culture result? |
| Nitrites | Certain bacteria that can convert nitrate to nitrite, often a UTI clue. | A negative nitrite result does not rule out UTI because not all bacteria produce nitrite. | Should a urine culture be done before antibiotics or if symptoms persist? |
| Blood | UTI, kidney stones, menstruation contamination, recent exercise, kidney disease, urinary tract conditions, or prostate-related causes. | Dipstick blood should be interpreted with microscopy; persistent microscopic blood needs follow-up. | Was blood confirmed by red blood cells on microscopy, and should the sample be repeated? |
| Protein | Kidney stress, fever, exercise, dehydration, diabetes, high blood pressure, kidney disease, or transient proteinuria. | Dipstick protein is not the same as UACR; concentration can affect the result. | Is UACR or urine protein-to-creatinine ratio needed? |
| Glucose | High blood glucose, diabetes questions, pregnancy context, or some medicine effects. | Blood glucose and A1C usually matter more than urine glucose alone. | Does this match recent blood glucose, A1C, symptoms, or diabetes medicines? |
| Ketones | Fasting, low-carbohydrate diet, vomiting, illness, pregnancy, heavy exercise, or diabetes-related ketoacidosis risk. | High ketones with diabetes symptoms can be urgent; urine ketones lag behind blood ketones. | Are blood glucose, symptoms, hydration, and diabetes safety instructions being checked? |
| Specific gravity | Urine concentration and hydration context. | Concentrated urine can make trace protein or ketones more likely; dilute urine can reduce sensitivity. | Was the sample unusually concentrated or diluted? |
| Casts or crystals | Possible kidney, stone, dehydration, medicine, or sample-handling context. | Type and amount matter; some findings are nonspecific. | Does microscopy need kidney-function blood tests, UACR, imaging, or repeat testing? |
UTI clues and urine culture context
Leukocyte esterase, nitrites, white blood cells, bacteria, blood, and urinary symptoms can point toward a UTI. CDC notes that urine tests may be ordered when needed, but symptoms such as burning, urgency, frequency, lower abdominal pain, fever, or flank pain change how the result is interpreted.
A urine culture is different from a urinalysis. Culture tries to grow and identify bacteria and may include antibiotic susceptibility testing. It is especially useful when symptoms are severe, recurrent, complicated, pregnancy-related, catheter-related, or not improving as expected.
Kidney and metabolic clues
Protein, blood, casts, and abnormal specific gravity can raise kidney follow-up questions, but a routine dipstick is only a starting point. NIDDK emphasizes urine albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) as key tests for chronic kidney disease assessment.
Glucose and ketones can raise diabetes, fasting, illness, pregnancy, and medication questions. A urine glucose or ketone flag should usually be interpreted with blood glucose, A1C, symptoms, and diabetes safety instructions rather than treated as a standalone wellness score.
Sample quality and false alarms
- Collection technique: Clean-catch midstream collection reduces skin, genital, and vaginal contamination.
- Menstruation or bleeding: Menstrual blood, vaginal bleeding, or genital irritation can affect blood and cell findings.
- Epithelial cells: Many squamous epithelial cells can suggest contamination, especially when bacteria are also reported.
- Timing and storage: Delayed testing, old samples, or improper storage can change bacteria, cells, pH, and crystal interpretation.
- Exercise and dehydration: Recent hard exercise or concentrated urine can contribute to temporary blood, protein, ketones, or specific-gravity changes.
- Medicines and supplements: Some medicines, vitamins, and dyes can change urine color or interfere with dipstick interpretation.
When to follow up urgently
Ask for urgent medical guidance if abnormal urinalysis results come with fever, chills, flank or back pain, pregnancy with UTI symptoms, visible blood in urine, inability to keep fluids down, severe dehydration, confusion, severe weakness, new swelling, very high blood glucose, moderate or large ketones in diabetes, or a clinician or lab flags the result as urgent.
Blood in urine deserves special care. The American Urological Association defines microhematuria by red blood cells on microscopic evaluation of a properly collected urine specimen, not dipstick alone. If blood is attributed to a UTI, repeat urinalysis after treatment may be used to confirm it resolves.
Questions to ask
- Was this a clean-catch sample, and were there many squamous epithelial cells suggesting contamination?
- Do my symptoms fit UTI, kidney stone, kidney inflammation, dehydration, diabetes, pregnancy-related concerns, or another pattern?
- Was blood confirmed by microscopy, or was it only a dipstick blood flag?
- Should I have urine culture, UACR, urine protein-to-creatinine ratio, kidney function blood tests, pregnancy testing, STI testing, or imaging?
- Should the urinalysis be repeated after hydration, avoiding intense exercise, finishing UTI treatment, or using a better collection technique?