2023-10-05 09:33:01
Platelets, also called thrombocytes, are cellular elements of the blood that originate in the bone marrow and whose function is to produce clots that prevent bleeding. A very low level of platelets, less than 100,000 per cubic millimeter, can be the cause of primary immune thrombocytopenia, a rare disease that affects children and adults.
This disease does not have a genetic basis, it is an autoimmune pathology “caused by the deregulation of the immune system by producing uncontrolled antibodies that break down platelets,” explains EFEsalud. hematologist Cristina Pascual, president of the Spanish Group on Immune Thrombocytopenia (GEPTI) of the Spanish Society of Hematology and Hemotherapy (SEHH).
The most common symptoms are the appearance of spontaneous bruises anywhere on the body, subcutaneous bleeding points, gum or nose bleeding, heavy menstrual bleeding or hemorrhages, such as brain hemorrhages, in severe cases, although the most common is fatigue that can lead to depression and anxiety.
An adjusted platelet level ranges from 150,000 to 400,000 per cubic millimeter. A condition for thrombocytopenia is having fewer than 100,000 thrombocytes.
“Below 30,000/20,000 platelets per cubic millimeter the risk of bleeding increases. But there is a lot of variability between patients, not all bleed with the same intensity,” points out the section head at the Hematology Service of the Gregorio Marañón General University Hospital in Madrid.
A heterogeneity that, in part, may depend on factors such as whether the patient is on anticoagulant treatment, “but there is variability that we do not know… Why do two patients of the same age, sex… one bleed and the other not?” ask.
Infographic provided by the Spanish Immune Thrombocytopenia Group.
Low platelets are not always a disease
Having low platelets, between 100,000 and 150,000 per cubic millimeter, in most cases does not cause illness, the doctor points out.
One of these causes may be hereditary thrombocytopeniawith first-degree relatives also with low platelets that are detected in a routine blood test, and which allows a differential diagnosis to be made with immune thrombocytopenia.
“We have made a lot of progress in recent years because genetic mutations can be detected and a molecular diagnosis can be given,” says the specialist.
Immune thrombocytopenia, a rare disease with the challenge of diagnosis
The incidence of primary immune thrombocytopenia It is 2 to 4 cases per 100,000 inhabitants, which is why it is considered a rare or low-prevalence disease.
According to Dr. Cristina Pascual, the diagnosis of primary immune thrombocytopenia continues to be a challenge due to the lack of a specific biomarker, which is why it is considered a “diagnosis of exclusion”, that is, it is reached after ruling out other diseases that produce low platelets.
It can occur from acute form when symptoms appear suddenly and resolve on their own, although sometimes they need treatment.
This variety usually occurs in children whose episodes of thrombopenia are cured without treatment, but if they needed it it would be the same as in the first line for adults, corticosteroids, but less prolonged in time as they are more vulnerable to side effects.
The chronic form affects 4 out of 10 patients adults. A characteristic profile is that of men and women over 65 years of age who need precise control in adjusting the level of platelets since many are medicated with anticoagulants, are usually polymedicated and have vascular risk factors.
“The risk of bleeding increases in these patients and their platelet level generally has to exceed 50,000,” says the professor at the Faculty of Medicine of the Complutense University of Madrid.
Another profile is that of young women at risk of heavy menstrual bleeding and monitoring in case of pregnancy to avoid complications.
The treatments
Los corticosteroids They remain the first-line treatment, although they are no longer prescribed for more than eight weeks.
If they do not respond, the next step is drugs thrombopoietin receptor analogues that, since they came into clinical practice about ten years ago, “they have changed the course of the disease and the quality of life of the patients,” points out the hematologist.
Hematologist Cristina Pascual, president of the Spanish Immune Thrombocytopenia Group of the SEHH. Photo provided
A third line, although it is limited to recurrent patients and is not usually practiced, is spleen removalwhich is the organ where the antibodies, produced by B lymphocytes, destroy the most platelets.
This surgery, before the arrival of thrombopoietin receptor analogue drugs, was the technique that allowed the disease to be kept in remission for longer since none of the treatments are curative.
Now research into new drugs is in full development with inhibitors or monoclonal antibodies against a target, BAFF, to reduce the production and therefore the action of antibodies that attack platelets.
Research that has also been promoted, since 2014, by the Spanish Immune Thrombocytopenia Group of the IT’S OKAY which also ensures the training of professionals and pursues the objective of improving the diagnosis, treatments and quality of life of patients.
Pay attention to high platelets
On the other hand, having platelets above 400,000 per square millimeter means ruling out suffering from the so-called thrombocytosis and its signs, such as low iron (iron deficiency), an infection or some type of inflammation. When the underlying disease is cured, platelets return to their normal parameters.
If they do not stabilize, concludes Dr. Cristina Pascual, it is necessary to try to rule out a myeloproliferative syndromeblood cancer caused by the uncontrolled growth of platelets clonally.
#platelets