Bone marrow examination is the most informative method for diagnosing diseases associated with its defeat. This substance is located in the tubular and flat bones of the body. It is in it that the formation of stem cells occurs, which are capable of further differentiation into mature blood cells. Most often, bone marrow analysis is performed to confirm or refute the diagnosis of blood cancer.
Indications for the procedure
What is bone marrow analysis done for? Only with this method can you diagnose blood diseases in the early stages. Therefore, doctors refer the patient to the study if he has the following conditions:
- a decrease in the number of red blood cells and hemoglobin (anemia);
- an increase in the number of leukocytes (leukocytosis);
- increased platelet count (thrombocytosis);
- decrease in platelet count (thrombocytopenia);
- suspected malignant blood diseases: blood cancer (leukemia), myelodysplastic syndrome, paraproteinemia;
- suspicion of the presence of metastases in the bone marrow with oncology of other organs.
Bone marrow examination is an invasive procedure associated with damage to the skin and requiring highly qualified specialist. Therefore, this method is used only when strictly necessary. Only when the other diagnostic methods are uninformative, or the patient is most likely to have blood cancer, does the doctor send the patient to undergo a bone marrow analysis.
Also, this method is done to control the treatment of the disease. Then the analysis is carried out before and after the course of therapy.
A puncture is done to find out if bone marrow tissue is suitable for transplantation.
Technique of the procedure: first stage
The essence of the method is to pierce the bone with the taking of the material and its subsequent examination using a microscope. That is, a bone marrow puncture and analysis are performed.
A puncture is made with a special hollow needle in the middle of the sternum at the level of attachment of the third rib. At this point, the bone is most malleable.
The needle should be dry and sterile. All clothes above the waist are removed from the patient. After the puncture site is treated with an antiseptic solution. Men shave their chest hair.
To prevent too deep penetration of the needle, a fuse is put on it. The depth of its fixation is selected individually depending on the thickness of the subcutaneous fat of the patient, his age.
The needle is inserted simultaneously, perpendicular to the patient’s body. With the right technique, a sense of failure should appear. In order for the bone marrow to be taken for examination, the needle must be fixed absolutely motionless. With cancer metastases in the bone, inflammation of the bone tissue (osteomyelitis), this is difficult to achieve. Then the fuse must be shifted higher, and the needle should be moved a little deeper.
Next, a syringe clings to the needle and the bone marrow is sucked up in a minimal volume (1 ml).
At this point, the first stage of bone marrow analysis is almost over. The doctor only had to remove the needle and seal the puncture site with a band-aid.
Technique of the procedure: second stage
The next step is the actual study of bone marrow. Under the microscope, his cells are carefully examined. For this, the material is placed on a glass slide. Since the bone marrow tends to curl quickly, the surface of the glass is wiped with sodium citrate.
This analysis allows not only to diagnose bone marrow cancer, but also to establish its type. The tactics of further treatment and the prognosis for recovery will depend on the results obtained.
Features of trepanobiopsy
The disadvantage of bone marrow puncture is that the material is taken from its liquid part. Therefore, the likelihood of its mixing with blood increases. This can distort the end results.
Trepanobiopsy is a method for analyzing the solid part of the bone marrow. For its implementation, a trocar is used. This tool is similar to a needle for sternal puncture, but large.
In this case, the puncture is not done in the sternum, but in the superior iliac spine. The patient is lying on his side or on his stomach. The doctor sets the needle perpendicularly and sharply inserts it into the bone with rotational movements. Preliminary local anesthesia.
After taking the material, one part is placed on a glass slide, the other in a bottle with formalin.
The disadvantage of the procedure is its duration. It takes about 20 minutes, and all this time the patient should lie absolutely still.
Some time after the procedure, pain in the puncture area is possible. However, they are well removed by anti-inflammatory drugs (Nimesulide, Paracetamol).
Puncture of other bones
Blood cancer is one of the most common oncological diseases in children. How is bone marrow puncture and analysis done for children?
Since the sternum is softer and more pliable in children than in adults, complications in the form of a puncture through it are more likely to develop. Therefore, for small patients, other bones are selected for bone marrow harvesting. Most often - femoral.
A puncture is done in the area of the bone, which is located closer to the pelvis. The patient lies on the opposite side. The doctor punctures not perpendicularly, but at an angle of 60 ° to the femur.
You can also make a puncture over the knee. In this case, the patient also lies on his side, and a roller is placed under the knee. The needle is inserted to a depth of 2 cm after preliminary anesthesia.
Types of bone marrow examination
As already mentioned above, after taking the material from the bone, it is sent to the laboratory for further research. There are two methods of analysis under the microscope: cytological and histological.
The results of the cytological analysis are ready the next day. From them, the doctor learns about the type of cells that are in the patient’s bone marrow, their number, and features of shape and structure.
Histological analysis takes longer (up to 10 days), but is more informative. With its help, you can not only learn about the structure of cells, but also about their environment (collagen fibers, vessels, intercellular fluid).
After the puncture, the doctor will recognize the following bone marrow analysis indicators:
- structural features of hematopoietic tissue cells;
- the number of these cells, their percentage;
- the presence or absence of pathology;
- the number of blast cells, that is, those that should further turn into mature blood cells.
The latter indicator is especially important in the diagnosis of acute leukemia. With this pathology, a sharp increase in their number is characteristic.
Actions after the procedure
Bone marrow analysis is a serious procedure. At least an hour after it, the doctor carefully monitors the patient. He checks the level of blood pressure, pulse, measures the temperature and monitors the general condition.
The patient can return home on the day of the procedure. But he must exclude hard physical labor, not drive, as this will lead to a deterioration in overall health.
To prevent deterioration after a puncture, the patient must adhere to a number of rules:
- exclude alcohol and smoking for several days after the procedure;
- cancel bathing for three days;
- taking any medications must be agreed with the doctor;
- folk treatment should also be agreed.
The hole after the puncture does not need to be treated with alcohol, brilliant green or any other antiseptics.
Possible complications
Difficulties in the analysis are extremely rare if they are performed by a qualified specialist. Much depends on how the bone marrow is taken for analysis, whether sterility is maintained, or the technique is correct.
In violation of aseptic conditions, infection can enter the patient's body.
Overly sensitive patients may pass out. In the worst case, a sharp drop in blood pressure with the development of shock is possible.
If the doctor violates the procedure, this leads to a fracture of the sternum or its through puncture.
All in all, this is a truly safe and harmless procedure. It is widely mastered by most doctors. Therefore, the correct preparation of the patient in most cases allows you to get rid of unwanted phenomena.
Bone Marrow Cancer: A Blood Test
What other diagnostic methods, except for puncture and trepanobiopsy, are used to make a diagnosis?
First of all, the doctor should conduct a thorough conversation with the patient. Only after a detailed analysis of complaints, medical history, heredity, additional examination methods are prescribed.
First, a general blood test is done. It allows you to see the number of blood cells (white blood cells, platelets and red blood cells), the percentage of different forms of white blood cells, or a white blood cell formula.
Next, a biochemical blood test is performed, determining the presence of tumor markers in it.
Other diagnostic methods
In addition to diagnosing bone marrow cancer with blood tests, the following tests are used:
- general urine analysis - to determine the health of the kidneys;
- radiography of the chest cavity - to search for metastases or, conversely, localization of the primary tumor;
- computed tomography and magnetic resonance imaging - a more informative method of searching for metastases;
- scintigraphy, the essence of which is the accumulation of a radioactive drug in the tumor cells.
But only a bone marrow analysis allows you to make a final diagnosis, as well as to clarify the type of cancer.
Blood changes in acute leukemia
Acute leukemia is a form of bone marrow cancer. In this disease, blast cells in the bone marrow are completely deprived of the ability to turn into mature blood cells. Therefore, there is an excessive number of blasts and a decreased level of blood cells.
The indicators of a blood test for bone marrow cancer by the type of acute leukemia are characterized by the following features:
- A progressive decrease in the number of red blood cells and hemoglobin. Red blood cells are reduced to 1 × 10 12 / L, with a norm of 5-5.5 × 10 12 / L. The hemoglobin level drops to 30-50 g / l with a norm of 140-150 g / l.
- Platelets are reduced to 20 × 10 9 / L, normally they should be 200-400 × 10 9 / L.
- The level of leukocytes may vary depending on the form of leukemia. Leukopenic forms are more common, with them leukocytes are reduced to 0.1-0.3 × 10 9 / l (normal - 4-9 × 10 9 / l).
- Up to 99% of blast cells are observed at a rate of 1-5%.
There are forms of acute leukemia in which blasts are not detected in the blood. Then they talk about the aleukemic form of the disease. In such cases, the diagnosis is difficult. To distinguish leukemia from aplastic anemia, only a bone marrow examination will help.
Blood changes in chronic leukemia
The results of a blood test for chronic leukemia depend on the type of disease. Myeloid leukemia and lymphocytic leukemia are distinguished.
Blood counts, like symptoms, in bone marrow cancer by type of chronic myelogenous leukemia depend on the stage of the disease. At the initial stage, when the patient is practically not worried about anything, a slight increase in the level of leukocytes is detected in the blood (20.0-30.0 × 10 9 / L). But at this stage, the diagnosis is rarely made, as the patient simply has no reason to consult a doctor.
Most often, help is needed already in the more advanced stages, with the addition of intoxication syndrome. Then the level of leukocytes reaches 200.0-300.0 × 10 9 / L. A large number of young forms of white blood cells (promyelocytes, myelocytes) appear.
In the terminal stages, when the patient’s condition worsens, a decrease in platelet count (10–20 × 10 9 / L) can be seen in the analysis of the blood.
In chronic lymphocytic leukemia, the number of lymphocytes increases. This is a form of white blood cells. The level of the latter also rises slightly. If timely therapy is not carried out, leukocytosis increases and reaches the same figures as with melleukemia.
Summary
A complete blood count is an informative method for diagnosing bone marrow cancer or leukemia. But only a cytological and histological examination of the bone marrow allows you to establish an accurate diagnosis. This is an affordable and highly informative method.
Despite the frightening at first glance, the technique, this technique is absolutely painless and almost harmless. Only in extraordinary cases can complications develop.
Therefore, each patient to whom the doctor prescribed a bone marrow analysis must undergo this examination. After all, the benefits of it many times exceed the possible harm.