Red Blood Cell Disorders
In 1658, the Dutch naturalist, Jan Swammerdam was the first person to observe red blood cells under the microscope, describing them as oval particles in frog blood. Yet the routine use of the microscope and methods to quantitate red blood cell counts, haemoglobin concentration, and the haematocrit did not see the light of day until late 1800s.
What is a red blood cell disorder?
Red blood cell disorders refer to conditions that affect either the number or function of red blood cells (RBCs). Also known as erythrocytes, red blood cells carrying oxygen throughout the body.
Types of red blood cell disorders
There are many different types of RBC disorders, including conditions that affect the production, components, and abilities of RBCs. Dysfunction of RBCs can lead to several issues in the body.
Some examples of RBC disorders include:
Hemoglobinopathies are disorders that involve the haemoglobin protein within RBCs. Haemoglobin is an iron-rich molecule responsible for the red colour of the cells. Hemoglobinopathies cause an abnormal production or change the structure of the haemoglobin. Examples of hemoglobinopathies include sickle cell anaemia and thalassemia.
Thalassemia is a condition that affects the body’s ability to produce haemoglobin and RBCs. As a result, this typically causes a person to have fewer healthy RBCs.
Sickle cell anaemia is a type of sickle cell disease. Sickle cell disease creates blood cells that are misshapen and die too early. This causes a shortage of RBCs (anaemia) that lead to other issues such as the cells having difficulty traveling through the blood vessels.
- Cytoskeletal abnormalities
Cytoskeletal abnormalities in RBCs include conditions that change the structure or porousness of the RBC or its membranes. Examples of cytoskeletal abnormalities include spherocytosis and elliptocytosis.
Spherocytosis is a condition that causes the body to produce abnormal RBCs that are rounder and more spherical than the healthy disc shape of a normal RBC. This makes the blood cells more fragile and prone to breaking. Spherocytosis is a type of haemolytic anaemia. It is hereditary, passed from a person to their child through genetic mutations.
Hereditary elliptocytosis, also known as ovalocytosis, is an inherited blood disorder in which an abnormally large number of the person’s red blood cells are elliptical rather than the typical disc shape.
RBC enzymopathies are genetic conditions that affect the production of enzymes in RBCs and cell metabolism. Examples of RBC disorders that involve enzyme deficiencies include glucose-6-phosphate dehydrogenase deficiency(G6PD) and pyruvate kinase deficiency.
G6PD deficiency is an inherited condition. It is when the body doesn’t have enough of an enzyme called G6PD (glucose-6-phosphate dehydrogenase). This enzyme helps red blood cells work properly. A lack of this enzyme can cause haemolytic anaemia. This is when the red blood cells break down faster than they are made.
Pyruvate kinase deficiency is an inherited lack of the enzyme pyruvate kinase, that is used by red blood cells. Without this enzyme, red blood cells break down prematurely, resulting in a low level of red blood cells. It is another type of haemolytic anaemia.
- Nutritional anaemias
Nutritional-deficiency anaemia is a common disease that happen if the body does not absorb enough of certain nutrients. It can result from an imbalanced diet or certain health conditions or treatments. Nutritional anaemia can be caused by a lack of iron, protein, vitamin B12 (folate), and other vitamins and minerals that are needed for the formation of haemoglobin. Iron deficiency anaemia is the most common nutritional disorder.
Erythrocytosis, also known as polycythaemia, means having a high concentration of red blood cells in your blood. This makes the blood thicker and less able to travel through blood vessels and organs. Many of the symptoms of erythrocytosis are caused by this sluggish flow of blood.
In hemochromatosis (iron-overload), the role of hepcidin is affected, causing the body to absorb more iron than it needs. This excess iron is stored in major organs, especially the liver. Over a period of years, the stored iron can cause severe damage that may lead to organ failure.
What are the symptoms of a red blood cell disorder?
Symptoms of RBC disorders vary depending on their type, severity, and how they affect the red blood cells. However, as these disorders affect the functioning of RBCs, some symptoms may overlap. Symptoms that may occur with various RBC disorders include:
- Pale lips, skin and hands
- Weakness or lack of energy
- Shortness of breath
- Feeling faint when standing up too quickly
- Rapid heartbeat
- Trouble focusing
- Tingling or numbness in the hands or feet
- Jaundice or yellowing of the skin or eyes
What causes an RBC disorder?
Most RBC disorders are caused by abnormalities or mutations in the blood. In addition to genetically inherited conditions, medications, diet, lifestyle and some medical conditions can also be responsible for RBC disorders.
How are red blood cell disorders diagnosed?
RBC disorders can be suspected based on medical history and a physical exam. RBC disorders are confirmed by analysing your blood (blood tests).