ESSENTIAL THROMBOCYTHEMIA(TE)

La Thrombocytemie Essentielle

 

icn_gene   General : 

Literally: Thrombocythemia = causes thrombosis

Essential = Which has no known cause.

Impact: Approximately ten cases per 1 million persons. Feminine ascendancy.

Classified as a rare disease.

We all have read or heard that ET is a disease associated with elderly people. This assertion is seriously questionable given new research and information over the years. This error of assessment is based on two reasons:

  1. The chronic nature of the disease results in a cumulative effect. Any young patient will become old one day. In the age curve, We attend only a progress of the disease ,not the number of instances.
  2. Since 2000, up until the present day, the number of diagnoses has increased steadily, mainly due to progress of CBCs (Complete Blood Count). But we cannot say for a person who is diagnosed and is over 60 years old, how long the disease has been present (10, 20, 30 years).

icn_sym   Symptoms:

They are many symptoms, and often they are differents from one individual to another.

The most common symptom is being unusually tired, which can occur either continuously or sporadically.

A TIA (Temporary ischemic accident) occurs when there is a temporary blockage of a vessel by a strand of aggregated platelets. TIA often affects vision (ophthalmic artery); fingers (sensation of numbness in the finger); or any other body part.

Pruritus (intense itching) is also A wide-spread effect.

The occurrence of major vascular events (stroke, heart attack, spleen, portal vein, or mesenteric infarction), which are fortunately increasingly rare, may occur for patients who have had the disease for a long time but have not being diagnosed or treated.

CBCs, performed for other reasons, are increasingly behind the discovery of the disease.

 

icn_diag   The diagnosis:

The diagnosis must always be done by a haematologist.

The first phase of diagnosis is always a blood count. Platelet counts above normal (400 x 10⁹) is a probable sign of a MPN (Myeloproliferative Neoplasms).

The search for a known mutation, JAK2 or CALR, can affirm, if the result is positive, the presence of a MPN. If no mutation is known, But there are still transfers which were not discovered yet

Following the differential diagnosis. If erythrocyte and leukocyte cell lines are normal; if no other signs are evident to identify other diseases, we can confirm that it is probably a ET.

A bone marrow examination may be necessary in some cases to confirm the diagnosis. Although unpleasant, this review also collects interesting data on the state of the marrow and its cells, the level of fibrosis, which may allow for comparison at a later stage.

A moderate splenomegaly (enlarged spleen: from 12 to 15 cm) is sometimes observed.

Sometimes ET is apparent at the first sign of another disease, such as Polycythemia Vera that will appear over the months in the CBCs.

ET is a chronicle disease that we do not know how to be at present cured; at present we can only limit the effects of the disease.

There seems to be a familial form of ET. We lack statistical data on this point; but they appear to be a very small minority (a few percent)

There also exists what is called reactive ET, which is caused by exposure to ionizing elements or aromatic hydrocarbons such as benzene vapors. These ETs do not differ from the primary ET either clinically or biologically, but they are reversible; it can however take several years before they disappear after the ending exposure to the elements.

Essential Thrombocythemia and Pregnancy:

In the vast majority of cases pregnancy is possible for women with Essential Thrombocythemia. One should take advice from a haematologist before trying to conceive, or arrange a consultation with a haematologist where conception has already occurred. The haematologist may change the treatment, but in all cases the pregnancy should be followed in consultation with and according to the obstetrician.

 

icn_trait   Treatments:

Any person with ET must meet regularly with a haematologist who will decide on the frequency of consultation according to the state of their patient; and prescribe appropriate treatment.

Hydroxyurea (Hydrea) at present is the standard treatment. Usually has good efficacy, its side effects are limited (see the product’s instructions or check the internet).

This product induces male sterility. It would be wise if you plan to take hydroxyurea to freeze sperm in anticipation of future fatherhood.

Pipobroman (Vercyte) and other alkylating(Myleran, P32) are now being prescribed less frequently, except for short periods and for elderly patients, because they can cause acute leukemia.

Anagrelide chloride (Xagrid) has the distinction of not acting at the level of stem cells but in differentiated cells, exclusively on the platelet lineage. Anagrelide is useful when there are fears of anaemia developing. People react different to Anagrelide.

Pegylated interferons (α2A or α2B) are widely prescribed. People react differently to them as they often result in extreme fatigue and pain (see instructions for side effects).

JAK2 inhibitors are currently undergoing numerous tests. It appears that some will be able to control the platelet count, however the fact remains that their safety is not fully known, and that clinical trials should verify the advantages they can bring compared to current treatments. The JAKAVI is still currently being tested for ET.

 

icn_prono   Prognosis:

It can be stated that currently an Essential Thrombocythemia carrier has a life expectancy comparable to that of the general population.

However, the disease may progress in two ways:

  1. Progresses into ‘Acute Myeloid Leukaemia’ AML (# 2%)
  2. Progresses into myelofibrosis, and possibly in the longer term to AML (# 5%). In this instance, ET frequently evolves into myelofibrosis within 10-20 years (median: 12 years)

 

icn_evol   Criteria of evolution:

  • Signs of anaemia, decreased hematocrite, and hemoglobine.
  • Worsening fatigue.
  • Pain on the side of the spleen gene (left chest under the heart).
  • The appearance of blasts in the blood count.
  • Fast and unexplained weight loss.
  • Severe night sweats

These signs should quickly prompt consultation with a haematologist.