Common & Rare Hematological Disorders

Instructor: Sarah Friedl

Sarah has two Master's, one in Zoology and one in GIS, a Bachelor's in Biology, and has taught college level Physical Science and Biology.

Your blood is an important component of your body, so when there is a problem with your blood it can cause serious issues. In this lesson, we'll look at some of the more common blood disorders as well as some that are less likely to occur.

What is a Blood Disorder?

Your blood is a very important component of your body. Blood transports gases like oxygen and carbon dioxide, nutrients, waste products, and hormones throughout your body. Blood helps regulate your body temperature, your body's pH, and even its balance of water. Your blood cells help protect you from infection and inflammation and also form clots so that you don't lose too much blood at once.

So you can probably imagine that if you have a blood or hematological disorder, then your whole body is at risk for problems. But what is that word hematological and what does it have to do with blood disorders? Have you heard of the protein hemoglobin? Heme is a part of this protein, and is the iron-containing molecule within blood that carries oxygen from your lungs to other tissues in your body. It's what makes your blood red and gives it that metallic taste. It's also where hematology, or the study of blood in health and disease gets its name. So it's only fitting that hematological disorders are disorders of the blood.

Blood is made of different components, such as red blood cells (left) and white blood cells (right)
red and white blood cell

While, from our vantage point, blood looks like a simple red fluid, it actually has several different components. Blood is made up of:

  • Red blood cells, which is where we find heme
  • White blood cells, which fight off infection
  • Platelets, which help your blood to clot
  • Plasma, which is the actual liquid part of blood that carries all of the things mentioned before such as nutrients, hormones, and waste products

A problem can arise with any one of these components and lead to a hematological disorder in the body.

Common Hematological Disorders

With so many different components that have so many functions in the body, there are, of course, many different types of hematological disorders. Let's look first at some of the more common ones, starting with red blood cell disorders.

Red Blood Cell Disorders

Red blood cells carry fresh oxygen around your body. Some common red blood cell disorders include:

  • Anemia: too few red blood cells are produced by the body
  • Sickle cell anemia: red blood cells are sickle or 'C' shaped, which blocks blood flow to organs and limbs
  • Thalassemia: a hereditary disorder where the body makes too few red blood cells and too little hemoglobin

Sickle cell anemia causes red blood cells to be sickle or C shaped
sickle cell red blood cell

White Blood Cell Disorders

White blood cells help protect you from infection and disease, and are therefore important to your health. Some common white blood cell disorders include:

  • Leukemia: a cancer of the bone marrow and blood, creating an overproduction of white blood cells
  • Leukopenia: low white blood cell count, sometimes caused by other illnesses
  • Lymphoma: a cancer in lymphocytes, which are white blood cells in the immune system
  • Myeloma: a form of cancer that affects plasma cells, which are a type of white blood cell

Blood disorders involving an over-production of white blood cells can lead to various cancers
cancer cells

Platelet Disorders

Platelets are important because they stop you from bleeding. Some common platelet disorders include:

  • Blood clots: can prevent blood flow when formed inside vessels or are not dissolved by the body
  • Hemophilia: a deficiency in one of two blood clotting factors, leading to excessive bleeding
  • Immune thrombocytopenic purpura: a decreased number of platelets, which causes bleeding and easy bruising
  • Thrombocytosis: too many platelets are produced, leading to excessive clotting and/or bleeding

Blood disorders involving platelets can affect your ability to clot and cause excessive bruising
platelet blood disorder

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