Alkaline phosphatase is all you need to know: high, low, what it is, bone, normal values ​​and more. Alkaline phosphatase, what it is
It derives from the English acronym ALP or alkaline phosphatase level and is, in summary, an enzyme composed of four different forms: intestinal, hepatobiliary, bone and placental. The latter is present only during gestation. It goes without saying that this enzyme occurs naturally in related organs such as bones, liver, placenta and intestines. Alkaline phosphatase differs from acid phosphatase (ACP) exclusively in relation to the pH in which the two forms operate. Why the alkaline phosphatase test is required
It is a test to detect, in most cases,bone or liver problems . But the alteration of the values ​​could also occur as a result of an incorrect diet , mostly high-protein or poor. There are in fact some nutritional or vitamin deficiencies (for example hypovitaminosis D) which could cause an increase in alkaline phosphatase. Where is alkaline phosphatase found
At the bone level, alkaline phosphatase is produced by special cells called osteoblasts that are used to build bone . While in the liver they are mostly found near the bile ducts. In any organ they are found, however, it should be noted that they reveal themselves in different forms defined isoenzymatic. High alkaline phosphatase, why
First of all, it is important to underline that high alkaline phosphatase (or ALP) is not always high in the presence of particular pathologies. There are many cases in which it could be a momentary and physiological situation. One of the most common is pregnancy, although it must be said that during gestation high values ​​could also indicate a gravidic jaundice . But temporary elevations also occur in growing children, during fracture healing, and in menopause. Diseases related to high alkaline phosphatase
The most frequent liver diseases – detectable through a simple blood test that checks the amount of alkaline phosphatase – aregallstones , liver cirrhosis , jaundice, acute hepatitis and more rarely neoplasms . The reason why alkaline phosphatase elevations occur is that damaged liver cells release large amounts of ALP into the blood. This means that taking medications that can cause liver problems in some way could also increase alkaline phosphatase. It should also be said that if the increase occurs in conjunction with abnormal values ​​of alkaline phosphatase, AST or ALT, it could almost certainly be problems with the hepato / biliary tract. On the skeletal level, however, they could indicate a very high bone turnover(for example in the case of Paget’s disease), but also metastases, osteoporosis, osteomyelitis and hyperparathyroidism. The reasons why alkaline phosphatase could be high
- Gallstones (up to 10-fold average increase)
- Hepatic or bone cancer (increase up to 20 times the normal value)
- Cirrhosis (Minimal increase: about twice normal)
- Hyperprotein diets
- Hepatitis (Minimal increase: about twice normal)
- Fractures
- Kidney failure
- Bone metastases (increase up to 20 times the normal value)
- Liver metastases (increase up to 20 times the normal value)
- myeloma
- Mononucleosis (approximately 3/5 fold increase)
- Paget’s disease
- Osteomielite
- Rickets
- Sarcoidosis (Slight increase)
- Tuberculosis (Slight increase)
How to perform the alkaline phosphatase test
The alkaline phosphatase levels are detected through a blood test to be performed strictly on an empty stomach, preferably in the morning. This is essential because slightly higher than normal levels of phosphatase can occur following meals. When a blood test
is requested It is not always requested if some serious disease is suspected , but it could also be part of routine tests if you take drugs that can damage the liver. Some doctors also request it while taking birth control pills. Drugs that can cause an increase in alkaline phosphatase:
- Acetaminofene
- Valproic acid
- Allopurinolo
- Alotano
- Amiodarone
- Amitriptilina
- Androgens
- Asparaginasi
- Aspirin
- Azathioprine
- Benzodiazepine
- Carbamazepine
- Carbazone
- Chinidina
- Cimetidine
- Chloramfenicolo
- Oral contraceptives
- Dapsone
- Diclofenac
- Disulfiram
- Erythromycin
- Estrogen
- Ethionamide
- Etionamide
- Phenylbutazone
- Phenylbutazone
- Phenytoin
- Phenobarbital
- Phenothiazine
- Fluconazole
- Glyburide,
- Ibuprofen
- Imipramina
- Imipramina
- indomethacin
- Mao inhibitors
- Isoniazide
- Ketoconazole
- cyclosporine
- Mercaptopurina
- Mercaptopurina
- methyldopa
- Methotrexate
- Minosalicylic
- Naprossene
- Papaverine
- Penicillin
- Pyrazinamide
- Probenecid
- Procainamide
- Propiltiouracile
- Rifampicin
- Anabolic Steroids
- Sulfamidici
- Sulfamidici
- Sulfasalazina
- Sulindac
- Tamoxifene
- Tamoxifene
- Tetracicline
- Tolbutamide
- Trimetadiona
What are the normal values ​​of alkaline phosphatase
Males and females have slightly different values, here are those suggested by INRAN:
- Normal values ​​for males
- 4 years: 149-369 U / l
- 5 years: 179-416 U / l
- 6 years: 179-417 U / l
- 7 years: 172-405 U / l
- 8 years: 169-401 U / l
- 9 years: 175-411 U / l
- 10 years: 191-435 U / l
- 11 years: 185-507 U / l
- 12 years: 185-562 U / l
- 13 years: 182-587 U / l
- 14 years: 166-571 U / l
- 15 years: 138-511 U / l
- 16 years: 102-417 U / l
- 17 years: 69-311 U / l
- 18 years: 52-222 U / l
- Adults: 45-115 U / l
- Normal values ​​for females
- 4 years: 169-372 U / l
- 5 years: 162-355 U / l
- 6 years: 169-370 U / l
- 7 years: 183-402 U / l
- 8 years: 199-440 U / l
- 9 years: 212-468 U / l
- 10 years: 215-476 U / l
- 11 years: 178-526 U / l
- 12 years: 133-485 U / l
- 13 years: 120-449 U / l
- 14 years: 153-362 U / l
- 15 years: 75-274 U / l
- 16 years: 61-264 U / l
- 17-23 years: 52-144 U / l
- 24-45 years: 37-98 U / l
- 46-50 years: 39-100 U / l
- 51-55 years: 41-108 U / l
- 56-60 years: 46-118 U / l
- 61-65 years: 50-130 U / l
- over 65 years: 55-142 U / l
If the values ​​are high: how to bring them back to normal
Based on the problem, your doctor will study the best strategy. However, in principle, the values ​​should return to normal by intervening on the pathology in progress – both hepatic and bone. Low alkaline phosphatase: the reasons
If on the one hand high phosphatase could indicate serious diseases, low alkaline phosphatase generally does not cause significant diseases . It can occur in case of anemia , zinc deficiency, menopause , after a blood transfusion, bypass surgery or nutritional deficiencies. More rarely it can be an indication of more serious problems: celiac disease, hypervitaminosis D, cystic fibrosis, hypothyroidism, nephritis, placental insufficiency or hypophosphatasia (associated with high vitamin B6 levels).
