Urobilinogen is a byproduct of bilirubin that is eventually eliminated through the stool and urine. Although urobilinogen is normally found in the urine, higher or lower levels may be a sign of a liver problem. Read on to find out what urobilinogen is, how it can be tested, and what its levels may reveal about your health.
What is Urobilinogen?
Urobilinogen is a colorless pigment produced from the breakdown of bilirubin by gut bacteria. The majority of this compound is excreted in feces, and a small amount is reabsorbed and excreted in the urine [1].
When bilirubin production increases because of red blood cell destruction (hemolysis) or liver disease, urobilinogen levels rise in the urine. On the other hand, when insufficient bilirubin reaches the gut due to decreased bile flow, urobilinogen production is reduced, resulting in extremely low or absent urinary urobilinogen levels. For these reasons, a urobilinogen test is used with other tests to help detect liver, gallbladder, or red blood cell problems [1, 2].
Urobilinogen Tests
Urobilinogen is most commonly measured in the urine. This is usually done as part of a urinalysis test, which measures many other substances in your urine, including proteins, ketones, and glucose. A urinalysis is often part of a routine health exam to screen for early signs of disease [3].
Your doctor may also order this test to monitor existing liver conditions, or if you have symptoms of liver disease. These include [4, 5, 6]:
- yellowing of the skin and eyes (jaundice)
- dark-colored urine
- nausea and vomiting
- itchy skin
- pain and swelling in the abdomen
- chills
- fever
- loss of appetite
- weakness/fatigue
- disorientation or confusion
Urobilinogen levels can also be measured in the stool (although this is not done as often).
Normal Levels
Urobilinogen is normally found in trace amounts in the urine (0.2 – 1.0 mg/dL) [7].
Urobilinogen levels < 0.2 mg/dL are considered low.
Urobilinogen levels > 1.0 mg/dL are considered high [8].
However, these values vary from lab to lab.
Limitations
One study found that although the urine urobilinogen test was a good screen for elevated blood bilirubin levels, it was not as useful for detecting liver problems due to a high proportion of false-negative results [9].
The urobilinogen test, by itself, is not enough to diagnose any condition. Talk to your doctor about what your test results mean and how to manage any underlying health conditions [10].
Low Urobilinogen Levels
Symptoms
Symptoms of low urobilinogen levels depend on the underlying cause. If you have reduced bile flow, you may experience [11, 12]:
- Itchy skin
- Fatigue
- Yellow complexion (jaundice)
- Dark urine
- Lightly colored or foul-smelling stool
- Anorexia
- Nausea
- Vomiting
- Weight loss
Causes
1) Reduced Bile Flow
Cholestasis, or reduced bile flow from the liver to the intestines, can cause bilirubin to build up in the bloodstream instead of being eliminated normally. This can reduce the production of urobilinogen, which leads to lower levels in the urine [1, 13].
Urinary urobilinogen levels were significantly lower in infants with biliary atresia (narrow, blocked, or absent bile ducts) compared to healthy infants in an observational study of 75 infants [13].
Causes of cholestasis include [12]:
- Bile duct blockage (gallstones, cysts, and tumors)
- Liver disease/damage
- Pregnancy
- Severe infection
- Pancreatic cancer
Generally, if you have symptoms of liver disease and bilirubin in your urine but an absence of or low urobilinogen, this suggests that not enough bile is flowing to your gut [1, 5].
2) Certain Medications
Broad-spectrum antibiotics destroy gut bacteria, which can prevent the production of urobilinogen [1].
In a study of 18 healthy people, antibiotic treatment for 6 days reduced urobilinogen levels in the stool [14].
False Negative Results
Some factors can interfere with your lab tests and cause false negative results. These include [1, 3, 15, 8]:
- Exposure of urine sample to direct sunlight – urobilinogen breaks down when exposed to sunlight
- Substances that acidify urine (e.g. vitamin C)
Ways to Increase Urobilinogen
1) Treat Underlying Conditions
Address any underlying conditions that are causing low urobilinogen levels.
If you have cholestasis (reduced bile flow), promote the health of your liver by:
- Eating a well-balanced diet [16]
- Drinking moderate to high (> 2-3 cups) amounts of coffee (regardless of caffeine content) on a regular basis [17, 18]
- Getting more quality sleep [19]
- Eating more foods that can help detoxify the liver and kidneys such as asparagus, cabbage, and broccoli [20]
- Drinking more water [20]
- Buying organic meats and vegetables whenever possible to avoid chemical additives and pesticides that damage the liver [21]
- Going to the sauna – saunas are beneficial for decreasing toxins in the body [22]
- Limiting your alcohol intake – excess alcohol can damage liver cells and worsen existing liver conditions [23]
- Reviewing your medications – some drugs or supplements can damage the liver. Have a doctor or pharmacist review your medications to see if any could be harmful to the liver [24, 5]
2) Review Your Medications
If you are taking antibiotics, discuss lowering your dose or alternative options with your doctor.
High Urobilinogen Levels
Symptoms
Symptoms of high urobilinogen levels in your urine depend on the underlying cause. If you have a liver or gallbladder disease, you may experience [4, 5, 6]:
- yellowing of the skin and eyes (jaundice)
- dark-colored urine
- nausea and vomiting
- chills
- fever
- loss of appetite
- weakness/fatigue
- disorientation or confusion
If you have hemolysis (red blood destruction), you may have [25]:
- dark urine
- back pain
- yellow skin (jaundice)
- rapid heart rate (tachycardia)
- anemia
Causes
1) Liver Disease or Damage
Liver damage and disease (e.g., viral hepatitis and liver cirrhosis) can increase bilirubin levels, resulting in higher urobilinogen levels in the urine [1].
Urobilinogen levels also correlate with blood levels of liver enzymes (e.g. ALT, AST), which rise in response to liver damage [26].
2) Excessive Red Blood Cell Breakdown
Conditions that increase the destruction of red blood cells (e.g. hemolytic anemia, pernicious anemia, intravascular hemolysis, congestive heart failure) raise bilirubin levels, which increases the production of urobilinogen in the gut [1, 27, 3].
Usually, if you have excess red blood cell destruction (hemolysis), you will have urobilinogen in your urine but undetectable amounts of bilirubin [1, 28].
3) Malaria
Urobilinogen levels were higher in 365 malaria patients [29].
Another study of 620 people with malaria found that the presence of urobilinogen in the urine was associated with an increased risk of severe malaria with the following complications [30]:
- Thrombocytopenia (low platelet count)
- Neurological dysfunction
- Liver dysfunction
False Positive Results
Factors that can lead to false-positive results include [8]:
- Elevated nitrate levels in the urine
- High carbohydrate intake
- Timing (test is done later in the afternoon)
- Drugs that make the urine red, such as phenazopyridine (Pyridium)
Ways to Decrease Urobilinogen
1) Treat Underlying Conditions
Address any underlying conditions that are causing low urobilinogen levels. Talk to your doctor about why you may have low urobilinogen and what appropriate therapies are available.
2) Limit Your Alcohol Intake
Drinking too much alcohol can damage liver cells and worsen existing liver conditions [23].
Alcohol also decreases red blood cells, which may exacerbate anemia. One observational study of 17.7k people found that red blood cell count was reduced by alcohol consumption, with even the lowest intake showing a significant decrease in red blood cells [31].
3) Review Your Medications
Some drugs or supplements can damage the liver [5, 24]:
- Paracetamol (Tylenol)
- Aspirin
- Non-steroidal anti-inflammatory drugs
- Methyldopa
- Amiodarone
- Monoamine oxidase inhibitors
- Phenothiazines (such as chlorpromazine)
- Sodium valproate
- Oral contraceptives and hormone replacement therapy
- Chaparral leaf
- Ephedra
- Gentian
- Germander
- Kava
- Senna
- Vitamin A
- EGCG [32]
Have a doctor or pharmacist review your medications to see if any could be harmful to the liver.
4) Improve Sleep Quality
Good sleep is essential for liver health. Short sleep duration and poor sleep quality significantly increased the incidence of non-alcoholic fatty liver disease (NAFLD) in an observational study of 69k people [19].
5) Drink More Coffee
Drinking moderate to high amounts of coffee (regardless of caffeine content) on a regular basis may benefit liver health. In an observational study of 28k people, drinking more than 3 cups of coffee per day was associated with lower levels of liver enzymes (e.g. ALT, AST, ALP, and GGT) [17].
6) Exercise
If you have anemia resulting from red blood destruction exercise may help. Moderate physical activity signals the body to produce more red blood cells to increase the oxygen supply to your muscles [33].
However, avoid more intense and strenuous forms of exercise, as these can damage and destroy red blood cells. This is one of the reasons endurance athletes often have anemia [34].
