Showing posts with label blood diseases. Show all posts
Showing posts with label blood diseases. Show all posts

Monday, December 12, 2011

Blood Disorder: Paroxysmal Nocturnal Hemoglobinuria

PNH is not a cancer but blood disease and is treated at cancer facility. PNH is a rare disease and can become life threatening. Another name for PNH is Marchiafava-Micheli syndrome characterized by complement-induced intravascular hemolytic anemia , red urine and thrombosis. 
Since this is a blood disease it will be usually treated by a Hematology Oncologist.  The disease,PNH, is different from other hemolytic anemias because the cause is from an intrinsic defect.  Intrinsic defect means that in the cell membrane (deficiency of glycophosphatidylinositol) leading to absence of protective proteins on the membrane.
Paroxysmal nocturnal hemoglobinuria (PNH) results from a mutation in a hematopoietic stem cell; the mutated cell then expands in the bone marrow. This mutation is usually acquired in adulthood, and the disorder is not inherited or passed down to children.
The disease causes the breakdown of circulating red cells (hemolysis), which can produce symptoms including red or darkened urine and a low red blood cell count (anemia). PNH patients can also develop aplastic anemia, which is accompanied by a decreased platelet and/or white blood count in addition to anemia. Conversely, patients with aplastic anemia sometimes develop PNH. Patients are also at increased risk of developing blood clots, which cause symptoms such as severe leg, abdominal, or chest pain, shortness of breath, jaundice, or headache.
Physicians diagnose PNH using one of two blood tests — either a Ham test or flow cytometry. Treatments for PNH patients with hemolytic anemia include transfusion, folic acid, and if appropriate, iron supplements. Low red blood cell, platelet, and white cell counts can be treated with steroids or with the same immunosuppressive drugs used to treat aplastic anemia. Blood clots are usually treated with anticoagulants, and sometimes, if severe, with tissue plasminogen activator (TPA). PNH can be cured by bone marrow transplantation; this procedure should be considered on an individual basis, based on the patient’s age and symptoms.

TESTING FOR DIAGNOSIS OF PNH

Bone marrow samples can be obtained by aspiration and trephine biopsy. Sometimes, a bone marrow examination will include both an aspirate and a biopsy. The aspirate yields semi-liquid bone marrow, which can be examined by a pathologist under a light microscope as well as analyzed by flow cytometry, chromosome analysis, or polymerase chain reaction (PCR). Frequently, a trephine biopsy is also obtained, which yields a narrow, cylindrically shaped solid piece of bone marrow, 2mm wide and 2 cm long (80 μL), which is examined microscopically (sometimes with the aid of immunohistochemistry) for cellularity and infiltrative processes. An aspiration, using a 20 mL syringe, yields approximately 300 μL of bone marrow.[1] A volume greater than 300 μL is not recommended, since it may dilute the sample with peripheral blood.[1]



In a bone marrow analysis detection of the red cells will produce a defective protective layer. The white cell and platelets will be lower than normal . This result will decrease immunity in the body and therefore decrease resistance against disease. 

The Ham Test is also used in the diagnosis of PNH. 
HAM test is used to evaluate patients with suspected PNH (Paroxysmal Noctural Hemoglobinuria) or suspected congential dyserythropoietic anemia, especially with hemosiderinuria, Pancytopenia, decreased RBC acetyl cholinesterase, decreased leukocyte alkaline phosphatase, negative direct Coomb’s test, and/or apparent marrow failure.
Patients red cells show a high sensitivity to complement mediated hemolysis .

 LDH ( lactate dehydrgenase) is a blood test that is used to monitor tissue damage. The most important measure of hemolysis — can help provide a more complete clinical picture of PNH when performed in conjunction with other laboratory tests and patient-reported assessments. Monitoring of hemolysis in patients with PNH can be done by measuring LDH levels. LDH levels in PNH can be frequently elevated, in some cases exceeding 20 times the upper limit of normal during severe exacerbations.3 It is important to establish a baseline LDH level and continue monitoring over time. Static or “snapshot” measurements of LDH may not reflect the chronic and progressive course of the disease.








TREATMENT

Some of the supportive therapies that are currently being used to help ease the symptoms of PNH include transfusions and anticoagulants (Blood thinners)
Transfusions are recommended during times of severe haemoglobin depletion when your body cannot generate enough new cells to make up for those lost to haemolysis. It may be used on a periodic basis when your haemoglobin level is steadily decreasing.
Your physician may prescribe anticoagulants to you, in order to either reduce the risk of getting blood clots or may need to dissolve a clot when it happens.

Complement Inhibition:

When unregulated, the complement can lead to various severe diseases causing damages in multiple organs. Complement inhibitors are compounds which bind to enzymes in the complement system. Their role is to suppress or reduce the activity of complement.

Bone Marrow Transplantation:

Bone marrow transplantation (BMT) is the only known treatment that may cure PNH. It involves replacing the body’s defective blood stem cells by new healthy ones from a donor. However, bone marrow transplantations carry significant risks which should be discussed with your doctor.
It is important to remember that symptoms of PNH may vary from patient to patient, and a plan to manage your PNH may work for you but may not work for someone else. This is why it is so important to discuss treatment options with your doctor.


 The following websites are helpful.

http://www.pnhsource.eu/Diagnosing%20PNH/Flow%20Cytometry/Default.aspxhttp://www.mskcc.org/cancer-care/adult/rare-hematologic-disorders/paroxysmal-nocturnal-hemoglobinuria
http://www.medindia.net/bloodtest/hematology/pnh_test.htmhttp://pnhsource.eu/Treatment%20Options/Default.aspx

Friday, December 2, 2011

Blood Disorders: Polycythemia Vera

Polycythemia vera is not a cancer,but is a disease of the bone marrow.  Hematology oncologists handle the diagnosis and treatment of this disease. The bone marrow makes too many red cells.  Polycythemia is rare and develops slowly.  The problem of elevated red blood cells is usually found in a routine complete blood count which is ordered by doctor.   The image below shows what polycythemia vera looks like under the microscope.



If  polycythemia vera is not treated then it could become life threatening. The symptoms are the following:
In its early stages, polycythemia vera usually doesn't cause any signs or symptoms. However, as the disease progresses, you may experience:
  • Headache
  • Dizziness
  • Itchiness, especially following a warm bath or shower
  • Redness of your skin
  • Shortness of breath
  • Breathing difficulty when you lie down
  • Numbness, tingling, burning or weakness in your hands, feet, arms or legs
  • A feeling of fullness or bloating in your left upper abdomen due to an enlarged spleen
  • Fatigue  
Blood tests
Doctors most frequently use blood tests to diagnose polycythemia vera. If you have polycythemia vera, blood tests may reveal:
  • An increase in the number of red blood cells and, in some cases, an increase in platelets or white blood cells.
  • Elevated hematocrit measurement, the percentage of red blood cells that make up total blood volume.
  • Elevated levels of hemoglobin, the iron-rich protein in red blood cells that carries oxygen.
  • Very low levels of erythropoietin (EPO), a hormone that stimulates bone marrow to produce new red blood cells.
Bone marrow aspiration or biopsy
If your doctor suspects you have polycythemia vera, he or she may recommend a bone marrow aspiration or biopsy to collect a sample of your bone marrow. A bone marrow biopsy involves taking a sample of solid bone marrow material. A bone marrow aspiration is usually done at the same time as a biopsy. During an aspiration, your doctor withdraws a sample of the liquid portion of your marrow.
If an examination of your bone marrow shows that it's producing higher than normal numbers of blood cells, it may be a sign of polycythemia vera.
Tests for the gene mutation that causes polycythemia vera
If you have polycythemia vera, analysis of your bone marrow or blood also may show the mutation in the cells (JAK2 V617F mutation) that's associated with the disease.
n a bone marrow aspiration and biopsy, a doctor or nurse uses a thin needle to remove a small amount of liquid bone marrow, usually from a spot in the back of your hipbone called the posterior iliac crest. A bone marrow biopsy is often taken at the same time. This second procedure removes a small piece of bone tissue and the enclosed marrow.

Treatment of polycythemia include doing a phlebotomy to remove blood that is putting your circulatory system in overload.  It is similar to giving blood to the Red Cross.  Drugs are given if the phlebotomy is not enough to relieve the increased red cell production.  
 Hydroxyurea (Droxia, Hydrea) or anagrelide (Agrylin), to suppress your bone marrow's ability to produce blood cells may be used. Interferon-alpha may be used to stimulate your immune system to fight the overproduction of red blood cells.
Any abnormal symptoms should always be addressed by a doctor.  Be in tune with your body and document changes to help the doctor to have a clearer picture of your health problems.

You can get more information be searching https:www.mayoclinic.com