The intestinal and renal alkaline phosphatase test measures specific forms of the enzyme alkaline phosphatase (ALP) that come from your intestines and kidneys. Your doctor may order it when your total ALP level is elevated and the source needs to be identified. A small blood sample is drawn from a vein in your arm and analyzed in a laboratory, usually with no special preparation. Results help show whether your digestive system or kidneys may be causing unusual ALP levels and guide your doctor in deciding whether more testing is needed.
This blood test measures the specific forms of the alkaline phosphatase (ALP) enzyme that come from your intestines and kidneys, helping your doctor identify the source of unusual ALP levels.
{"Measures intestinal and renal alkaline phosphatase enzymes in blood","Helps evaluate kidney and intestinal health","Results are compared with total alkaline phosphatase for better diagnosis","Abnormal levels may indicate digestive or kidney issues","A simple blood test is all that is needed"}
Key facts at a glance
- LOINC
- 43709-5
- Short code
- ALP-INT+REN
- Synonyms
- ALP Intest+renal SerPl Ql
- Category
- chemistry
- Sample
- serum
- Container
- SST (serum separator tube) or red top tube
- Units
- not specified
- Ref low
- 0
- Ref high
- 100
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Electrophoresis or isoenzyme-specific enzymatic assay
- CPT
- 84080
- SNOMED
- 271510001
- Specimen volume
- 1-2 mL serum minimum
- Stability
- Room temperature: 7 days; Refrigerated (2-8°C): 7-14 days; Frozen (-20°C): several months
- Hemolysis max
- 50
- Lipemia max
- 300
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
What is this test?
The intestinal and renal alkaline phosphatase test measures specific forms of the enzyme alkaline phosphatase (ALP) that come from your intestines and kidneys. ALP is found throughout the body, but this test focuses on these two specific types (isoenzymes) to help doctors understand if your digestive system or kidneys may be the source of any ALP abnormalities detected in a standard ALP test.
Why is this test performed?
Your doctor may order this test when your total alkaline phosphatase level is elevated, and they need to determine the source. Since ALP can come from liver, bones, intestines, and kidneys, this test helps pinpoint whether the intestines or kidneys are contributing to the elevated results. This information is valuable for diagnosing conditions affecting these specific organs.
How is the test done?
A healthcare professional will draw a small blood sample from a vein in your arm. The sample is then sent to a laboratory where specialists analyze it to identify and measure the intestinal and renal forms of alkaline phosphatase. You do not need to fast for this test, though your doctor may instruct you to do so based on your specific situation.
What do the results mean?
Results are typically reported as present or absent, or as a quantitative value indicating the amount of these specific ALP isoenzymes. Your doctor will interpret these results alongside your total ALP levels and other test results to determine what they mean for your health. Elevated levels may indicate certain conditions, while normal levels help rule out intestinal or kidney-related causes of ALP elevation.
Reference range
Negative (Absent/Not detected)not specified
Fasting preferred (intestinal fraction may rise postprandially, especially in blood group O/B secretors)
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test helps differentiate between various sources of elevated alkaline phosphatase. Elevated intestinal alkaline phosphatase may occur in conditions affecting the intestines, such as inflammatory bowel disease, celiac disease, or after intestinal injuries. Elevated renal alkaline phosphatase may indicate kidney disease, kidney infection, or kidney damage. This information helps doctors make more accurate diagnoses and provide appropriate treatment.
Frequently asked questions
Is fasting required before this test?
Are there any risks from this test?
How long does it take to get results?
What can affect my test results?
Will I need additional tests?
Sources
- 1
- 2
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 10, 2026. · Read our editorial policy