Content :
◉ What is Spherocytosis?
Spherocytes, or Spherocytosis, are red blood cells that take on a round shape instead of the typical biconcave disc shape when observed under a microscope. They are less deformable and more fragile, which increases their susceptibility to destruction by the spleen.
In a peripheral blood smear, spherocytes have the following characteristics:
- Round shape.
- Smaller than a normal red blood cell.
- Darker (deeply staining red cell).
- Lack central pallor
The common cause of spherocyte formation is hereditary spherocytosis, a genetic disorder that affects red blood cells. However, it is not exclusive to this disease and can be observed in various other medical conditions.
◉ Associated Disease with Spherocytosis
Spherocytes can be observed in various other conditions. Some of the common causes includ:
- Hereditary spherocytosis.
- Hemolytic anemia (Autoimmune, Allo-Immune, MAHA, Drug-Induced, etc)
- ABO incompatibility.
- Sickle cell disease.
- Hypersplenism.
- Severe Burns (due to budding off of part of the damaged red cell).
- Rred blood cell storage lesion.
- Pyruvate kinase deficiency.
- Glucose-6-Phosphate (G6PD) Deficiency.
- Hereditary Elliptocytosis.
◉ CBC in case of Spherocytosis
Here are some variations in CBC parameters that may be associated with the presence of spherocytes:
- Mean Corpuscular Hemoglobin Concentration (MCHC): Normal or Increased
- Mean Corpuscular Hemoglobin (MCH) : Normal or Increased
- Mean Corpuscular Volume (MCV): Normal or Increased.
- Red Cell Distribution Width (RDW): generally increased.
- Reticulocyte count : Normal or Increased.
- Hemoglobin (Hb), Hematocrit (Hct): Normal or decreased.
◉ Possible confusion
There are instances where confusion can arise in the identification of spherocytes on a blood smear. Some examples include
- Microcytes (microcytosis): In cases where the blood smear is too thin, the characteristic central clearing (area of pallor) in normal red blood cells may not be clearly visible. This lack of central pallor can make microcytes, which are already smaller than normal cells, resemble spherocytes.
- Irregularly Contracted Red Cells (spur cells): These cells can be hyperchromatic and lack central pallor, but they have an irregular outline.
- Polychromatic erythrocyte (PCE).
◉ Conclusion
Spherocytes are abnormally shaped red blood cells that appear spherical instead of the typical biconcave disc shape.
While most commonly seen in hereditary spherocytosis, spherocytes formation can be associated with a variety of other conditions.
Further clinical and paraclinical exploration is necessary for the doctor to establish a precise diagnosis and determine adequate treatment.