Polycythemia vera
The content of the article:
- Causes and risk factors
- Forms of the disease
- Disease stages
- Symptoms
- Diagnostics
- Treatment
- Possible complications and consequences
- Forecast
- Prevention
Polycythemia vera (polycythemia primary, Vakez's disease, erythremia) is the most common disease of the group of chronic myeloproliferative diseases. The pathological process mainly affects the erythroblastic bone marrow growth, which causes an increase in the number of red blood cells in the peripheral blood, as well as an increase in the viscosity and mass of circulating blood (hypervolemia).
With polycythemia vera, the number of erythrocytes in the peripheral blood increases
The disease occurs mainly in the elderly (the average age of onset is about 60 years), but is also diagnosed in young people and children. Younger patients are characterized by a more severe course of the disease. Men are slightly more susceptible to polycythemia vera than women, but young patients are inversely proportional.
Causes and risk factors
The reasons contributing to the occurrence of polycythemia vera have not been definitively established. Pathology can be both hereditary and acquired. Discovered a family predisposition to the disease. In patients with polycythemia vera, gene mutations are identified that are inherited in an autosomal recessive manner.
Risk factors include:
- the effect on the body of toxic substances;
- ionizing radiation;
- X-ray irradiation;
- extensive burns;
- long-term use of a number of medicines (gold salts, etc.);
- advanced forms of tuberculosis;
- distress;
- viral diseases;
- tumor neoplasms;
- smoking;
- endocrine disorders caused by adrenal tumors;
- heart defects;
- liver and / or kidney disease;
- extensive surgical interventions.
Forms of the disease
Polycythemia vera is of two types:
- primary (not a consequence of other pathologies);
- secondary (develops against the background of other diseases).
Disease stages
In the clinical picture of polycythemia vera, three stages are distinguished:
- Initial (oligosymptomatic) - clinical manifestations are insignificant, duration is about 5 years.
- The erythremic (expanded) stage lasting 10–20 years, in turn, is divided into substages: IIA - myeloid metaplasia of the spleen is absent; IIB - the presence of myeloid metaplasia of the spleen;
- Stage of post-erythremic myeloid metaplasia (anemic) with or without myelofibrosis; capable of turning into chronic or acute leukemia.
Symptoms
Polycythemia vera is characterized by a prolonged asymptomatic course. The clinical picture is associated with an increased production of erythrocytes in the bone marrow, which is often accompanied by an increase in the number of other cellular elements of the blood. An increase in platelet counts leads to vascular thrombosis, which can cause strokes, myocardial infarction, transient ischemic attacks, etc.
Polycythemia vera is characterized by pruritus, aggravated by water
In the later stages of the disease, there may be:
- itchy skin, aggravated by water;
- attacks of pressing pain behind the sternum during physical exertion;
- weakness, increased fatigue;
- memory disorder;
- headaches, dizziness;
- erythrocyanosis;
- redness of the eyes;
- visual impairment;
- increased blood pressure;
- spontaneous bleeding, ecchymosis, gastrointestinal bleeding;
- dilated veins (especially veins in the neck);
- short-term intense pain in the fingertips;
- stomach and / or duodenal ulcer;
- joint pain;
- heart failure.
Diagnostics
The diagnosis of polycythemia vera is established on the basis of the data obtained during the examination:
- collection of anamnesis;
- objective examination;
- general and biochemical blood test;
- general urine analysis;
- trepanobiopsy followed by histological analysis of the biopsy;
- ultrasound examination;
- computed or magnetic resonance imaging;
- molecular genetic analysis.
Blood test for polycythemia vera shows an increase in the number of red blood cells
Diagnostic criteria for polycythemia vera:
- increased indicators of the mass of circulating erythrocytes: in men - more than 36 ml / kg, in women - more than 32 ml / kg;
- leukocytes - 12 × 10 9 / l and more;
- platelets - 400 × 10 9 / l and more;
- increase in hemoglobin up to 180–240 g / l;
- an increase in oxygen saturation in arterial blood - 92% or more;
- an increase in the serum content of vitamin B 12 - 900 pg / ml or more;
- increased activity of alkaline phosphatase of leukocytes up to 100;
- splenomegaly.
Differential diagnosis is required with absolute and relative (false) erythrocytosis, neoplasms, hepatic vein thrombosis.
Treatment
Treatment of polycythemia vera is primarily aimed at preventing the development of leukemia, as well as prevention and / or therapy of thrombohemorrhagic complications. Symptomatic therapy is carried out to improve the patient's quality of life.
To reduce blood viscosity in hyperviscosity syndrome, a course of phlebotomies (exfusion, bloodletting) is performed. However, with an initially high thrombocytosis, phlebotomy can contribute to the occurrence of thrombotic complications. Patients who do not tolerate bloodletting well, as well as in childhood and adolescence, are shown myelosuppressive therapy.
Phlebotomy for polycythemia vera reduces blood viscosity
Interferon preparations are prescribed for a long course (2-3 months) to reduce myeloproliferation, thrombocythemia, and also to prevent the development of vascular complications.
With the help of hardware therapy methods (erythrocytapheresis, etc.), excess cellular elements of the blood are removed. In order to prevent thrombosis, anticoagulants are prescribed. To reduce the manifestations of itching, antihistamines are used. In addition, patients are advised to adhere to a dairy-plant diet and limit physical activity.
With a pronounced increase in the size of the spleen (hypersplenism), patients are shown splenectomy.
Possible complications and consequences
Polycythemia vera can be complicated by:
- myelofibrosis;
- spleen infarction;
- anemias;
- nephrosclerosis;
- gallstone and / or urolithiasis;
- gout;
- myocardial infarction;
- ischemic stroke;
- cirrhosis of the liver;
- pulmonary embolism;
- acute or chronic leukemia.
Forecast
With timely diagnosis and treatment, the survival rate exceeds 10 years. Without adequate therapy, 50% of patients die within 1-1.5 years from the moment of diagnosis.
Prevention
Due to the fact that the exact causes of the disease are unclear, effective methods of preventing polycythemia vera have not yet been developed.
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Anna Aksenova Medical journalist About the author
Education: 2004-2007 "First Kiev Medical College" specialty "Laboratory Diagnostics".
The information is generalized and provided for informational purposes only. At the first sign of illness, see your doctor. Self-medication is hazardous to health!
