ALP test – Alkaline Phosphate

What is an ALP test?

ALP stands for alkaline phosphate level – an enzyme that is associated with the functioning of the liver and gallbladder and also the state of bones. It is a blood test that is often performed along with other blood tests that are prescribed to assess the functioning of the liver.

The main function of the ALP enzyme is the breakdown of proteins. It is mostly produced by the liver but can also be found in the gallbladder, intestines, pancreas, and kidneys. In pregnant women, some amount of ALP enzyme is also produced in the placenta.

Why has my doctor asked me to undergo an ALP test?

If you have been asked to get your ALP levels checked, then you might be showing symptoms of either liver/gallbladder diseases or that of any bone disorder.  The following are the common symptoms shown by an individual with abnormal ALP levels:

– Jaundice
– Abdominal pain
– Nausea and vomiting
– Weak and soft bones (esp. in children)
– Vitamin D deficiency

It can also be prescribed to detect any form of cancer in the liver-gallbladder region or in the bones. ALP levels are also used to observe the efficacy of the treatment protocol being followed in order to treat any one of the above-mentioned symptoms or diseases.

What diseases are associated with abnormal ALP levels?

An ALP test can be used to diagnose the following diseases-

– Liver cirrhosis
– Hepatitis
– Cholecystitis
– Bile duct blockage due to inflammation or stones
– Osteomalacia – softening of bones in adults
– Rickets
– Piaget’s disease of the bone – bone destruction and regrowth

What is the price of an ALP test in India?

The average cost of an ALP test is close to Rs 170-200 in India. Since this test is often prescribed along with other liver function tests, the total test package cost might be higher than this.

How is the ALP test performed?

The ALP test is a blood test that follows the basic steps for any other blood test such as CBC or FBS.

– The blood is drawn from the arm by tying a tourniquet around the arm to increase the pressure on the veins.

– Once the vein is found, the healthcare provider will rub a small amount of antiseptic solution on the area and insert the syringe to draw blood.

– Once the blood is drawn and collected in a vial, the tourniquet is removed and the area is cleaned and covered with a sterile bandage.

– You might feel a slight stinging sensation when the blood is being drawn but beyond that, the procedure is relatively pain-free.

– The entire procedure takes just a few minutes. You can go back to home after the test is done.

Does the ALP test require fasting?

Yes, you might be asked to fast 10-12 hours prior to the ALP test. This is because the process of digestion can alter ALP levels. There are certain medications also that can interfere with the ALP enzyme level. So, it is important to inform your doctor about your medical history and the medications that you are on prior to the test.

What are the important precautions I should follow before and after the test?

What is the normal reference range for ALP?

The normal reference range for the ALP test is usually taken as 20-140 IU/L. However, this range may differ from lab to lab.

What do abnormal ALP levels indicate?

High ALP level

– Indicates serious problems with the liver and/or gall bladder.

– It is indicative of hepatitis, cirrhosis, hepatic cancer, blockage of bile ducts, gallbladder stones.

– May also point to the weakness of bones as seen in rickets, Paget’s disease, or bone cancer.

– It could also be due to an overactive parathyroid gland.

A very high ALP level could also be a precursor to bacterial infection, heart diseases, kidney cancer, or mononucleosis. In such cases, a follow-up blood test called ALP isoenzyme test is prescribed to pinpoint the exact problem.

Low ALP level

– Low ALP is rarely seen in individuals undergoing an ALP test

– It could indicate malnutrition due to poor absorption of nutrients in the body.

– Deficiency of certain vitamins such as vitamin D

– Indicative of celiac disease

However, it must be noted that some demography will naturally have higher than normal ALP level.  It is commonly observed that growing kids will have higher ALP level as compared to adults since their bones are still in the growing phase.

What could be other causes of abnormal ALP levels?

Apart from the above-mentioned conditions, abnormal ALP levels could also be linked to

– Anemia
– Ulcerative colitis
– Wilson’s disease
– Breast cancer
– Prostate cancer

What are the risks associated with an ALP test?

This is a relatively simple and safe procedure. The only risks involved here are

– Bruising or infection at the site of needle insertion.

– May cause excessive bleeding in case you have a bleeding disorder or are on blood thinners. It is thus important to inform your doctor beforehand about these.

– In very rare cases, there might be a brief onset of phlebitis or vein inflammation and swelling. You need to inform your doctor about the same if you experience this symptom.

Can pregnant women undergo an ALP test?

In pregnant women, the ALP enzyme is produced by the placenta. High levels of ALP in pregnant women could be because of HELLP syndrome, intrahepatic cholecystitis, or related malignancies. Since ALP levels are related to placental conditions, pregnant women should undergo the ALP test as per the prescription of the doctor.

Is an ALP test conducted for infants and children too?

Conditions of the liver such as cirrhosis or jaundice can cause elevated ALP levels in babies. So, if the need arises, infants and children can undergo the ALP test.