Urinalysis
A fundamental diagnostic test to assess kidney function, hydration status, and detect infections or metabolic disorders
Table of contents
Basic data
Urinalysis is a basic yet powerful diagnostic tool that analyzes the physical, chemical, and microscopic properties of urine. It helps evaluate hydration, detect urinary tract infections (UTIs), assess kidney function, and uncover signs of metabolic disorders such as diabetes.
The test is fast, inexpensive, and often used in routine health screening or when symptoms like fatigue, frequent urination, or flank pain are present. It can detect early dysfunction before symptoms escalate.
Category: Lab urine panel
Level: Beginner
Usefulness: Medium
Level
Beginner
Usefulness
Medium
Detects urinary tract infections
Presence of nitrites, leukocytes, or bacteria suggests possible UTI — especially useful when symptoms are unclear.
Assesses kidney and metabolic health
Detects protein, glucose, or blood in urine, which can indicate kidney damage, diabetes, or hypertension-related issues.
Evaluates hydration and overall function
Urine color, specific gravity, and pH reflect hydration status and acid-base balance, helping to guide lifestyle or protocol adjustments.
How it works
Sample collection
A midstream clean-catch urine sample is collected into a sterile container — usually first morning urine is preferred for consistency.
Chemical and microscopic analysis
Dipstick tests measure various compounds (e.g. protein, glucose, pH), while microscopic analysis identifies cells, crystals, and microbes.
Measures
Specific gravity
Indicates urine concentration — used to assess hydration or kidney concentrating ability.
pH
Reflects urine acidity or alkalinity; may be influenced by diet, medications, or underlying conditions.
Protein
Presence suggests possible kidney damage or inflammation.
Glucose
Can indicate diabetes or impaired glucose regulation if persistently present.
Leukocytes and nitrites
Signs of bacterial infection and immune response in the urinary tract.
Microscopic elements
Includes red/white blood cells, casts, crystals — helpful in diagnosing kidney disease or stones.
Reliability
Repeatability
High repeatability when samples are fresh and properly collected. Dipstick readings are standardized but may vary slightly by lab.
Sensitivity to conditions
Results can be affected by dehydration, menstruation, physical activity, or sample contamination.
Limitations
May yield false positives or negatives
Color, medications, or improper collection can distort results. Retesting is often needed for confirmation.
Cannot diagnose conditions alone
Urinalysis suggests potential issues but does not confirm specific diseases without context.
Frequency
Suggested cadence
Recommended annually as part of preventive health screening, or more frequently in individuals with diabetes, hypertension, or kidney risk.
Cost
Typical costs
Urinalysis is inexpensive, typically $5–15 USD or 20–50 PLN in most labs. Often bundled with routine bloodwork.
Availability
Where available
Available in nearly all laboratories and clinics. No special equipment or preparation is needed.
Preparation
How to prepare
Avoid intense physical activity, vitamin C supplements, and certain medications before testing. First morning urine is preferred.
Interpretation
Normal result
Indicates good kidney function, hydration, and absence of infection or metabolic abnormalities.
Abnormal findings
Presence of blood, protein, glucose, or nitrites may indicate underlying pathology and require further evaluation.
Alternatives
24-hour urine collection
Measures total urine output and compound excretion over a full day — more precise but less convenient.
Blood urea nitrogen (BUN) and creatinine
Blood-based kidney function markers that often complement urinalysis to assess renal health.
FAQ
Can diet or supplements affect urinalysis?
Yes. Certain foods (beets, asparagus), supplements (vitamin C, B), and drugs can alter color or interfere with dipstick chemistry.
Should I be worried if protein or blood appears once?
Not necessarily — many factors can cause temporary abnormalities. Your doctor may recommend retesting or additional diagnostics.