Blood disorders: Types, symptoms, and causes (original) (raw)

Blood disorders are conditions that impact the blood’s ability to function correctly. Symptoms depend on the type of blood disorder. However, some common symptoms include unexplained fatigue and weight loss.

Most blood disorders decrease the number of cells, proteins, platelets, or nutrients in the blood, or interfere with their function. A majority of blood disorders are caused by mutations in parts of specific genes and can be passed down in families.

Some medical conditions, medications, and lifestyle factors can also cause blood disorders to develop.

A blood disorder is any condition that impacts one or more parts of the blood, usually interfering with its ability to work correctly.

Many blood disorders take their name from the component of the blood they impact.

The following categories describe blood disorders that cause a decrease in blood components or affect their function:

• anemia – if the disorder involves red blood cells
• leukopenia – if the disorder affects white blood cells
• thrombocytopenia – if the disorder concerns platelets

Categories of blood disorders that increase blood components are:

• erythrocytosis – if the disorder involves red blood cells
• leukocytosis – if the disorder affects white blood cells
• thrombocythemia or thrombocytosis – if the disorder concerns platelets

White blood cells help the body to fight infection. They begin life in the bone marrow and develop into different types of cells, each having a different immune purpose.

The major types are:

• neutrophils, which destroy bacteria and viruses
• lymphocytes, which kill viruses and regulate the immune system
• monocytes or macrophages, which eat dead or deactivated bacteria, viruses, and fungus
• basophils and eosinophils, which help the body respond to allergic reactions and help destroy parasites

Some white blood cell disorders impact all the different types of white blood cells in the blood, while other disorders only involve one or two specific types. Of the five types of white blood cells, neutrophils and lymphocytes get impacted the most.

Most white blood cell disorders are either a type of cancer or proliferative disorders.

Proliferative disorders involve a rapid increase in the number of white blood cells that are circulating in the blood. This mostly occurs because of an infection, although, occasionally, bone marrow cancers may be responsible.

Leukopenia, however, is due to a reduction in the amount of circulating white blood cells. Leukopenia usually occurs because of:

• illness
• infection
• toxin exposure
• certain medications, such as corticosteroids or chemotherapy medications
• genetic mutations

There are three major types of blood cancer that impact white blood cells, and they include the following:

Lymphoma

Lymphoma is a type of cancer that occurs when lymphocytes change and multiply rapidly. There are two major types of lymphoma: Hodgkin’s and non-Hodgkin lymphoma.

According to the American Cancer Society, Non-Hodgkin lymphoma is one of the more common types of cancer in the United States, accounting for 4 percent of all cancers. An estimated 74,680 diagnoses will take place in the U.S. in 2018. 70 percent of people diagnosed with non-Hodgkin’s lymphoma live at least 5 years after being diagnosed.

Hodgkin’s lymphoma is far rarer than non-Hodgkin’s lymphoma. Again, according to the American Cancer Society, around 8,500 people in the U.S. had the condition in 2018. Of those people diagnosed with Hodgkin’s lymphoma, 86 percent will live at least 5 years.

Leukemias

Leukemias involve the build-up of abnormal white blood cells in the bone marrow, which interferes with its ability to produce red blood cells and platelets. Leukemias can be acute and develop quickly, or chronic and develop more gradually over time.

The Leukemia & Lymphoma Society estimate that 60,300 people will receive a leukemia diagnosis in 2018. Between 2007 and 2017, an estimated 63.7 percent of Americans diagnosed with leukemia lived for at least 5 years after being diagnosed.

Myelomas

Myelomas involve the build-up of plasma cells in the bone marrow, which interferes with the development and function of other blood cells. The most common type of myeloma is multiple myeloma, where abnormal plasma cells build-up or form a tumor in numerous locations in the bone or marrow.

From 2008-2014, around 50.7 percent of people with myeloma lived for at least 5 years after being diagnosed, according to the National Cancer Institute. Overall, myelomas are quite rare. In 2018, myelomas represented only 1.8 percent of all newly-diagnosed cancer cases.

Treatment and diagnosis

A doctor usually diagnoses leukemias, lymphomas, and myelomas using:

• a medical exam and a complete medical history
• blood tests
• urine tests
• bone marrow aspiration and biopsy
• lumbar puncture (spinal tap), where doctors collect spinal fluid for examination
• imaging tests, such as X-ray, CT, or PET scans, MRI, and ultrasound

Blood cell cancers that do not yet cause symptoms may not require treatment aside from monitoring. Doctors usually treat people with aggressive or active blood cancers using some mix of:

• chemotherapy
• radiation therapy
• surgery
• targeted drug therapy, which are medications that help increase the effectiveness of chemotherapy drugs or destroy elements of the cancer cells that chemotherapy drugs do not
• stem cell transplants, which involve infusions containing bone marrow cells that are capable of forming blood cells to replenish destroyed cells

Anemias, where there are not enough red blood cells or the cells do not work correctly, are among the most common blood disorders. According to the American Society of Hematology, anemia affects more than 3 million Americans.

The most common types are:

• iron-deficiency anemias — when the body does not have enough iron or cannot properly absorb it
• pregnancy anemia — when there is more of a demand for red blood cells than normal
• vitamin-deficiency anemias — usually caused by low dietary intake of vitamin B-12 and folate
• non-inherited hemolytic anemias — where red blood cells are broken and destroyed in the bloodstream abnormally, either by injury, illness, or medications
• inherited hemolytic anemias — where red blood cells are broken down or destroyed more quickly than the body can replace them
• aplastic anemias — when the bone marrow stop producing enough blood cells

Treatment and diagnosis

If the cause of anemia is not apparent, such as injury or infection, or to assess anemia, a doctor will:

• do a physical exam
• review individual and family medical history
• carry out blood tests, such as complete blood counts, reticulocyte count, and peripheral blood smear
• do bone marrow aspiration and biopsy

Treatment depends on the cause but commonly includes:

• blood transfusions
• dietary changes
• surgery
• medications that stimulate the production of bone marrow and new red blood cells

Common platelet disorders include:

Hemophilia

Hemophilia is a genetic condition caused by a lack of or defective clotting factors in a person’s blood. People with hemophilia bleed longer or more excessively, both externally and internally than people without the condition.

Hemophilia is often passed down from parents to their children, but the National Hemophilia Foundation estimate that approximately one-third of cases develop spontaneously. Hemophilia is one of the better-known blood conditions, but it is still quite rare, developing in an estimated 1 in 5,000 live births.

Von Willebrand disease

This disease occurs when the body lacks the von Willebrand factor (VWF), a substance that allows platelets to stick together and form clots. Most cases of von Willebrand are relatively mild, and people may only require treatment if they are injured or undergo surgery.

While many platelet disorders involve a reduction in the number of platelets present in the blood or their function, several conditions can cause an excess of platelets.

Treatment and diagnosis

To diagnose and assess platelet conditions, most doctors will carry out:

• a physical exam
• a review of individual and family medical history
• blood tests

Treating blood clotting disorders typically involves replacement therapy, where the doctor gives a person infusions containing the specific clotting factors they are lacking.

Additional therapies include:

• desmopressin — a synthetic hormone that promotes the release of von Willebrand factor and factor VIII
• antifibrinolytic medications — that help prevent blood clots from breaking down
• birth control medications — to reduce heavy menstrual cycles

Additional treatment options include:

• blood transfusions
• corticosteroids to slow platelet destruction
• immunoglobulins to block the immune system
• surgery to remove the spleen in severe cases

Symptoms depend on what part of the blood or organs is affected, as well as the severity and extent of the condition.

However, the majority of people with significant blood disorders tend to experience a general feeling of being unwell for no apparent reason.

Signs of white blood cell disorders include:

• frequent infections
• wounds that do not heal or are slow to heal
• unexplained exhaustion
• unexplained weight loss

Signs of red blood cell disorders include:

• unexplained exhaustion
• shortness of breath
• dizziness or light-headedness
• rapid heartbeat
• muscle weakness
• difficulty concentrating and remembering
• paleness

Signs of platelet and clotting disorders include:

• difficulty forming blood clots at wounds or controlling bleeding
• injuries that are slow to heal or keep re-opening
• unexplainable bruising or skin that easily bruises
• unexplainable bleeding from the nose, gums, gastrointestinal system, or urogenital system

Many blood disorders can affect different components of the blood, including the white blood cells, red blood cells, and plasma.

Symptoms vary according to the type of blood disorder a person has, but most include general feelings of being unwell with no apparent cause, unexplained exhaustion, and unexplained weight loss.

Treatments vary depending on the type and severity of the condition but will often include chemotherapy or radiation therapy.