Shchf analysis decoding. Alkaline phosphatase is elevated: what does it mean and how to treat it. Alkaline phosphatase is lowered

The deviation from the norm of indicators of a biochemical blood test worries many patients. To understand why elevated alkaline phosphatase is dangerous, the reasons for its increase in the blood, it is worth understanding what this indicator is.

Alkaline phosphatase - what is it

A group of enzymes involved in the tissue metabolism of phosphorus and calcium are united under the name "alkaline phosphatase" (AP). They split off a phosphorus group from an organic compound and are active only in an alkaline environment. Therefore, the main amount of alkaline phosphatase is in the tissues, and it enters the blood when the cells are destroyed. Normally, aging and cell death occurs regularly and in small amounts, so there is little ALP in the blood.

There are 11 known varieties of enzymes of the phosphatase group, which are found throughout the body. The most important are

hepatic, including from the biliary tract;
bone;
intestinal;
placental;
tumor.

Proper Preparation Before Alkaline Phosphatase Testing

Information about the reliable level of alkaline phosphatase in the blood makes it possible to diagnose serious diseases of the liver, bones and other organs. Therefore, it is extremely important to exclude causes that can distort the result. It is best to get the recommendations of the doctor who ordered the study on this matter.

The material for analysis is venous blood, it is taken in the morning on an empty stomach.

Before the study

do not eat or drink for at least 8 hours (water is no exception);
two days before the analysis, prohibit the use of alcohol;
on the eve and on the day of blood sampling, do not overstrain physically;
do not undergo other instrumental medical or diagnostic procedures before analysis;
a hot bath or shower may affect the result.

the composition of the diet, especially the abundance of fatty foods;
smoking;
taking medications (diuretics, antibiotics, aspirin, allopurinol, paracetamol, oral contraceptives, hypoglycemic drugs).

When is an alkaline phosphatase test ordered?

Doctors consider it necessary to check the level of alkaline phosphatase when

preparation for the operation;
assessment of liver function;
scheduled examinations of patients to assess their health status;
suspicion of liver pathology and complaints of nausea, pain on the right under the ribs, fatigue and lack of appetite;
cholecystitis, cholangitis, gallstones;
bowel and heart diseases.

The norm of alkaline phosphatase in the blood

Normative indicators vary widely and depend on the age, gender and characteristics of the reagents and equipment of the laboratory in which the analysis is performed. In addition, the result can only be evaluated in combination with other clinical and laboratory data of each patient. This can and should be done by the attending physician. Self-diagnosis will only bring unnecessary worries and confusion.

The average value in adults is 80-120 IU / l.

Alkaline phosphatase in children

The norm for children is higher, on average 1.5 times. This is due to the fact that in the process of formation and growth of the skeletal system, bone alkaline phosphatase enters the blood in large quantities.

children under 10 years old - 150-350 IU / l;
children 10-19 years old -55-500 IU / l.

The indicator is more increased in premature babies, whose body works in an enhanced mode.

In adolescence, on average, ALP in boys is slightly higher than in girls.

In pregnant women

ALP normally increases in the third trimester, as the fetus takes away from the mother a large amount of resources for bone formation. The norm is an increase to 240 U / l.

In adulthood

After 50 years, alkaline phosphatase increases slightly - 110-135 IU / l, due to the intensive entry into the blood of the bone variety of the enzyme. This is facilitated by osteoporosis and other degenerative processes.

After 75 years, the norm indicator grows even more - 165-190 IU / l.

Increased alkaline phosphatase: causes

Most often, an increase in alkaline phosphatase in the blood is a marker of damage to liver cells or bones. Rarely, other diseases appear this way. The reasons can be divided into several groups.

Hepatic

Stagnation of bile in the liver. The release of alkaline phosphatase into the blood in this case is due to the obstruction of the outflow of bile due to large stones, inflammation, sclerosis of the bile ducts, squeezing tumor formations, postoperative strictures.
Damage to liver cells. Hepatitis of toxic origin - alcoholic, medicinal - give a more significant increase in the indicator. In viral hepatitis, alkaline phosphatase may be normal or slightly elevated. Diagnosis can be made by examining other liver enzymes.
Tumors of the liver, metastases. Cause a sharp increase in the rate.

Bone

Entry into the blood of a large amount of the bone variety of phosphatase is observed when

fractures, when tissue is destroyed; accretion of fragments is also accompanied by high alkaline phosphatase;
Paget's disease, the course of which requires increased formation of bone tissue instead of destroyed;
bone resorption in hyperparathyroidism; an excessive amount of parathyroid hormone also causes a significant disruption of the metabolism of phosphorus and calcium;
tumor processes, osteogenic sarcoma, metastases;
Hodgkin's disease with damage to bone tissue.

cardiac

Myocardial infarction is accompanied by the death of its cells, therefore, an increase in the cardiac variety of alkaline phosphatase is observed in the blood.
Heart failure (HF) is characterized by venous congestion and edema, leading to liver damage and an increase in hepatic phosphatase in the analysis.
Myocardial tumors significantly impair contractility, cause severe rhythm disturbances. As a result, there are signs of heart failure and liver damage with an increase in alkaline phosphatase.
Tumor metastases to the lungs lead to HF.
PE causes a heart attack of the lung, the death of its cells, and the content of phosphatase in the blood increases.
Arterial hypertension, especially in acute glomerulonephritis, is severe and quickly leads to heart failure with liver damage and an increase in alkaline phosphatase.

Hormonal

Thyrotoxicosis disrupts cardiac activity, contributes to the development of heart failure.
Hyperparathyroidism.

Intestinal

In case of cancer of the stomach and other parts of the gastrointestinal tract, the intestinal variety of phosphatase primarily enters the blood, with the development of the disease, severe liver damage, its atrophy, accompanied by an increase in hepatic alkaline phosphatase, is added.
Metastasis. Carcinoid of the gastrointestinal tract often metastasizes to the heart muscle, causing its damage, the development of heart failure. Occurrence of metastasises in lungs at a cancer of a stomach is characteristic. In this case, the work of the heart also suffers.

Decreased alkaline phosphatase

In pregnant women, this indicator indicates placental insufficiency. If a woman is taking oral contraceptives, ALP may be below normal. The following factors lower the rate:

hypothyroidism;
congenital chondrodystrophy;
excess intake of vitamin D;
lack of zinc, magnesium, vitamin C;
severe anemia, the period after a blood transfusion;
kwashiorcosis (dystrophy, a condition with prolonged restriction of protein in food);
heart failure on the background of anemia;
left ventricular hypertrophy as a result of the metabolic syndrome;
condition after coronary artery bypass grafting.

Also, a decrease in enzyme activity can cause a way to store blood - when it is supercooled, the result is distorted.

Elimination of deviations from the norm in the analysis for the activity of alkaline phosphatase is possible only if their cause is clarified and under the supervision of a doctor who has the necessary experience, knowledge and is aware of all the individual characteristics of the course of the disease in a particular patient.

In the human body, alkaline phosphatase is responsible for transporting phosphorus to all cells and tissues. Its rate is more or less constant. If alkaline phosphatase is elevated, this indicates a violation of phosphorus-calcium metabolism, which, in turn, indicates the development of a pathological process in the body.

Functions

This substance is an enzyme. It belongs to the group of hydrolases. Alkaline phosphatase takes part in dephosphorylation processes. It separates the microelement from organic substances and carries it through cell membranes. As a result, all body tissues receive the necessary amount of phosphorus.

The enzyme is most active in an environment with a pH of 8.6 or more. It is thanks to this that the word “alkaline” is present in its name.

Where is contained

The highest level of the enzyme is observed in the intestinal mucosa, placenta (during pregnancy), mammary glands (during lactation), bone tissue. Almost all body tissues contain alkaline phosphatase. In this regard, it can be: intestinal, hepatic, renal, placental and bone. In addition, the enzyme is found in

Signs of an increase in the indicator

An increase in the level of alkaline phosphatase can occur against the background of both physiological processes and serious pathologies.

In this case, a person experiences the following symptoms:

constant feeling of fatigue;
decreased or complete loss of appetite;
pain in the right hypochondrium;
episodes of nausea;
discomfort in the joints and bones.

The presence of such conditions is the basis for visiting the attending physician. The specialist will prescribe a study, according to the results of which he will be able to assess the composition of the blood. The conclusion also displays the concentration of alkaline phosphatase.

The natural nature of the indicator growth

The concentration of the enzyme can sometimes increase in healthy people. Information regarding what elevated alkaline phosphatase means in each case should be provided by the attending physician.

Nevertheless, it is important to know that an increase in the indicator can occur under the following conditions:

pregnancy;
lactation;
menopause;
beriberi;
unbalanced diet;
intoxication caused by the use of alcoholic beverages.

In addition, elevated alkaline phosphatase in the blood can be observed against the background of long-term use of certain drugs. The list of medicines that affect the growth of the indicator is extensive, it includes several hundred items. In this regard, it is necessary to strictly follow the treatment regimen drawn up by the doctor. An increase in dosage and duration of administration can lead to impaired liver function.

Reasons for the increase in adults

Most often, the level of the enzyme increases in the presence of pathologies, during the development of which bone tissue and liver are damaged.

All causes of elevated alkaline phosphatase are conditionally divided into several groups:

Diseases associated with damage or destruction of liver cells. This also includes ailments characterized by difficulty in the outflow of bile.
Pathology of bone tissue.
Other diseases.

The first group of causes includes the following pathologies:

Cirrhosis. This is a process characterized by inhibition of liver function. This is due to the replacement of normal scar tissue.
Hepatitis. Most often, alkaline phosphatase is elevated in autoimmune and viral forms of the disease. At the same time, the level of the enzyme increases by 3 times.
Malignant neoplasms. The tumor may be primary, that is, localized in the liver. In addition, the cause of an increase in alkaline phosphatase may be the penetration of metastases into the organ (secondary cancer).
Cholangitis. This is a chronic liver disease. Against the background of its development, portal hypertension and liver failure occur.
Biliary cirrhosis (primary). Pathology is a consequence of cholangitis. In its presence, alkaline phosphatase is increased significantly - 4 times. At the same time, even after complete recovery, the indicator decreases for a long time.
Infectious mononucleosis. This is a viral pathology of an acute nature. It is characterized by damage to liver cells. In addition, the composition of the blood changes.
The formation of stones in the bile ducts.
cholestasis. This is a pathological condition in which the bile produced by the liver stagnates.

If alkaline phosphatase is elevated in the blood, this may indicate damage to the bone tissue. The most common causes of an increase in the level of the enzyme are the following diseases:

Osteomalacia. This is a pathology of a systemic nature, characterized by softening of the bones, as well as their deformation. Against the background of its development, vital vitamins and microelements are washed out of the body.
Paget's disease. This is a serious chronic disease. It is characterized by damage to the mechanism of restoration of bone tissue, as a result of which it becomes weak, prone to deformation and destruction.
Osteogenic sarcoma. This is a primary neoplasm of a malignant nature. The tumor forms and develops in the depth of the bone tissue.
Metastases from other organs.

In addition, alkaline phosphatase increases during bone healing after fractures.

Other diseases in which the rate is increased:

Hyperparathyroidism (primary).
Ulcerative colitis.
Myocardial infarction.
Perforation of the intestinal wall.

According to statistics, the most common cause of an increase in alkaline phosphatase is liver disease.

Features of the growth rate in children

The level of the enzyme in the blood of a child is always higher than that of an adult. This situation persists until the onset of puberty. In these cases, it is customary to talk about physiological processes in which there is an intensive growth of bone tissue.

An upward deviation of the indicator may also indicate the presence of the following pathologies:

Diagnostics

If alkaline phosphatase is elevated in a child, the pediatrician will issue a referral to a gastroenterologist. In adults, the initial diagnosis can be made by a therapist.

To detect pathology, the doctor prescribes the following studies:

Analysis of blood, feces and urine. The level of alkaline phosphatase is determined in the biomaterial.
Analysis of isoenzymes in the blood serum or amniotic fluid (in pregnant women).
Assessment of alkaline phosphatase activity in the juice of the small intestine.

The following values are normal (expressed in IU/L):

Children under the age of 10 years - 150-350.
Persons from 10 to 19 years old - 155-500.
Adults under the age of 50 - 30-120.
Persons from 50 to 75 years old - 110-135.
Elderly people (over 75 years old) - 165-190.

In order to understand which organ is involved in the pathological process, the doctor may prescribe additional studies. As a rule, this is an analysis for alanine aminotransferase and aspartate aminotransferase. If, against the background of an increase in alkaline phosphatase, they are also rejected upwards, this indicates liver damage. If the analysis of the patient's biomaterial showed an increase in phosphorus and calcium, it is customary to talk about diseases of the bone tissue.

Thus, according to the results of complex diagnostics, it will become clear which pathology development provoked an increase in the level of the enzyme.

Treatment

It is important to understand that the upward deviation of the alkaline phosphatase index is not an independent disease. This is just a symptom that indicates the development of a disease. In this regard, it is impossible to normalize the level of the enzyme in the blood without eliminating the underlying disease.

In most cases, an increase in alkaline phosphatase indicates liver damage. In diseases of this organ, it is necessary to strictly follow a diet in order to provide it with functional rest. To do this, you need to exclude fresh bread, flour products, sour fruits and berries, legumes, fatty meats, carbonated and alcohol-containing drinks, spices, chocolate from the diet. All dishes must be boiled, stewed, baked or steamed. In addition, the patient is shown taking drugs designed to restore the normal functioning of the liver (hepatoprotectors).

Regardless of what pathology caused the increase in the level of the enzyme, its treatment should be strictly under the supervision of a doctor. This will reduce the duration of therapy and significantly reduce the risk of complications. Based on the results of the diagnosis, the doctor can refer the patient for further treatment to narrow specialists - a gastroenterologist, orthopedist, oncologist, surgeon, cardiologist.

Prevention

There are no specific measures to prevent the development of the pathological process. In order to minimize the risk of its occurrence, it is recommended:

Finally

Alkaline phosphatase is the enzyme responsible for delivering phosphorus to the body's cells. As a rule, its indicator changes only against the background of growing up. If the blood test indicates that alkaline phosphatase is elevated, what does this mean? This result is an alarming sign, since an increase in the level of the enzyme in most cases indicates a pathology of the liver, bone tissue or bile ducts. To identify the underlying disease, a comprehensive diagnosis is required.

Alkaline phosphatase (AP) is a protein enzyme that is present in all tissues of the body and, in an alkaline environment, ensures normal metabolism at the cellular level. In a biochemical blood test, an increase in alkaline phosphatase indicates diseases of the hepatobiliary and skeletal systems.

Allocate total (ALP), hepatic (ALPL), bone (FLPL) and intestinal (ALPI) alkaline phosphatase, which is involved in phosphorus-calcium metabolism in the body and performs the following functions:

participates in the hydrolysis of phosphoric acid;
promotes the transport of phosphorus from the intercellular space to the cells of internal organs and tissues;
affects the processes of calcium deposition and promotes bone growth;
participates in lipid metabolism.

Indications for analysis

A blood test for alkaline phosphatase is included in the liver tests of a biochemical study and is prescribed for the diagnosis of diseases in the presence of symptoms indicating:

violation of the liver (jaundice of the skin, mucous membranes and eyes, constant itching of the skin, pain in the right hypochondrium);
pathology of the biliary tract (indigestion, nausea, vomiting, diarrhea, discoloration of feces);
destructive changes in bones (pain in the limbs at night and during physical exertion, stiffness of movements, frequent fractures and prolonged healing).

Also, the indicator of alkaline phosphatase is taken into account to assess the work of the liver before surgical interventions, in cases of using general anesthesia, and in the treatment of rickets in children to determine the dosage of vitamin D.

In order for the result of the study to reflect the exact level of alkaline phosphatase in the blood, you should follow the general rules for preparing for the analysis:

donate blood on an empty stomach in the morning;
exclude the use of any medications before the study;
for 12 hours to exclude the use of alcohol and fatty foods,

ALP norm by age (table)

The level of alkaline phosphatase depends on age, gender and blood type. In persons with I and III blood groups and in men, the rate of alkaline phosphatase is higher than in women. After reaching puberty, the concentration of the enzyme in the blood gradually decreases.

Age, years	The norm in men, U / l	The norm in women, U / l
Up to a year	134-518
1-5	156-349
6-10	150-380
10-13	141-460
13-15	127-517	62-280
15-17	89-365	54-128
17-19	85-245	50-104
Over 20	48-95	59-164

In children, in the process of intensive growth and development of the skeletal system, the rate of alkaline phosphatase in the blood is several times higher than in adults, especially during the first 5 years and in adolescence (12-15 years).

Depending on the research method, units of measurement and the reagents used, the reference values of alkaline phosphatase may differ, therefore, when deciphering the results, it is necessary to focus solely on the analysis form.

Causes of an increase in alkaline phosphatase

Diseases that can cause an increase in alkaline phosphatase in the blood are divided into several categories depending on the characteristics of the development of pathological processes in the body.

Diseases of the liver and biliary tract

Increased alkaline phosphatase in the blood can be caused by cholestasis (reduction or cessation of bile flow into the duodenum) or a violation of the liver, which is observed in such diseases:

As a result of pathological processes in the bone tissue, there is an increase in the level of alkaline phosphatase in the blood, due to a violation of the formation of young and destruction of old cells, as well as bone mineralization, which indicates the development of such diseases of the skeletal system as:

bone metastases in the late stages of oncological diseases - occur after the spread of malignant cells with blood and lymph flow;
Paget's disease (osteodystrophy) - a violation of the processes of cell renewal of bone tissue, leading to deformation and fragility of bones;
osteogenic sarcoma - a malignant degeneration of osteoblasts and osteoclasts (immature bone cells) into a tumor that spreads to other tissues of the internal organs;
hyperparathyroidism - increased function of the parathyroid glands, leading to a violation of calcium metabolism in the body;
hyperthyroidism - an increase in the production of thyroid hormones. Serious consequences of the pathology are resorption and a decrease in bone density, as well as a decrease in calcium absorption;
osteomalacia - a decrease in bone density due to improper mineral metabolism and deficiency of phosphoric acid, calcium salts and vitamins in the body.

Infectious diseases

In some cases, alkaline phosphatase is elevated as a result of the development of viral and bacterial infections that adversely affect metabolic processes in the liver, causing inflammation and destruction of the organ, namely:

viral hepatitis (A, B) - accompanied by inflammation due to the multiplication of virus cells in hepatocytes, and in some cases lead to cirrhosis;
osteomyelitis - inflammation of the bone marrow with complications such as fractures, purulent arthritis, malignant degeneration of tissues;
infectious mononucleosis - damage to the lymph nodes, spleen and liver caused by the Epstein-Barr virus;
intra-abdominal infections - caused by the penetration of bacteria into the sterile cavity of the peritoneum, including the liver, kidneys, gallbladder with the formation of inflammatory processes.

Oncological diseases

Diseases accompanied by the development of tumors and metastases that do not directly affect the liver, but can cause an increase in alkaline phosphatase as a result of a violation of metabolic processes and phosphorus-calcium metabolism, namely:

Hodgkin's lymphoma (lifogranulomatosis) - damage to the lymphatic system of the body with possible growth in the form of metastases, which leads to an increase in the liver, spleen, as well as a deterioration in the blood supply to the bone marrow;
myeloid metaplasia - proliferation of cells of tubular bones, liver, lymph nodes and spleen;
cancer of the extrahepatic bile ducts - develops as a result of cholelithiasis or with abnormalities in the structure of the bile ducts (common hepatic or bile duct).

Also, an increase in alkaline phosphatase in the blood can occur under the influence of external factors (malnutrition, long-term treatment), namely:

calorie deficit, starvation;
lack of calcium and phosphates in food;
an overdose of vitamin C;
fracture healing;
the use of drugs (aspirin, paracetamol, antibiotics, oral contraceptives, sulfonamides).

With menopause

Increased levels of alkaline phosphatase during menopause can be caused by changes in hormonal levels and a decrease in the absorption of minerals necessary to maintain the chemical composition of the bones, as a result of which postmenstrual osteoporosis develops - a significant decrease in the number and density of bone tissue.

To prevent the development of postmenstrual osteoporosis, women over 50 are advised to check the level of:

bone alkaline phosphatase,
hydroxyproline,
osteocalcin,
pyridinoline,
phosphates
calcium.

Reasons for the downgrade

In some cases, alkaline phosphatase drops below normal and leads to a violation of mineral metabolism, an increase in the content of inorganic compounds of phosphorus, copper and other elements in the body, to the gradual destruction of bone tissue, and manifests itself as a result of such reasons as:

Deficiency of micro- and macronutrients can cause a decrease in alkaline phosphatase (especially in children with an increased need for nutrients for growth). Deficiency causes both malnutrition and problems with absorption of nutrients from food, such as celiac disease, irritable bowel syndrome, lactose intolerance.
Hypophosphatasia. Mutation of the gene involved in the production of alkaline phosphatase leads to critically low levels of alkaline phosphatase, which negatively affects the condition of bones and teeth. In infants with hypophosphatasia, inorganic phosphorus salts accumulate in the body, which inhibit the process of bone mineralization.
Hypothyroidism. The lack of thyroid hormones leads to a decrease in the production of alkaline phosphatase.

During pregnancy

During pregnancy, the level of alkaline phosphatase gradually increases in proportion to the growth of the fetus and placenta, the tissues of which additionally produce a significant amount of the enzyme (more than 40%). The ALP index returns to normal within a month after childbirth.

If during pregnancy alkaline phosphatase rises above the norm, then this may indicate the development of serious pathologies:

preeclampsia;
pathology of the functioning of the placenta;
stagnation of bile;
disruption of the liver;
bone diseases.

With an increased level of alkaline phosphatase during pregnancy, an additional diagnosis of the state of the hepatobiliary system is required to prevent diseases of the liver, biliary tract and bladder, which is carried out using such studies as:

AST and ALT are enzymes for the metabolism of amino acids in the body. Elevated rates indicate a violation of the functioning of the hepatobiliary system;
Calcium, phosphorus - increase with infectious mononucleosis and bone damage.

In children

In some cases, a high level of alkaline phosphatase in children, as well as in adults, manifests itself in violation of liver functions caused by hepatitis A (Botkin's disease) or mononucleosis (Epstein-Barr virus), as the most common infections in childhood.

In infancy, especially in premature babies, bone diseases may develop, in particular rickets, a violation of bone mineralization caused by a deficiency of vitamin D or a decrease in the absorption of minerals.

Also, the indicators of the enzyme in a child can be increased as a result of the use of drugs for fever (iburofen) and antibiotics (levomycetin, oxacillin, tetracycline, sulfonamides in combinations).

Doctors often prescribe one or another biochemical blood test, but if you have heard of most of them at least once throughout your life, then an alkaline phosphatase test almost always takes you by surprise. What is it and why is it being studied? Why is alkaline phosphatase elevated in the blood?

What is alkaline phosphatase?

This is an enzyme that cleaves phosphate from a molecule of substances of organic origin. It is especially active in an alkaline environment - this is the reason for its name. A small amount of alkaline phosphatase is found throughout the body. Most of this enzyme is in the liver, bone tissue and placenta.

A small amount of the enzyme in the blood is considered the norm, since cells tend to constantly renew themselves. But if they die in large numbers, then the analysis reveals that alkaline phosphatase in the blood is elevated. The reasons for this phenomenon are varied. If the indicators differ significantly from the norm, then one can suspect the pathology of the bones, intestines, liver, or a malignant process in the body.

The norms of this enzyme depend on the age and gender of the person. In children, ALP is normally higher than in adults, and in women it is lower than in men. On average, normal levels of phosphatase in the blood range from 20 to 140 International units per liter.

When is an alkaline phosphatase test ordered?

Analysis for alkaline phosphatase may be included in the list of mandatory studies for certain categories of workers who have contact with harmful substances, and during preventive examinations. Alkaline phosphatase analysis may be prescribed in preparation for surgery. It is also determined to assess liver function or diagnose jaundice.

This study can clarify the situation with pain in the abdomen, in the right hypochondrium, itching of the skin, weakness, loss of appetite, nausea, vomiting, bone lesions. With these pathological processes, alkaline phosphatase is increased.

The influence of negative factors on alkaline phosphatase

There are factors that can affect the result of the analysis, that is, it will indicate a pathology, but in fact it may not be in the body. Circumstances leading to a false positive result include:

period of healing of fractures;
pregnancy;
time of active bone growth;
some medicinal substances that affect the activity of the enzyme: Paracetamol, antibiotics, acetylsalicylic acid;

Increased alkaline phosphatase with errors at the preanalytical stage, for example, if the blood was cooled. When taking hormonal contraceptives, the indicator may decrease.

Why is alkaline phosphatase elevated?

The results of the analyzes sometimes discourage us. Not always a person is ready to accept that he has some kind of health problem. Increased alkaline phosphatase in the blood - what does it mean? Most often, this indicates a pathology of the liver or biliary tract. The reasons include obstructive jaundice, which is associated with impaired patency of the biliary tract. If alkaline phosphatase is elevated, then this may indicate stones in the gallbladder, as well as scars of the biliary tract after surgery. A high level of the enzyme sometimes indicates cancer, cirrhosis, hepatitis, or a malignant process in the stomach.

Strongly increased alkaline phosphatase in liver cancer and metastasis in it. Among infectious diseases in which the enzyme index increases, infectious mononucleosis can be noted.

Alkaline phosphatase is also elevated in bone lesions. There is an increase in the level of this indicator in hyperparathyroidism, myocardial infarction, intestinal perforations, ulcerative colitis.

An increase in an enzyme found in bone tissue

Why is alkaline phosphatase increased in bone tissue? The fact is that the bone tissue of this enzyme contains quite a lot, so it reacts to any changes in the bones. Bone ALP is secreted by osteoblasts, which are large cells with a single nucleus. They are located directly on the surface of the bone tissue, and it is in these places that its intensive formation occurs. Most of all, alkaline phosphatase increases in Paget's disease, which is characterized by excessive growth of bone tissue and a violation of its very structure.

If osteosarcoma develops or bone metastases appear, then alkaline phosphatase also rises. When there is not enough calcium in the body, the bones begin to soften. The enzyme is sensitive to this process, which is also called osteomalacia, in connection with this, its level in the blood rises.

Bone ALP increases during bone growth and fusion, so it is significantly higher in children and adolescents than in more mature patients. Its increase is observed with fractures.

Why does hepatic alkaline phosphatase increase?

Alkaline phosphatase is found in large quantities in the liver, so any changes in its work are reflected in the levels of the enzyme in the blood serum. It begins to be released in large quantities from hepatocytes, which is reflected in the blood picture, including in the analysis for alkaline phosphatase. Quite often, an increase in the enzyme indicates damage to the liver cells or a violation of the functions of the liver itself.

Decreased alkaline phosphatase

ALP is not only increased, but also the level of this substance can be significantly reduced. It is also associated with any disease.

One such disease is hypophosphatasemia. This is a hereditary pathology, which lies in the fact that phosphatase is constantly excreted in the urine. Enhanced release of the body from this substance leads to its acute deficiency.

Hypothyroidism is another disease in which the level of alkaline phosphatase in the blood decreases. With a decrease in the activity of the thyroid gland, due to a lack of certain trace elements, the production of phosphatase also undergoes changes, which then affect human health.

Lack of vitamin B12, C, zinc or folic acid can also lead to a decrease in alkaline phosphatase. This disease is called pernicious anemia. Sometimes this substance can decrease with a lack of growth hormone in children.

Special attention is paid to the condition of the placenta during fetal maturation. If alkaline phosphatase in the blood of a pregnant woman is lowered, then this indicates that the placenta is developing defectively. It is a vital organ for the health of the child, so you need to monitor the performance of this substance in expectant mothers.

Lowered and increased alkaline phosphatase in the blood: what does this mean? We have already decided and found out what the consequences of fluctuations in this substance can be. Be healthy!

Alkaline phosphatase (ALP, ALP) is a parameter of a biochemical blood test, which patients usually indifferently ignore with their eyes due to its “incomprehensibility”. More attention goes to parameters with familiar, familiar names - total protein, urea, glucose, total choleste
rin. Meanwhile, ALP in biochemical analysis is a very important marker that can tell a lot about the patient's health status to a diagnostician.

What is alkaline phosphatase?

Alkaline phosphatase is an enzyme (a special substance, without which the course of biochemical reactions in the human body will become impossible, in inorganic chemistry another word is used in the same meaning - catalyst). ALP is an enzyme from the group of hydrolases. Hydrolases are a large family of enzymes, the distinguishing ability of which is the breaking of intramolecular bonds of various organic compounds with the help of water molecules. There are 6 large groups of hydrolases: phosphatases, glycosidases, esterases, lipases, peptidases, nucleases.

Phosphatase classification

In biochemistry, phosphatases are divided into two types - acidic and alkaline. The conditional middle of the hydrogen ion concentration index in “PH” solutions for a person will be 5.5 (the absolute value is 5.0). Less than 5.5 is an acidic environment, the location of acid phosphatase activity. More than 5.5 - alkaline environment, the location of the activity of alkaline phosphatases. Alkaline human phosphatases show the highest activity in the range of 8.5-10.0 pH index.

ALP is the most abundant enzyme in the human body and can be found in any tissue in the human body. Human alkaline phosphatase is not one homogeneous enzyme, but a group of biologically active substances, having a common generic affiliation, they at the same time differ from each other in their selective effect on a certain type of cell.

Subspecies (isoforms) of human alkaline phosphatase:

ALPI - intestinal;
ALPL - non-specific (located in the liver, bone and kidney tissues);
ALPP - placental.

Although a biochemical blood test can detect any subtype of alkaline phosphatase, another alternative analysis method, the “kinetic colorimetric method”, can be used in clinical studies. Its undoubted advantage will be a clear differentiation of enzymes according to classes and isoforms. It is not worth opposing methods, each of the methods has its own advantages.

Functions of alkaline phosphatase in the human body

The main function of ALP is participation in phosphorus-calcium metabolism, the enzyme facilitates the transport of phosphorus to body tissues, thus regulating the calcium content in the human body.
The secondary functions of alkaline phosphatase are participation in the secretory work of the liver and the growth of bone tissue. The bile produced by liver cells contains molecules of phospholipids, alkaloids, proteins, nucleotides - organic compounds that have phosphatases in their composition. They got into the bile because the body did not have time to use and protect them. ALP helps to separate phosphatase from these compounds, breaks them down, performing a dual useful function - it neutralizes and utilizes these substances. Osteoblast cells, responsible for the “building” of bone tissue, contain the most alkaline phosphatase in the body after the liver. These cells need alkaline phosphatase to structure calcium molecules in bone tissue - phosphatase supplied by alkaline phosphatase acts as a catalyst for this process.

What role does phosphorus and calcium play in the human body?

Calcium and Phosphorus are two inseparable chemical elements in the human body. Their connection is dialectical in nature - one element determines the comprehensibility of the other. The mediator in this process is vitamin D, alkaline and acid phosphatases. The approximate ratio of phosphorus to calcium in the body is 1:3.5 (for an adult, it is 650 g of phosphorus and 2200 g of calcium).

This chemical element is the most important building material from which the human body builds itself. Calcium is part of bone, dental, muscle tissue. With the help of calcium, nails are formed, the smooth muscles of blood vessels are strengthened. In nature, there is a structural twin of calcium - strontium. This metal, in case of calcium deficiency, becomes its substitute. As a building material, strontium is significantly inferior to calcium, and therefore tissues consisting of strontium will be inferior to those made on the basis of calcium - blood vessels, nails, teeth will become brittle and brittle, muscles will lose some of their tone, various growths, processes will appear on the bones. It is not an excess of calcium that is to blame for the deposition of so-called “salts” in the bones, but, on the contrary, a deficiency - the body compensates for the missing calcium with strontium, which, as a rule, is always in excess.

Attention! Phosphorus is needed for the absorption of calcium, a lack of phosphorus leads to a decrease in the absorption of calcium and, accordingly, the level of this chemical element is rapidly falling in the body. For the assimilation of strontium, phosphorus is needed much less than for the assimilation of calcium. Therefore, the body, in case of a lack of phosphorus, switches to an economical mode, forming its tissues from what is, and not from what is needed.

Phosphorus

After calcium, phosphorus is the most important building material. This chemical element is part of bones, teeth, fats (phospholipids), enzymes and proteins.

Phosphorus is the most important participant in energy metabolism in the human body. Such an organic compound as ATP, splitting into ADP, gives the human body the energy necessary for its existence.

DNA and RNA molecules responsible for the storage and transmission of temporal and hereditary information contain phosphate groups that ensure the stability of their structure.

Attention! The normal content of phosphorus in the body will reduce the risk of rheumatoid factor, reduce the likelihood of arthritis and arthrosis, provide clarity and purity of thinking, and reduce the pain threshold.

ALP norms in children and adults

To understand what the numbers mean in the values of alkaline phosphatase in a biochemical blood test, you need to know the normal range, according to which it will be possible to determine the increased and decreased values of the content of this enzyme.

children from 8 to 10 years old - 150-355 U / l;
children from 10 to 19 years old - 158-500 U / l;
adults under the age of 50 years - 85-120 U / l;
adults from 50 to 75 years old - 110-138 U / l;
people over 75 years old - from 168-188 U / l.

Possible pathologies associated with a change in the norm of alkaline phosphatase in the results of a biochemical blood test

Before proceeding to a review of the possible pathological causes of changes in the level of ALP in biochemical analysis, we note several significant features that patients need to know.

Alkaline phosphatase is elevated in children. In the children's body, there are rapid metabolic processes associated with the growth of the body. Considering the role that ALP plays in the human body - the growth of bone tissue, the stabilization of the liver - it is not surprising that there is a lot of this enzyme in the blood of a child. Naturally, the younger the child, the more active such processes are. Upon completion of the hormonal restructuring of the body at 17-19 years (men) and 15-17 years (women), the level of alkaline phosphatase in the human body begins to decline. After 24-25 years, alkaline phosphatase in the human body is used not so much for tissue growth, but for maintaining their health.

Alkaline phosphatase is increased in women during gestation - the formation of a fetus in a woman's body requires a significant amount of various substances - trace elements, proteins, fats, which, accordingly, causes an increase in the number of enzymes responsible for their digestibility. Therefore, the level of alkaline phosphatase in the blood of a pregnant woman increases.

Important! A high level of alkaline phosphatase in children and pregnant women is completely natural, we are not talking about pathology in such cases.

Elevated alkaline phosphatase

Considering the fact that most alkaline phosphatase is found in bone and liver cells, an increased level of this enzyme will indicate a high probability that there are problems with the liver and bone tissue - the death of liver cells, the breakdown of bone tissue will release excess of this enzyme into the blood. All sorts of diseases of the liver (hepatitis of various etiologies, liver injuries) and bone tissue (osteitis of various etiologies, bone injuries and fractures) will become the main suspects in a diagnostician who sees a high level of alkaline phosphatase in the results of a patient's analysis. In addition to the indicated pathologies, a high level of alkaline phosphatase in the patient's blood can have quite banal reasons, for example, a lack of phosphorus and calcium in the diet.

Decreased alkaline phosphatase

A reduced level of alkaline phosphatase is most often associated with metabolic disorders and wear and tear of the body:

osteoporosis;
anemia;
starvation;
excess vitamin D (often observed in children due to the uncontrolled use of dietary supplements containing this coenzyme);
violation of the secretory function of the thyroid gland;
lack of vitamin C (scurvy).