# Bilirubin & Urobilinogen in Urine: What BIL and URO Mean on a Urine Test Strip **By Dr Pramod kumar** · 2026-10-07 ## What Do BIL and URO Mean on a Urine Test Strip? On a multi-parameter urine reagent strip: - **BIL** = Bilirubin - **URO** = Urobilinogen These two urine chemistry parameters are related to the body's processing of bilirubin, but they are not the same test and should not be interpreted interchangeably. Bilirubin and urobilinogen are commonly included in broader multi-parameter urinalysis strips such as [**Microsidd URS10T**](https://microsidd.com/products/microsidd-urs10t-complete-urinalysis-10-parameter-urine-test-strips) and [**Mission 10U**](https://microsidd.com/products/mission-urine-strips-10u). For a broader introduction to all common urinalysis parameters, read our [**10 Urine Test Strip Parameters Explained**](https://microsidd.com/blogs/knowledge-hub/10-urine-test-strip-parameters-explained). ## What Is Bilirubin? **Bilirubin** is a pigment formed during the normal breakdown of heme-containing proteins, particularly hemoglobin from aging red blood cells. It is processed by the liver and ultimately becomes part of bile. Under usual conditions, conjugated bilirubin is present only in very small amounts in urine. A urine bilirubin reagent strip is designed to screen for bilirubin that may be present in the urine specimen. ## What Does BIL Mean? **BIL** is the common abbreviation for **bilirubin** on urine reagent strips. The BIL reagent pad undergoes a colour reaction according to the chemistry of the specific product. The developed colour is compared with the bilirubin scale on the product-specific reference chart at the reading time stated by the manufacturer. ## What Does Bilirubin in Urine Mean? A positive urine bilirubin result means the reagent system has detected a bilirubin-related reaction in the specimen. This finding may require further evaluation, but it does **not** by itself diagnose liver disease, bile duct disease or another specific condition. Interpretation may need to consider: - Symptoms - Medical history - Other urine parameters - Blood bilirubin - Liver enzymes - Other liver or biliary investigations ## Can Bilirubin in Urine Diagnose Liver Disease? **No.** A positive BIL pad provides screening information only. It cannot independently determine: - The underlying cause - The severity of a liver problem - Whether bile flow is obstructed - Whether another condition is responsible Abnormal results should therefore be interpreted together with clinical and laboratory findings. ## Why Is Conjugated Bilirubin Relevant to Urine? Conjugated bilirubin is water-soluble and can appear in urine under certain circumstances. Unconjugated bilirubin is not normally filtered into urine in the same way because it is not freely water-soluble. This distinction helps explain why urine bilirubin testing provides different information from total blood bilirubin testing. ## What Is Urobilinogen? **Urobilinogen** is formed in the intestine during the metabolism of bilirubin. Some urobilinogen is reabsorbed and can subsequently appear in urine. Small amounts may therefore be present under normal circumstances. ## What Does URO Mean? **URO** is the common abbreviation for **urobilinogen** on urine reagent strips. The URO reagent area is designed to provide screening information about urobilinogen present in the urine specimen. The result should be interpreted using the colour chart and timing supplied for the exact reagent strip. ## What Does High Urobilinogen in Urine Mean? An increased URO result can occur for different reasons. Possible explanations may involve changes in: - Red blood cell breakdown - Bilirubin metabolism - Liver processing - Enterohepatic circulation A urine reagent strip cannot identify the exact cause. Further laboratory or clinical assessment may be required when the result is unexpected or persistent. ## What Does Low or Absent Urobilinogen Mean? Low or absent urobilinogen may also occur for different reasons. Its significance depends on the overall clinical situation and other laboratory findings. A single URO result should not be interpreted independently as evidence of a specific liver or biliary disorder. ## Bilirubin vs Urobilinogen in Urine Bilirubin – BIL Urobilinogen – URO Screens for bilirubin in urine Screens for urobilinogen in urine Related to water-soluble conjugated bilirubin Formed during intestinal bilirubin metabolism Not usually expected in significant amounts in normal urine Small amounts may normally be present Positive result may require liver/biliary assessment Abnormal result may require broader metabolic or liver assessment Does not independently diagnose liver disease Does not independently diagnose liver disease ## How BIL and URO Relate to Bilirubin Metabolism A simplified pathway is: 1. Old red blood cells are broken down. 2. Bilirubin is formed. 3. The liver processes and conjugates bilirubin. 4. Bilirubin enters bile and reaches the intestine. 5. Intestinal metabolism produces urobilinogen. 6. Some urobilinogen is reabsorbed and may appear in urine. This is why BIL and URO can provide complementary information, although neither is diagnostic by itself. ## Can BIL and URO Be Interpreted Together? Yes, they can be considered together as part of broader urine chemistry screening. However, combinations of BIL and URO results should not be treated as a standalone diagnostic algorithm. Interpretation may also require: - Blood bilirubin - ALT and AST - ALP and GGT - Complete blood count - Other liver-function tests - Clinical history - Imaging where appropriate ## Can a Negative BIL Result Rule Out Liver Disease? No. A negative urine bilirubin result does not exclude liver or biliary disease. Urine bilirubin is only one screening parameter and may be influenced by the type and stage of the underlying process. ## Can a Normal URO Result Rule Out Liver Disease? No. A normal urobilinogen result does not rule out all liver, biliary or hematological abnormalities. Urinalysis findings should always be interpreted in context. ## How to Test BIL and URO Using a Urine Strip The exact procedure depends on the reagent-strip product, so always follow the Instructions for Use supplied with the exact strips. A general workflow is: 1. Collect a fresh urine specimen in a clean, suitable container. 2. Check the strip expiry date and condition. 3. Remove one strip without touching the reagent pads. 4. Close the strip container immediately. 5. Immerse the required reagent areas according to the IFU. 6. Remove the strip after the specified immersion period. 7. Remove excess urine as directed. 8. Start timing immediately. 9. Compare BIL and URO with their respective colour scales at the specified reading times. 10. Record the results where required. 11. Dispose of the used strip appropriately. For detailed strip-reading technique, read: [**How to Read Urine Test Strips Correctly: Colour Chart, Timing & Common Errors →**](https://microsidd.com/blogs/knowledge-hub/how-to-read-urine-test-strips-colour-chart-timing) ## Why a Fresh Urine Specimen Matters Bilirubin and urobilinogen results can be affected by specimen handling and environmental exposure. Fresh urine is generally preferred for routine reagent-strip testing unless the product instructions specify otherwise. Use a clean, suitable specimen container. [**View Urine Specimen Container →**](https://microsidd.com/products/urine-container-sterile-50ml) ## Why Light Exposure Matters for Bilirubin Bilirubin can degrade with prolonged exposure to light. This means a urine specimen that has been left exposed to strong light for an extended period may produce a misleading bilirubin result. Follow the specimen-handling recommendations provided by the laboratory or manufacturer. ## Why Timing Matters for BIL and URO The bilirubin and urobilinogen reagent pads may have different development times. Reading the pad too early may result in an incomplete reaction, while reading too late may produce colour changes outside the intended interpretation window. **Use the exact reading times stated on the product chart.** ## Use Only the Correct Colour Chart Urine reagent-strip colour charts are product-specific. Do not use: - A chart from another brand - A chart from another strip configuration - A generic online colour chart - A damaged or faded reference chart Always compare the BIL and URO pads with the correct scales supplied with the exact strip. ## What Can Affect a Bilirubin Strip Result? Potential influences vary by manufacturer but may include: - Old specimens - Light exposure - Incorrect strip storage - Expired strips - Incorrect reading time - Some medications or pigments - Product-specific chemical interferences Always check the exact product IFU for known limitations. ## What Can Affect a Urobilinogen Result? Possible influences can include: - Specimen age - Storage conditions - Light exposure - Incorrect reading time - Some medications - Chemical interference - Product-specific reagent limitations ## Which Urine Strips Test BIL and URO? BIL and URO are usually found on broader multi-parameter urine test strips rather than focused glucose + protein or glucose + ketone strips. ### Microsidd URS10T [**Microsidd URS10T**](https://microsidd.com/products/microsidd-urs10t-complete-urinalysis-10-parameter-urine-test-strips) includes: - Leukocytes - Nitrite - **Urobilinogen** - Protein - pH - Blood - Specific Gravity - Ketones - **Bilirubin** - Glucose [**View Microsidd URS10T 10-Parameter Urine Test Strips →**](https://microsidd.com/products/microsidd-urs10t-complete-urinalysis-10-parameter-urine-test-strips) ### Mission 10U Microsidd also supplies [**Mission 10U Urinalysis Reagent Strips**](https://microsidd.com/products/mission-urine-strips-10u) for broader multi-parameter urine chemistry screening. [**View Mission 10U →**](https://microsidd.com/products/mission-urine-strips-10u) ## Why Focused 2-Parameter Strips Do Not Include BIL and URO Focused strips such as glucose + protein or glucose + ketone are designed for specific urine chemistry requirements. They generally do not include bilirubin and urobilinogen. If BIL and URO are required, a broader multi-parameter urinalysis strip such as URS10T or Mission 10U is more appropriate. ## BIL and URO Within a Broader Urinalysis Bilirubin and urobilinogen should be interpreted alongside other urine chemistry parameters where relevant. A broader strip may also provide: - Glucose - Protein - Ketones - Leukocytes - Nitrite - Blood - pH - Specific Gravity This broader profile can provide more context than an isolated parameter alone. ## Visual Reading vs Analyzer Reading Many multi-parameter urine reagent strips are designed for visual colour-chart interpretation. Professional laboratories may use compatible urine chemistry analyzers for supported reagent-strip systems. Visual Reading Analyzer Reading Operator compares reagent colours Analyzer measures reagent-pad reflectance Useful for lower-volume workflows Useful for repeated laboratory testing Manual recording May support result storage and printing Lighting and perception can affect colour interpretation Helps standardize compatible strip reading Professional analyzer options available through Microsidd include: [**Mission U120 Urine Analyzer →**](https://microsidd.com/products/urine-analyzer-u120) [**Mission U500 Urine Analyzer →**](https://microsidd.com/products/mission%C2%AE-u500-urine-analyzer) Always verify exact reagent-strip compatibility before analyzer use. ## When Should Abnormal BIL or URO Results Be Followed Up? Further assessment may be appropriate when: - Bilirubin remains positive on repeat testing - Urobilinogen is repeatedly outside the expected range - Symptoms are present - Other liver-related tests are abnormal - Multiple urinalysis parameters are abnormal together - A healthcare professional recommends additional testing The appropriate next step depends on the complete clinical situation. ## Explore the Microsidd Urine Chemistry Range Microsidd's Urine Chemistry collection includes focused urine reagent strips, 10-parameter urinalysis strips, urine analyzers, specimen containers and analyzer accessories. [**Explore the Complete Urine Chemistry Collection →**](https://microsidd.com/collections/urine-chemistry) ## Continue Learning About Urinalysis - [**Urinalysis & Urine Test Strips Complete Guide**](https://microsidd.com/blogs/knowledge-hub/urinalysis-urine-test-strips-complete-guide) - [**10 Urine Test Strip Parameters Explained**](https://microsidd.com/blogs/knowledge-hub/10-urine-test-strip-parameters-explained) - [**How to Read Urine Test Strips Correctly**](https://microsidd.com/blogs/knowledge-hub/how-to-read-urine-test-strips-colour-chart-timing) - [**Leukocytes & Nitrite in Urine**](https://microsidd.com/blogs/knowledge-hub/leukocytes-nitrite-in-urine-uti-screening) - [**Blood, pH & Specific Gravity in Urine**](https://microsidd.com/blogs/knowledge-hub/blood-ph-specific-gravity-in-urine-blo-ph-sg) - [**Urine Glucose Test Strips Complete Guide**](https://microsidd.com/blogs/knowledge-hub/urine-glucose-test-strips-complete-guide) - [**Protein in Urine Test Strips Complete Guide**](https://microsidd.com/blogs/knowledge-hub/protein-in-urine-test-strips-complete-guide) - [**Ketones in Urine Test Strips Complete Guide**](https://microsidd.com/blogs/knowledge-hub/ketones-in-urine-test-strips-complete-guide) ## Frequently Asked Questions ### What does BIL mean on a urine test strip? BIL stands for bilirubin. ### What does URO mean? URO stands for urobilinogen. ### Is bilirubin normally present in urine? Significant bilirubin is not generally expected in normal urine. A positive result may require further assessment. ### Is urobilinogen normally present in urine? Small amounts of urobilinogen may normally be present. ### Does bilirubin in urine mean liver disease? Not necessarily. A positive result is a screening finding and does not identify the exact cause. ### Can a negative BIL result rule out liver disease? No. A negative urine bilirubin result does not rule out all liver or biliary disorders. ### Does high urobilinogen mean liver disease? Not automatically. Urobilinogen can change for several reasons and should be interpreted together with other tests. ### Are BIL and URO the same test? No. They are related through bilirubin metabolism but measure different urine chemistry parameters. ### Can light affect bilirubin in urine? Yes. Prolonged light exposure can degrade bilirubin and potentially affect the result. ### Which Microsidd strip includes BIL and URO? [**Microsidd URS10T**](https://microsidd.com/products/microsidd-urs10t-complete-urinalysis-10-parameter-urine-test-strips) includes both bilirubin and urobilinogen. ### Does Mission 10U include BIL and URO? Yes. [**Mission 10U**](https://microsidd.com/products/mission-urine-strips-10u) includes both parameters as part of its multi-parameter urinalysis profile. ### Can GLU + PRO or GLU + KET strips test bilirubin? No. Focused 2-parameter strips do not provide BIL and URO testing. ### Can I use a colour chart from another brand? No. Always use the chart supplied with the exact reagent-strip product. ### Can urine strips be reused? No. Urine reagent strips are intended for single use only. ### What specimen container should I use? Use a clean, suitable urine specimen container appropriate for the intended test. [**View Urine Specimen Container →**](https://microsidd.com/products/urine-container-sterile-50ml) ## Medical Information Notice This article is provided for general educational and product-selection information and is not a substitute for medical advice, diagnosis or treatment. Bilirubin and urobilinogen urine reagent-strip results are screening findings. Abnormal results do not by themselves diagnose liver disease, biliary disease, hemolytic disorders or another specific medical condition. Results may be influenced by specimen age, light exposure, storage conditions, medications, testing technique and other physiological or clinical factors. Unexpected, persistent or clinically significant abnormalities should be evaluated by an appropriately qualified healthcare professional and confirmed with additional laboratory or clinical investigations where necessary. Do not begin, stop or modify medication or other medical treatment solely on the basis of a urine reagent-strip result. Always follow the Instructions for Use supplied with the exact urine reagent strip being used. --- > Source: [Microsidd India](https://microsidd.com/blogs/knowledge-hub/bilirubin-urobilinogen-in-urine-bil-uro)