Schistocytes: Definition, Causes, Symptoms, Diagnosis and Treatment

They are fragments of erythrocytes of small and irregular shape.

Since these cells are produced due to the breakdown of red blood cells, the schistocyte is about half the size of normal erythrocytes and may have a deeper red appearance.

According to laboratory policy, the presence of these red blood cell fragments in a peripheral blood smear is a hematologic emergency that requires prompt review and investigation.

Schistocytes are sometimes called ‘ helmet cells. ‘ Schistocytes, or fragments of erythrocytes, are found in many blood diseases. They are smaller than normal red blood cells and are variable in shape.

Sometimes they have sharp angles or spines (spurs), irregular and asymmetrical, and sometimes they are round in outline, usually deeply stained but occasionally pale due to loss of hemoglobin at the time of fragmentation.

If they are round and densely stained, they may be called microspherocytes. A true schistocyte does not have central pallor.

It is essential to know about schistocytes as a characteristic of megaloblastic and dyserythropoietic anemias, thus avoiding the erroneous attribution to thrombotic microangiopathy.

 

The schistocytes are often rounded in burns, either microspherocytes or tiny disc-shaped fragments.

In addition, it can be seen that the erythrocytes are sprouting from small rounded blisters of cytoplasm.

It is not uncommon that, as in hemolytic uremic syndrome in children, the blood picture becomes more bizarre due to the overlap of varying degrees of pinocytic change.

Schistocytes are fragments of red blood cells formed by the fragmentation of abnormal cells, for example, in pyropoikilocytosis associated with some genetic defect or mechanical injury, toxin, or heat-induced change of pre-normal cells.

As a result of mechanical damage, schistocytes often coexist with keratocytes.

Causes of schistocytes

Several microangiopathic diseases, such as disseminated intravascular coagulation and thrombotic microangiopathies, generate fibrin chains that cut red blood cells as they try to pass a thrombus, creating schistocytes.

Schistocytes are often seen in patients with hemolytic anemia. Red blood cell fragmentation occurs due to mechanical damage to the circulation.

They are often a consequence of mechanical heart valve prostheses and can also be seen in patients on dialysis.

In addition, schistocytes occur in abnormalities of the red blood cells of the cytoskeleton, such as acquired and inherited disorders of the red blood cells in association with marked anisopoikilocytosis.

Excessive schistocytes in the blood can signify microangiopathic hemolytic anemia, where the most common cause is aortic stenosis.

An increase in schistocytes can be observed in hemolytic anemia associated with burns and prosthetic implants and the rejection of kidney transplants.

Schistocytes present with microenteropathic hemolytic anemia and are associated with various noninfectious diseases, mainly disseminated intravascular coagulation.

Schistocytes are present in disseminated intravascular coagulation either caused by a noninfectious disorder, such as a malignant tumor, or an underlying infectious disease, e.g., meningococcemia.

Schistocytes are characteristic of gas gangrene but can also be found in other diseases, such as autoimmune hemolytic anemia, cirrhosis, transfusion reactions, and severe burns.

Symptoms

It is physically challenging to assess the symptoms associated with schistocytes because they could result from any hemolytic disease or kidney disease.

It can only be confirmed by differential cell count or morphological evaluation of the blood.

Many doctors recommend routine blood tests 2 to 3 times a year to rule out hemolytic disease.

Diagnosis

Schistocytes are generally obtained from direct physical damage to red blood cells secondary to vascular abnormalities or turbulent blood flow.

The shape of the fragments can vary from sharp or spiculated triangular.

Microangiopathic granulation has been reported in several disorders, including disseminated intravascular coagulation, glomerulonephritis, Hemangio’s sarcoma, myelphlebrosis, dyserythropoietic, and chronic toxic inoculation with doxorubicin.

Schistocytes have also been identified as a standard feature of disseminated intravascular coagulation.

A liver function test, kidney function test, and an ultrasound of the abdomen can confirm the diagnosis.

Also, your echocardiogram can be done.

Treatment of schistocytes

Treatment should be focused on the disease that, according to the differential diagnosis, causes the formation of schistocytes.