This book describes Essential Thrombocytosis, Diagnosis and Treatment and Related Diseases
Essential thrombocytosis (ET) is a medical disorder in which the bone marrow produces too many platelets.
Platelets are a part of the blood that helps in blood clotting.
Thrombocytosis is measured as a platelet count above the upper limit of the normal range (450 x 109/L in adults)
It is essential to differentiate between true hematological disease causing primary thrombocytosis and secondary or reactive thrombocytosis produced by an overstated physiological response to a primary disorder.
Primary or essential thrombocytosis is a chronic myeloproliferative disorder (produced by bone marrow).
Causes
Essential thrombocytosis happens from an overproduction of platelets.
Untreated, ET becomes worse over time.
Since these platelets do not work normally, blood clots and bleeding are frequent disorders.
ET is part of a group of disorders known as myeloproliferative disorders.
Others are:
1. Chronic myelogenous leukemia (cancer that starts in the bone marrow)
2. Polycythemia vera (bone marrow disease leading to a rise in the number of blood cells)
3. Primary myelofibrosis (bone marrow disorder where fibrous scar tissue replaced the marrow)
Many people with ET have a mutation of a gene (JAK2, CALR, or MPL).
Essential thrombocytosis is most frequent in middle aged people.
It can also be observed in younger people, particularly women under age 40.
Symptoms
Frequent symptoms of blood clots may be:
1. Headache (most frequent)
2. Tingling, coldness, or blueness in the hands and feet
3. Feeling dizzy or lightheaded
4. Vision problems
5. Mini-strokes (transient ischemic attacks) or stroke
If bleeding is a difficulty, symptoms may be:
1. Easy bruising and nosebleeds
2. Bleeding from the gastrointestinal tract, respiratory system, urinary tract, or skin
3. Bleeding from the gums
4. Prolonged bleeding from surgical procedures or tooth removal
Diagnosis
Most of the time, Essential thrombocytosis is found through blood tests done for other health complaints before symptoms occur.
The doctor may detect an enlarged liver or spleen on physical examination.
The patient may also have abnormal blood flow in the toes or feet that produces skin injuries in these areas.
Other tests may be:
1. Bone marrow biopsy
2. Full blood count (FBC)
3. Genetic tests (to look for a change in the JAK2, CALR, or MPL gene)
Treatment
The treatment requires an evaluation of the patient's risk and where possible taking remedial action.
Patients with essential thrombocythemia are regarded as having high risk of:
1. Thrombosis if they are older than 60 years or have a previous history of thrombosis
2. Bleeding if platelet counts are above 1,500 x 109/L.
Patients with low-risk essential thrombocythemia are normally treated with low-dose aspirin,
The treatment of high-risk essential thrombocythemia is based on the use of cytoreductive therapy
Hydroxyurea is the drug of choice and interferon alfa (IFN-α) is reserved for young patients or pregnant women
In patients with low risk, simple observation may be acceptable.
They are likely not to have a high risk of complications of surgery or pregnancy.
Where there are symptoms of micro-vascular occlusion such as erythromelalgia, low-dose aspirin may be very effective.
In high-risk patients, with very high platelet counts, the platelets must be decreased.
Possible treatments are hydroxyurea, anagrelide or IFN-α.
When there are acute complications, platelet-pheresis may attain a rapid drop in platelet count.
If patients need elective surgery cyto-reductive therapy should be used to decrease the risk of both thrombosis and hemorrhage
TABLE OF CONTENT
Introduction
Chapter 1 Essential Thrombocytosis
Chapter 2 Causes
Chapter 3 Symptoms
Chapter 4 Diagnosis
Chapter 5 Treatment
Chapter 6 Prognosis
Chapter 7 Low Platelets
Chapter 8 High Platelets
Epilogue
