Hemolytic anemia (haemolytic anemia) is a group of blood diseases, or actually one of its components - red blood cells. In the course of haemolytic anemia, they are destroyed too quickly, and the cause can be both defects in the structure of red blood cells and diseases of other organs. Hemolytic anemia, apart from the symptoms typical of all types of anemia, such as fatigue and shortness of breath, has several characteristic symptoms. It is worth finding out when you can suspect this disease and what are its symptoms.

Hemolytic anemia( hemolytic anemia ) is a decrease:

  • hemoglobin levels (in HGB or HB laboratory test results below 14 g / dl for men and 12 g / dl for women)
  • hematocrit (HCT or HT less than 40% in men and 37% in women)
  • erythrocytes - red blood cells (RBC less than 4.2 million / μl in men and 3.5 million / μl in women)

by destroying circulating red blood cells in a process called hemolysis.

Hemolytic anemia: symptoms

When do symptoms appear?

If this disease is congenital, symptoms will appear at an early age, even in young children. However, if haemolytic anemia is acquired, symptoms will appear in adults, most often after diagnosis of a disease in which haemolysis occurs (e.g. after diagnosis of systemic lupus), very rarely it may be the first symptom of another disease.

What is the severity of symptoms?

If the hemolysis is minor and lasts a long time, the disease may not cause any discomfort. However, if there is a sudden drop in red blood cells, symptoms will begin fairly quickly, and if the drop is large, it can be life-threatening.

What symptoms may appear?

Any anemia, regardless of the cause, can lead to symptoms such as:

  • weakness
  • easy fatigue
  • concentration and attention disorders
  • headaches and dizziness

and less common ailments:

  • faster heartbeat
  • shortness of breath

In the case of haemolysis, we usually also deal with jaundice, which is the resulterythrocytes are destroyed too quickly in relation to the possibility of their metabolism, in addition, spleen enlargement and liver enlargement can occur.

Sometimes people suffering from hemolytic anemia also have gallstones, because the component of bile, bilirubin, is also a product of erythrocyte metabolism, if there is too much of this compound, it precipitates in the form of stones.

The remaining symptoms are specific to individual disease entities and result from the mechanisms that cause anemia described above:

  • Congenital spherocytosis is characterized by abnormal bone growth, gallbladder stones, and hemolytic crises. The latter are life-threatening conditions in which there is, inter alia, weakness, nausea, fever, abdominal pain, increased heart rate and acute renal failure
  • erythrocyte enzyme deficiencies are characterized by: jaundice, dark urine, and abdominal pain, occurring from certain medications, stress and infections
  • methemoglobinemia (one of the defects of hemoglobin), in turn, is a change in the valence of iron present in erythrocytes, so it cannot bind and carry oxygen. A characteristic symptom is cyanosis, most visible around the mouth or earlobe
  • sickle cell anemia, manifested by jaundice, gallstones, growth retardation, enlarged heart, vascular obstruction that causes organ ischemia

In the case of autoimmune diseases and lymphomas, their symptoms dominate, and the symptoms of anemia in these cases may include:

  • pain when swallowing
  • back pain
  • stomach ache
  • fever
  • red urine
  • and if hemolysis occurs in small vessels, it results in clots.

The spectrum of symptoms is therefore very large, and it should be remembered that hemolytic anemia has various complications.

Hemolytic anemia: complications

The effects of this disease can be many, starting with the least serious:

  • gall bladder stones
  • folate deficiency
  • skin ulcers
  • venous thromboembolism
  • aplastic and hemolytic breakthrough, associated with a sudden large drop in blood cells and posing a direct threat to life.

Hemolytic anemia: causes

Hemolytic anemia is a group of many diseases, their causes may vary, but the result is always the destruction of red blood cells.

Under normal conditionsThe red blood cell lives for about 120 days, then it is taken up by the spleen and broken down there, and the iron is stored from it.

As a result of defects in the erythrocytes themselves or in other organs such as the liver and spleen, this process occurs faster, even after 50 days.

Additionally, with increased haemolysis, the bone marrow cannot keep up with the production of new and replenishing blood cells, which results in a reduction in the number of erythrocytes.

Increased destruction of blood cells also puts too much strain on enzymes responsible for their metabolism, the process becomes ineffective and metabolites of blood cells remain in the circulation.

Red blood cell deficiency is characteristic of all anemia (e.g. iron deficiency anemia or vitamin B12 deficiency anemia) and therefore some symptoms are common and occur with all types of anemia.

The intensification of processes related to the decomposition and the presence of red blood cells in the circulation give the symptoms characteristic of hemolytic anemia.

Hemolytic anemia: types

Haemolytic anemia may be the result of a genetic mutation, then we call them congenital or acquired, e.g. in autoimmune diseases. The first of them are caused by damage to the blood cell itself and they are:

  • defects of the erythrocyte cell membrane - blood cells then have a changed shape, e.g. ovalocytosis, or the most common hereditary hemolytic anemia - spherocytosis (spherical shape of the blood cell)
  • defects of erythrocyte enzymes, so-called enzymopathies - the cytoplasm of erythrocytes contains a number of enzymes necessary for their functioning, haemolytic anemia may be the result of a deficiency of two enzymes: glucose-6-phosphate dehydrogenase and pyruvate kinase, they significantly contribute to energy production in erythrocyte
  • defects of hemoglobin, i.e. oxygen-carrying compound, these are hemoglobinopathies - sickle cell anemia and methaemoglobinaemia, in these diseases the ability of blood cells to carry oxygen is reduced and their shape may be changed, which makes them more prone to damage
  • insufficient formation of hemoglobin - thalassemia

In the case of acquired anemia, erythrocytes are normal, but they are destroyed by external factors.

One of the mechanisms is immunological processes, which lead to the production of antibodies against red blood cells.

These can be produced in the course of many diseases: autoimmune (e.g. systemic lupus), chronic lymphocytic leukemia, lymphomas, after certain medications, after organ transplants, blood transfusions and in the so-calledcold agglutinin disease and paroxysmal cold hemoglobinuria.

Another mechanism of extracellular destruction of erythrocytes is haemolytic microangiopathic anemia. Quite a complicated name, what does it mean?

Blood cells are destroyed for various reasons in small arterioles and veins, such as thrombotic thrombocytopenic purpura, hemolytic uremic syndrome or infections.

Interestingly, this is also the mechanism of action of some poisons, e.g. the venom of some spiders or vipers. Very rarely, haemolysis occurs as a result of mechanical damage to erythrocytes, e.g. after implantation of an artificial heart valve.

Hemolytic anemia: test results

The basic test to be performed when anemia (not only hemolytic anemia) is suspected is the complete blood count.

Anemia is indicated by a drop in the number of red blood cells, i.e. RBCs, below normal.

Based on other parameters, we can assess whether the blood cells present in the circulation have the right volume (MCV), the right amount of hemoglobin (MCH) and its concentration in the blood cell (MCHC), these are extremely important parameters that tell a lot about the cause decrease in the number of red blood cells.

In the case of haemolysis, the erythrocyte structure parameters are usually within the normal range, so we are dealing with the so-called normocytic anemia, normochromic anemia, i.e. erythrocytes have the right size, proper content and concentration of hemoglobin.

This indirectly means that the production process is undisturbed and the body has all the necessary substrates for its production.

Only in the case of thalassemia, in which the production process is disrupted, erythrocytes are smaller and have a lower hemoglobin content.

Another important parameter that can be found in the blood count are reticulocytes, labeled "Ret.". Reticulocytes are young erythrocytes that have recently left the bone marrow, and their increased number indicates intensive formation of new blood cells in the bone marrow.

This increase in production and the increase in reticulocytes is a response to insufficient number of functional red blood cells.

More advanced tests allow the detection of rare but characteristic shapes of erythrocytes, e.g. echinocytes (protruding erythrocytes) in enzymatic defects, thyroid erythrocytes in thalassemia, schistocytes (fragments of erythrocytes) in microangiopathic anemia, and also present in erythrocytes : Heinz bodies in methemoglobinemia or Howel-Jolly bodies in sickle cell anemia.

Research on red blood cells has been done in detaildescribed in the article on erythrocytes. Blood analyzes may also show deviations in the following range:

  • increase in LDH (lactate dehydrogenase, i.e. an enzyme present in erythrocytes), it is released when the erythrocyte is destroyed, hence its increased concentration in the blood during hemolysis
  • decrease in haptoglobin (free hemoglobin binding protein) its decrease is due to the fact that laboratory methods assess the amount of haptoglobin capable of binding hemoglobin, if this compound is released from damaged erythrocytes, the available haptoglobin particles bind to it and are "invisible" during the laboratory determination
  • increase in bilirubin, which is the end product of hemoglobin breakdown.

The urine test shows: urobilinogen and hemoglobinuria, i.e. the excretion of an increased amount of urobilin and hemoglobin in the urine.

These compounds are removed if the hemolysis is so severe that the liver is unable to efficiently metabolize the damaged blood cells.

Individual forms of haemolytic anemia have specific tests, but they are rarely performed and only in specialized centers, these include:

  • decreased activity of glucose-6-phosphate dehydrogenase
  • pyruvate kinase deficiency
  • increase in metHb (methemoglobinemia)
  • increase in HbS and HbF (sickle cell anemia)
  • and the more common direct Coombs test (it is performed in autoimmune diseases, not only those related to hemolysis, but in this case it facilitates the diagnosis of secondary anemia).

Sometimes, especially when the diagnosis is uncertain, a bone marrow biopsy is performed, which shows an increased formation of new red blood cells.

Treatment of hemolytic anemia

The treatment of diseases of the blood and hematopoietic system is done by a hematologist, although the basic diagnostics can also be performed by a family doctor.

Despite the variety of causes of hemolysis, the principles of treatment are similar.

In patients with such a diagnosis, first of all, it is necessary to maintain a sufficient number of red blood cells in the circulation, so sometimes it is necessary to transfuse their concentrates.

However, you must always provide the ingredients needed to create new red blood cells, i.e. folic acid and iron, if there is too little of it.

Before anemia treatment is started, it is necessary to exclude the secondary nature of this disease, i.e. treat diseases that may cause haemolytic anemia, and discontinue drugs that may cause it.

A common method of treatment for a fewanemia: spherocytosis, thalassemia, enzyme disorders is also its last line - surgical removal of the spleen.

This organ catches and destroys distorted erythrocytes, but if there are too many of them, the action of the spleen causes severe anemia.

Removal of this organ is to keep the circulation of abnormal but partially fulfilling blood cells in the circulation.

Before splenectomy is performed, an attempt is made to treat hemolysis specifically to the causative agent:

  • in autoimmune diseases, glucocorticosteroids, immunosuppressive therapy, and plasmapheresis (a procedure that allows you to remove all antibodies from the blood, including anti-erythrocytes) are used
  • in methemoglobinemia, you can administer methylene blue, use a hyperbaric oxygen chamber, and use exchangeable blood transfusions. In light, chronic cases - ascorbic acid and riboflavin
  • vitamin C and zinc are given in thalassemia
  • in sickle cell anemia - hydroxycarbamide, pain relievers and anticoagulants

The basis of hemolytic anemia is very diverse, as well as the mechanism by which blood cell damage occurs, but they are a common group of diseases, because the end result is always the same - destruction of a young, functional erythrocyte.

This, in turn, has numerous consequences, primarily blood does not supply cells with the amount of oxygen they need to function properly, and the effects can range from fatigue and faster heartbeat to a heart attack.

If haemolytic anemia is suspected, the basic diagnosis should be made at the family doctor, however, the haematologist decides about more advanced tests and treatment.

Category:

Cardiology