Table of ContentsView AllTable of ContentsWhat It IsCausesSymptomsLow vs. HighTestingResultsTreatment
Table of ContentsView All
View All
Table of Contents
What It Is
Causes
Symptoms
Low vs. High
Testing
Results
Treatment
Low alkaline phosphatase (ALP) can be a sign of several different conditions, including thyroid disease, celiac disease, and malnutrition.
ALP is an enzyme found in the blood that helps break down proteins. It plays a role in numerous processes in the human body, and any abnormalities in blood concentrations—either high or low—may indicate a health problem.
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Common Blood Tests and What They Mean
What Is Alkaline Phosphatase?
Scientists have not yet identified the full range of biochemical reactions that ALP instigates, but the enzyme is known to contribute to the following processes:
ALP is present in all tissues of the body. However, its highest concentrations are found in the liver, bones, kidneys, and intestines as well as the bile ducts (which drain bile from the liver) andgallbladder(which stores bile).
Certain diseases or conditions can impair ALP synthesis and lead to a drop in blood concentration. By contrast, damage to organs such as the liver or kidneys can trigger an increase of ALP in the bloodstream.
What Causes Low Alkaline Phosphatase?
Low ALP is less common than high levels. Abnormally low values may be the result of:
Signs and Symptoms of Low Alkaline Phosphatase
When you have low alkaline phosphatase, you may experience a variety of symptoms depending on the underlying health condition that is causing your levels to be low.
For example, if you have aplastic anemia you may experience frequent bruising, nosebleeds, and shortness of breath during activities. If you have celiac disease, you may experience gastrointestinal symptoms such as diarrhea or constipation, bloating, gas, and abdominal pain. Other conditions will cause very different symptoms.
Low Alkaline Phosphatase vs. High Alkaline Phosphatase
It is more common to have high ALP levels than low ALP levels. High ALP levels can be a sign of many different conditions, including:
Alkaline Phosphatase Testing
The ALP test measures the amount of alkaline phosphatase in a sample of blood. Your healthcare provider may order an ALP test as a part of a routine checkup. They may also order the test to help diagnose a suspected disease. The ALP is often done alongside other tests because this test alone can’t be used to diagnose a condition.
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How to Prepare for the Test
You will be asked to fast for 10 to 12 hours before the test to ensure an accurate reading.Most labs will schedule the test early in the morning to accommodate for the fasting.
Many drugs can interfere with ALP test results. Advise your healthcare provider or the lab of any medications or supplements you are taking, including the following:
Your healthcare provider will tell you if you need to stop taking any medications or supplements before the test. Do not discontinue any medications unless your healthcare provider tells you to.
What Happens During the Test?
As with other blood tests, the healthcare provider will draw blood from a vein in your arm using a small needle. The blood will be placed in a vial and sent to a laboratory for analysis. The blood draw typically takes less than five minutes. You may feel a prick or sting when the needle is inserted.
Like other blood tests, there is very little risk in having an alkaline phosphatase level test. You may experience mild pain and bruising where the blood was drawn.
What Do the Results Mean?
Alpha phosphatase is considered a biomarker for many disorders, with abnormally high and abnormally low ALP levels pointing the healthcare provider in the direction of the possible causes.
The ALP test results are presented as a reference range of values measures in enzyme units per liter (U/L) or microkatals per liter (μkat/L). Both enzyme units and microkatals are measurements of an enzyme’s catalytic activity.
ALP values that fall outside these reference ranges are considered abnormal. On their own, abnormal ALP values are not diagnostic but can provide a clue as to the underlying cause.
If your ALP levels are low, your healthcare provider may also order blood tests to look forhormone imbalances(such as occurs in thyroid or parathyroid disease),generalized inflammation, or genetic mutations.
Based on the results of these blood tests, a healthcare provider can expand the investigation and order the appropriate tests and procedures to definitively diagnose the cause.
In adults, the normal range of alkaline phosphatase is 33 to 96 U/L. What is considered “normal” may vary from laboratory to laboratory.
Alkaline Phosphatase (ALP) Testing: What to Expect
How Low Alkaline Phosphatase Is Treated
The treatment for low ALP depends on the underlying cause.
Low Alkaline Phosphatase and CancerLow ALP has been associated with poor prognosis in people with certain types of tumors, including colorectal cancer (CRC), breast cancer, and non-small cell lung cancer (NSCLC).In these cases, low ALP activity may be associated with poorlydifferentiated cancer cells, which grow and spread more quickly.
Low Alkaline Phosphatase and Cancer
Low ALP has been associated with poor prognosis in people with certain types of tumors, including colorectal cancer (CRC), breast cancer, and non-small cell lung cancer (NSCLC).In these cases, low ALP activity may be associated with poorlydifferentiated cancer cells, which grow and spread more quickly.
Low ALP has been associated with poor prognosis in people with certain types of tumors, including colorectal cancer (CRC), breast cancer, and non-small cell lung cancer (NSCLC).
In these cases, low ALP activity may be associated with poorlydifferentiated cancer cells, which grow and spread more quickly.
What Does a Medical Pathologist Do?
Summary
Treatment for low alkaline phosphatase depends on the underlying cause.
9 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sharma U, Pal D, Prasad R.Alkaline phosphatase: An overview.Indian J Clin Biochem. 2014;29(3):269-78. doi:10.1007/s12291-013-0408-ySchmidt T, Schmidt C, Amling M, Kramer J, Barvencik F.Prevalence of low alkaline phosphatase activity in laboratory assessment: Is hypophosphatasia an underdiagnosed disease?Orphanet J Rare Dis. 2021;16(1):452. Published 2021 Oct 28. doi:10.1186/s13023-021-02084-wUpToDate.Causes of an elevated alkaline phosphatase.MedlinePlus.Alkaline phosphatase.American Association for Clinical Chemistry.Alkaline phosphase (ALP).Primary Care Notebook.Drug-induced alkaline phosphatase (raised).Hansen YBL.Recommendations on measurement units - why and how.EJIFCC. 2019;30(3):250-275.Mutua DN, Nyaga E, Njagi M, Orinda G.Liver function tests in normal pregnant women.J Liver.2018;7:2. doi:10.4172/2167-0889.1000228Jiang T, Zeng Q, He J.Do alkaline phosphatases have great potential in the diagnosis, prognosis, and treatment of tumors?Transl Cancer Res. 2023;12(10):2932-2945. doi:10.21037/tcr-23-1190
9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sharma U, Pal D, Prasad R.Alkaline phosphatase: An overview.Indian J Clin Biochem. 2014;29(3):269-78. doi:10.1007/s12291-013-0408-ySchmidt T, Schmidt C, Amling M, Kramer J, Barvencik F.Prevalence of low alkaline phosphatase activity in laboratory assessment: Is hypophosphatasia an underdiagnosed disease?Orphanet J Rare Dis. 2021;16(1):452. Published 2021 Oct 28. doi:10.1186/s13023-021-02084-wUpToDate.Causes of an elevated alkaline phosphatase.MedlinePlus.Alkaline phosphatase.American Association for Clinical Chemistry.Alkaline phosphase (ALP).Primary Care Notebook.Drug-induced alkaline phosphatase (raised).Hansen YBL.Recommendations on measurement units - why and how.EJIFCC. 2019;30(3):250-275.Mutua DN, Nyaga E, Njagi M, Orinda G.Liver function tests in normal pregnant women.J Liver.2018;7:2. doi:10.4172/2167-0889.1000228Jiang T, Zeng Q, He J.Do alkaline phosphatases have great potential in the diagnosis, prognosis, and treatment of tumors?Transl Cancer Res. 2023;12(10):2932-2945. doi:10.21037/tcr-23-1190
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Sharma U, Pal D, Prasad R.Alkaline phosphatase: An overview.Indian J Clin Biochem. 2014;29(3):269-78. doi:10.1007/s12291-013-0408-ySchmidt T, Schmidt C, Amling M, Kramer J, Barvencik F.Prevalence of low alkaline phosphatase activity in laboratory assessment: Is hypophosphatasia an underdiagnosed disease?Orphanet J Rare Dis. 2021;16(1):452. Published 2021 Oct 28. doi:10.1186/s13023-021-02084-wUpToDate.Causes of an elevated alkaline phosphatase.MedlinePlus.Alkaline phosphatase.American Association for Clinical Chemistry.Alkaline phosphase (ALP).Primary Care Notebook.Drug-induced alkaline phosphatase (raised).Hansen YBL.Recommendations on measurement units - why and how.EJIFCC. 2019;30(3):250-275.Mutua DN, Nyaga E, Njagi M, Orinda G.Liver function tests in normal pregnant women.J Liver.2018;7:2. doi:10.4172/2167-0889.1000228Jiang T, Zeng Q, He J.Do alkaline phosphatases have great potential in the diagnosis, prognosis, and treatment of tumors?Transl Cancer Res. 2023;12(10):2932-2945. doi:10.21037/tcr-23-1190
Sharma U, Pal D, Prasad R.Alkaline phosphatase: An overview.Indian J Clin Biochem. 2014;29(3):269-78. doi:10.1007/s12291-013-0408-y
Schmidt T, Schmidt C, Amling M, Kramer J, Barvencik F.Prevalence of low alkaline phosphatase activity in laboratory assessment: Is hypophosphatasia an underdiagnosed disease?Orphanet J Rare Dis. 2021;16(1):452. Published 2021 Oct 28. doi:10.1186/s13023-021-02084-w
UpToDate.Causes of an elevated alkaline phosphatase.
MedlinePlus.Alkaline phosphatase.
American Association for Clinical Chemistry.Alkaline phosphase (ALP).
Primary Care Notebook.Drug-induced alkaline phosphatase (raised).
Hansen YBL.Recommendations on measurement units - why and how.EJIFCC. 2019;30(3):250-275.
Mutua DN, Nyaga E, Njagi M, Orinda G.Liver function tests in normal pregnant women.J Liver.2018;7:2. doi:10.4172/2167-0889.1000228
Jiang T, Zeng Q, He J.Do alkaline phosphatases have great potential in the diagnosis, prognosis, and treatment of tumors?Transl Cancer Res. 2023;12(10):2932-2945. doi:10.21037/tcr-23-1190
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