Myelodysplastic syndrome or MDS refers to a group of blood disorders caused by defective blood cell production in the bone marrow. Bone marrow produces immature blood cells called blasts, which over a period of time develop into mature blood cells and divide themselves into red blood cells, white blood cells and platelets. In Myelodysplastic syndrome, these blasts fail to mature and either die in the marrow itself or soon after they reach the blood stream. When there are not enough healthy blood cells, the body becomes weak and is susceptible to infections. MDS is not a cancer, however, in 20 to 30% of patients, the condition may progress itself into cancer and thus this condition was earlier called preleukemia.
Causes of Myelodysplastic syndrome
Based on causes, Myelodysplastic syndrome can be classified into primary MDS and secondary MDS. Myelodysplastic syndrome presenting itself without any known cause is called primary MDS. Myelodysplastic syndrome may also occur due to some known reasons such as history of cancer treatment involving radiation and chemotherapy, exposure to certain industrial chemicals and smoking. When the cause of the MDS condition is known, it is called secondary Myelodysplastic syndrome. Identifying the type of MDS is vital to the treatment as primary MDS has better prognosis when compared to secondary MDS.
Myelodysplastic syndrome does not cause any symptoms in the initial stages of the disease. However, the following warning signs may show up as the disease starts to progress.
Diagnosis and treatment
MDS is diagnosed with the help of blood tests and bone marrow tests. A complete blood test is done to understand the different blood counts. However, blood tests alone cannot detect MDS. Bone marrow tests are conducted to confirm the presence of Myelodysplastic syndrome. This procedure involves taking bone marrow samples from the pelvic bone of the patient by inserting a needle under local anesthesia. Once MDS is determined, the following methods are followed to treat the condition.
Bone Marrow Aspiration
Bone marrow refers to the spongy tissue that is found inside the larger bones such as spine, breast bone, hips, ribs, legs and skull. Marrow has two parts – both solid and liquid. If the solid portion of the bone is sampled, it is called biopsy. Aspiration procedure is used to collect the liquid part of the marrow.
Both the procedures show whether the bone marrow is healthy and making normal amounts of blood cells. This procedure is normally used by doctors to diagnose and monitor blood and marrow diseases, including cancer. In bone marrow aspiration, the doctor uses a needle to draw a sample of the fluid portion. For a biopsy, a larger needle is used to take the sample of the solid part.
Most often bone marrow aspiration and bone biopsy is done at once. Together, they make the bone marrow examination. Although they are different procedures, they offer complementary information about bone marrow cells.
Why is it done?
Bone marrow aspiration and biopsy offer detailed information about the condition of the bone marrow and blood cells. In case the blood tests indicate that cell counts are abnormal, and information is not sufficient about a suspected problem, this is done. The doctor may perform bone marrow exam to diagnose a disease condition involving the bone marrow or blood cells:
Pre bone marrow aspiration procedure
It is imperative to inform the doctor about any medications and supplements the patient is consuming. This can increase the risk of bleeding after a bone marrow aspiration. In case of anxiety or worry, better talk to the health care provider so that a sedative medication could be given before the aspiration in addition to a numbing agent through local anesthesia at the site where the needle is inserted.
Bone marrow aspiration is done in a hospital, a clinic or in a doctor's room. A specialist in blood disorders – a hematologist – or an oncologist, who is a specialist in cancer does the procedure with a nurse and a trained technologist. It usually takes about half an hour for the exam and if any intravenous sedation is given, extra time is taken for pre and post procedure care.
The patient's blood pressure and heart rate are checked. Some form of anesthesia is administered before the bone marrow aspiration as it can be painful. For many, local anesthesia is sufficient. You will be fully awake during the aspiration, but the site is numbed to reduce pain. If you are quite anxious, intravenous IV sedation is given before the marrow procedure.
Bone marrow aspiration procedure
The area for inserting the biopsy needle is marked and cleaned. The bone marrow fluid (aspirate) is usually collected from the top ridge of the back of the hipbone, and if it is done from the breast bone or the front of the hip near the groin. In young children and kids, the sample is taken from the lower leg bone, just below the knee. The patient will be made to lie down on the abdomen or side.
The bone marrow aspiration is usually done before the biopsy. A small incision is made to insert the needle easier. A hollow needle is inserted through the bone and into the bone marrow. Several samples are taken and aspiration takes only a few minutes. While the health care team ensures that sufficient quantity of sample is drawn, sometimes a 'dry tap' may occur, that is fluid cannot be withdrawn. The needle is moved for another attempt.
Post aspiration procedure
After the bone marrow exam, pressure is applied to the where the needle was inserted to stop the bleeding. A smaller bandage is placed on the site. If local anesthesia had been administered the patient is asked to lie back for 10-15 minutes and apply pressure on the biopsy site. In case, IV sedation had been given, you are taken into a recovery area as sedatives may cause impaired judgment, memory lapses or slowed response.
Tenderness may be felt for a week or more after the bone marrow exam, and the doctor administers pain reliever. You need to keep the bandage dry for 24 hours and not shower or bathe, or swim or use the hot tub. It is okay to get the aspiration site wet after 24 hours. In case bleeding soaks through the bandage, or does not stop even with direct pressure, consult the doctor. The doctor also needs to be contacted if there is persistent fever, worsening pain, swelling at the procedure site and increasing redness or drainage at the procedure site. Also it is advised to avoid rigorous activity for a couple of days to minimize bleeding and discomfort.
Results from bone marrow aspiration
The sample is sent to a laboratory for analysis. The results are available in a few days. The pathologist or hematologist evaluates the samples to check the health of the marrow and if it has enough healthy blood cells and also for abnormal cells. The doctor confirms or rules out a diagnosis and how advanced the disease is or if the treatment is working. Sometimes, follow-up tests are done.
Risks of bone marrow examination
This is a safe procedure and complications are rare. But some complications include:
Excessive bleeding which can happen in people with low platelet count.
Infection in those with weakened immune systems.
Discomfort that could be long lasting in the biopsy site.
Heart and lung problems can be caused due to penetration of the breastbone.
Sedation can cause allergic reaction, nausea and irregular heartbeats in some.
Uses of bone marrow exams
These are used for many conditions including:
While problems with bone marrow can create lasting and serious health problems, bone marrow exams, such as aspiration and biopsy are important to help determine the status and extent of problems in the cells to evaluate and determine further treatment and management.
A bone marrow disorder that is mostly inherited, Kostmann's syndrome indicates a severe deficiency in neutrophils. Neutrophil is a type of white blood cell that helps the body fight infections. This condition is referred to as an autosomal recessive disorder of neutrophil production. It is also commonly known as severe congenital neutropenia. This condition leads to recurrent infections right from infancy as this condition is usually diagnosed just after the birth of a baby. Infection of the lungs, sinus glands and liver are common. There are several forms of neutropenia, of which Kostmann's syndrome or congenital neutropenia is common in kids.
People affected with this condition may develop fever and inflammation of the skin and gums. About 40% of the people affected by this disease have decreased bone density thus making the bones brittle. About 20% of the people with this condition are prone to develop leukemia or myelodysplastic syndrome during adolescence. Seizures, heart and genital abnormalities may also be noticed in such patients. If not treated rightly, the condition could prove fatal. The syndrome is named after the Swedish doctor Kostmann who discovered it.
Kids suffering from this condition inherit an abnormal gene from each of their parent. Carriers of the gene do not experience any symptom and so until the child is born the parent wouldn't know that they carried such a gene.
Symptoms of Kostmann's syndrome
Severe neutrophil deficiency
Necrotic ulceration of genital mucosa
Necrotic ulceration of oral mucosa
The disease can be diagnosed with blood tests, genetic testing and bone marrow tests. The physician might administer a substance called granulocyte colony stimulating factor (GCSF). This stimulates the bone marrow to produce more neutrophil. Other forms of treatment include Haematopoietic stem cell transplantation (HSCT), bone marrow transplant and antibiotics.
Bibliography / Reference
Collection of Pages - Last revised Date: January 22, 2019